E28.01 - Calibration of Mechanical Testing Machines and Apparatus

SIGNIFICANCE AND USE
4.1 Material testing requires repeatable and predictable testing machine speed. The speed measuring devices integral to the testing machines may be used for measurement of crosshead speed over a defined range of operation. The accuracy of the speed value shall be traceable to a National or International Standards Laboratory. Practices E2658 provides procedures to verify testing machines, in order that the indicated speed values may be traceable. A key element to having traceability is that the devices used in the verification produce known speed characteristics, and have been calibrated in accordance with adequate calibration standards.  
4.2 Verification of testing machine speed at a minimum consists of either or both of the following options:  
4.2.1 Verifying the capability of the testing machine to move the crosshead at the speed selected.  
4.2.2 Verifying the capability of the testing machine to adequately indicate the speed of the crosshead.  
4.3 Where applicable, determine the testing machine's ramp-to-speed condition. This condition can be significant especially when verifying fast speeds or testing conditions with very short testing durations.  
4.4 This procedure will establish the relationship between the actual crosshead speed and the testing machine indicated speed and or selected setting. It is this relationship that will allow confidence in the reported displacement over time data acquired by the testing machine during use.
Note 1: Many material tests never reach the desired test speed. Unless the actual data from the material test is examined, it is often impossible to know if the test speed has been reached or is repeatable from test to test.
SCOPE
1.1 These practices cover procedures and requirements for the calibration and verification of testing machine speed by means of standard calibration devices. This practice is not intended to be complete purchase specifications for testing machines.  
1.2 These practices apply to the verification of the speed application and measuring systems associated with the testing machine, such as a scale, dial, marked or unmarked recorder chart, digital display, setting, etc. In all cases the buyer/owner/user must designate the speed-measuring system(s) to be verified.  
1.3 These practices give guidance, recommendations, and examples, specific to electro-mechanical testing machines. The practice may also be used to verify actuator speed for hydraulic testing machines.  
1.4 This standard cannot be used to verify cycle counting or frequency related to cyclic fatigue testing applications.  
1.5 Since conversion factors are not required in this practice, either SI units (mm/min), or English [in/min], can be used as the standard.  
1.6 Speed measurement values and or settings on displays/printouts of testing machine data systems-be they instantaneous, delayed, stored, or retransmitted-which are within the Classification criteria listed in Table 1, comply with Practices E2658.  
1.7 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety, health, and environmental practices and determine the applicability of regulatory limitations prior to use.  
1.8 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.

SIGNIFICANCE AND USE
4.1 The use of this guide is voluntary and is intended for use as a procedures guide for selection and application of specific types of strain gages for high-temperature installations. No attempt is made to restrict the type of strain gage types or concepts to be chosen by the user. The provisions of this guide may be invoked in specifications and procedures by specifying those that shall be considered mandatory for the purpose of the specific application. When so invoked, the user shall include in the work statement a notation that provisions of this guide shown as recommendation shall be considered mandatory for the purposes of the specification or procedure concerned, and shall include a statement of any exceptions to or modifications of the affected provisions of this guide.
SCOPE
1.1 This guide covers the selection and application of strain gages for the measurement of static strain up to and including the temperature range from 425 °C to 650 °C (800 °F to 1200 °F). This guide reflects some state-of-the-art techniques in high-temperature strain measurement.  
1.2 This guide assumes that the user is familiar with the use of bonded strain gages and associated signal conditioning circuits and instrumentation as discussed in  (1)  and (2).2 The strain gage systems described are those that have proven effective in the temperature range of interest and were available at the time of issue of this guide. It is not the intent of this guide to limit the user to one of the strain gage types described nor is it the intent to specify the type of strain gage system to be used for a specific application. However, in using any strain gage system including those described, the proposer shall be able to demonstrate the capability of the proposed strain gage system to meet the selection criteria provided in Section 5 and the needs of the specific application.  
1.3 The devices and techniques described in this guide can sometimes be applicable at temperatures above and below the range noted, and for making dynamic strain measurements at high temperatures with proper precautions. The strain gage manufacturer should be consulted for recommendations and details of such applications.  
1.4 The references are a part of this guide to the extent specified in the text.  
1.5 The values stated in metric (SI) units are to be regarded as the standard. The values given in parentheses are for informational purposes only.  
1.6 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety, health, and environmental practices and determine the applicability of regulatory limitations prior to use.  
1.7 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.

ABSTRACT
This practice covers procedures for the verification and classification of extensometer systems, but it is not intended to be a complete purchase specification. The practice is applicable only to instruments that indicate or record values that are proportional to changes in length corresponding to either tensile or compressive strain. Extensometer systems are classified on the basis of the magnitude of their errors. The apparatus for verifying extensometer systems shall provide a means for applying controlled displacements to a simulated specimen and for measuring these displacements accurately. Extensometer systems shall be classified in accordance with the requirements as to maximum error of strain indicated: Class A; Class B-1; Class B-2; Class C; Class D; and Class E. Extensometer systems shall be categorized in three types according to gage length: Type 1; Type 2; and Type 3. A verification procedure for extensometer systems shall be done in accordance with the specified requirements.
SCOPE
1.1 This practice covers procedures for the verification and classification of extensometer systems, but it is not intended to be a complete purchase specification. The practice is applicable only to instruments that indicate or record values that are proportional to changes in length corresponding to either tensile or compressive strain. Extensometer systems are classified on the basis of the magnitude of their errors.  
1.2 Because strain is a dimensionless quantity, this document can be used for extensometers based on either SI or US customary units of displacement.  
Note 1: Bonded resistance strain gauges directly bonded to a specimen cannot be calibrated or verified with the apparatus described in this practice for the verification of extensometers having definite gauge points. (See procedures as described in Test Methods E251.)  
1.3 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety, health, and environmental practices and determine the applicability of regulatory limitations prior to use.  
1.4 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.

SIGNIFICANCE AND USE
4.1 Testing machines that apply and indicate torque are in general use in many industries. Practice E2624 has been written to provide a practice for the torque calibration and verification of these testing machines. A necessary element in Practice E2624 is the use of elastic torque measurement standards whose torque characteristics are known to be metrologically traceable to the International System of Units (SI). Practice E2428 describes how these elastic torque measurement standards are to be calibrated. The procedures are useful to users of testing machines, manufacturers and providers of elastic torque measurement standards, calibration laboratories that provide calibration services and documents of metrological traceability, service organizations using elastic torque measurement standards to calibrate and verify testing machines, and testing laboratories performing general structural test measurements.
SCOPE
1.1 The purpose of this practice is to specify the procedure for the calibration and verification of elastic torque measurement standards.  
1.2 Units—The values stated in SI units are to be regarded as standard. The values given in parentheses after SI units are provided for information only and are not considered standard.  
1.3 This practice is intended for the calibration of static elastic torque measurement standards. The practice is not applicable for dynamic or high-speed torque calibrations or measurements, nor can the results of calibrations performed in accordance with this practice be assumed valid for dynamic or high-speed torque measurements.  
1.4 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety, health, and environmental practices and determine the applicability of regulatory limitations prior to use.  
1.5 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.

SIGNIFICANCE AND USE
5.1 Testing machines that apply and indicate force are used in many industries, in many ways. They might be used in a research laboratory to measure material properties, or in a production line to qualify a product for shipment. No matter what the end use of the testing machine may be, it is necessary for users to know that the amount of force applied and indicated is traceable to the International System of Units (SI) through a National Metrology Institute (NMI). The procedures in Practices E4 may be used to calibrate these testing machines so that the measured forces are traceable to the SI. A key element of traceability to the SI is that the force measurement standards used in the calibration have known force characteristics, and have been calibrated in accordance with Practice E74.  
5.2 The procedures in Practices E4 may be used by those using, manufacturing, and providing calibration service for testing machines and related instrumentation.
SCOPE
1.1 These practices cover procedures for the force calibration and verification, by means of force measurement standards, of tension or compression, or both, static or quasi-static testing machines (which may, or may not, have force-indicators). These practices are not intended to be complete purchase specifications for testing machines.  
1.2 Testing machines may be verified by one of the three following methods or combination thereof. Each of the methods require a specific measurement uncertainty, displaying metrological traceability to The International System of Units (SI).  
1.2.1 Use of standard weights,  
1.2.2 Use of equal-arm balances and standard weights, or  
1.2.3 Use of elastic force measurement standards.  
1.3 The procedures of 1.2.1–1.2.3 apply to the calibration and verification of the force-measuring systems associated with the testing machine, including the force indicators such as a scale, dial, marked or unmarked recorder chart, digital display, etc. In all cases the buyer/owner/user must designate the force-measuring system(s) to be verified and included in the certificate and report of calibration and verification.  
1.4 Units—The values stated in either SI units or inch-pound units are to be regarded separately as standard. The values stated in each system are not necessarily exact equivalents; therefore, to ensure conformance with the standard, each system shall be used independently of the other, and values from the two systems shall not be combined.  
1.4.1 Other non-SI force units may be used with this standard such as the kilogram-force (kgf) which is often used with hardness testing machines  
1.5 Forces indicated on displays/printouts of testing machine data systems—be they instantaneous, delayed, stored, or retransmitted—which are verified with provisions of 1.2.1, 1.2.2, or 1.2.3, and are within the specifications stated in Section 15, comply with Practices E4.  
1.6 The requirements of these practices limit the major components of measurement uncertainty when calibrating testing machines. These Standard Practices do not require the allowable force measurement error to be reduced by the amount of the measurement uncertainty encountered during a calibration. As a result, a testing machine verified using these practices may produce a deviation from the true force greater than ±1.0 % when the force measurement error is combined with the measurement uncertainty.  
1.7 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety, health, and environmental practices and determine the applicability of regulatory limitations prior to use.  
1.8 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued...

SIGNIFICANCE AND USE
4.1 Strain gages are the most widely used devices for measuring strains and for evaluating stresses in structures. In many applications there are often cyclic loads that can cause strain gage failure. Performance characteristics of strain gages are affected by both the materials from which they are made and their geometric design.  
4.2 The determination of most strain gage performance characteristics requires mechanical testing that is destructive. Since strain gages tested for fatigue life cannot be used again, it is necessary to treat data statistically. In general, longer and wider strain gages with lower resistances will have greater fatigue life. Optional additions to strain gages (integral lead wires are an example) will often reduce fatigue life.  
4.3 To be used, strain gages must be bonded to a structure. Good results, particularly in a fatigue environment, depend heavily on the materials used to clean the bonding surface, to bond the strain gage, and to provide a protective coating. Skill of the installer is another major factor in success. Finally, instrumentation systems shall be carefully selected and calibrated to ensure that they do not unduly degrade the performance of the strain gages.  
4.4 Fatigue failure of a strain gage often does not involve visible cracking or fracture of the strain gage, but merely sufficient zero shift to compromise the accuracy of the strain gage output for static strain components.
SCOPE
1.1 This test method covers a uniform procedure for the determination of strain gage fatigue life at ambient temperature. A suggested testing equipment design is included.  
1.2 This test method does not apply to force transducers or extensometers that use metallic bonded resistance strain gages as sensing elements.  
1.3 Strain gages are part of a complex system that includes structure, adhesive, strain gage, lead wires, instrumentation, and (often) environmental protection. As a result, many things affect the performance of strain gages, including user technique. A further complication is that strain gages, once installed, normally cannot be reinstalled in another location. Therefore, it is not possible to calibrate individual strain gages; performance characteristics are normally presented on a statistical basis.  
1.4 This test method encompasses only fully reversed stain cycles.  
1.5 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety, health, and environmental practices and determine the applicability of regulatory limitations prior to use.  
1.6 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.

ABSTRACT
This practice defines a reference axis for each of the two principal types of rosette configurations and the equations used for three-element strain gage rosette data analysis. The primary uses of this analysis procedure are to determine the directions and magnitudes of the principal surface strains, and to determine residual stresses. This is important for consistency in reporting results and for avoiding ambiguity in data analysis, especially when computers are used. There are several possible sets of equations, but the set presented herein is perhaps the most common.
SCOPE
1.1 The two primary uses of three-element strain gage rosettes are (a) to determine the directions and magnitudes of the principal surface strains and (b) to determine residual stresses. Residual stresses are treated in a separate ASTM standard, Test Method E837. This practice defines a reference axis for each of the two principal types of rosette configurations used and presents equations for data analysis. This is important for consistency in reporting results and for avoiding ambiguity in data analysis—especially when computers are used. There are several possible sets of equations, but the set presented here is perhaps the most common.  
1.2 The equations in 4.2 and 4.3 of this practice are derived from infinitesimal (linear) strain theory. They are very accurate for the low strain levels normally encountered in the stress analysis of typical metal test objects. They become detectably inaccurate for strain levels greater than about 1 %. Rosette data reduction for larger strains is beyond the scope of this practice.  
1.3 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.

SIGNIFICANCE AND USE
4.1 Methods and procedures used in installing bonded resistance strain gages can have significant effects upon the performance of those sensors. Optimum and reproducible detection of surface deformation requires appropriate and consistent strain gage and bonding technique selection, surface preparation, procedures for gage installation and adhesive use, lead wire connection, validation of operation, and protective coating application.
SCOPE
1.1 This guide provides guidelines for installing bonded resistance strain gages. It is not intended to be used for bulk or diffused semiconductor gages. This guide pertains only to adhesively bonded strain gages.  
1.2 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard.  
1.3 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety, health, and environmental practices and determine the applicability of regulatory limitations prior to use.  
1.4 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.

SIGNIFICANCE AND USE
4.1 Strain gages are the most widely used devices for the determination of materials, properties and for analyzing stresses in structures. However, performance characteristics of strain gages are affected by both the materials from which they are made and their geometric design. These test methods detail the minimum information that must accompany strain gages if they are to be used with acceptable accuracy of measurement.  
4.2 Most performance characteristics of strain gages require mechanical testing that is destructive. Since test strain gages cannot be used again, it is necessary to treat data statistically and then apply values to the remaining population from the same lot or batch. Failure to acknowledge the resulting uncertainties can have serious repercussions. Resistance measurement is non-destructive and can be made for each strain gage.  
4.3 Properly designed and manufactured strain gages, whose performance characteristics have been accurately determined and with appropriate uncertainties applied, represent powerful measurement tools. They can determine small dimensional changes in structures with excellent accuracy, far beyond that of other known devices. It is important to recognize, however, that individual strain gages cannot be calibrated. If calibration and traceability to a standard are required, strain gages should not be employed.  
4.4 To be used, strain gages must be bonded to a structure. Good results depend heavily on the materials used to clean the bonding surface, to bond the strain gage, and to provide a protective coating. Skill of the installer is another major factor in success. Finally, instrumentation systems must be carefully designed to assure that they do not unduly degrade the performance of the strain gages. In many cases, it is impossible to achieve this goal. If so, allowance must be made when considering accuracy of data. Test conditions can, in some instances, be so severe that error signals from strain gage systems far ...
SCOPE
1.1 The purpose of these test methods are to provide uniform test methods for the determination of strain gage performance characteristics. Suggested testing equipment designs are included.  
1.2 Test Methods E251 describes methods and procedures for determining five strain gage performance characteristics:    
Section  
Part I—General Requirements  
7  
Part II—Resistance at a Reference Temperature  
8  
Part III—Gage Factor at a Reference Temperature  
9  
Part IV—Temperature Coefficient of Gage Factor  
10  
Part V—Transverse Sensitivity  
11  
Part VI—Thermal Output  
12  
1.3 Strain gages are very sensitive devices with essentially infinite resolution. Their response to strain, however, is low and great care must be exercised in their use. The performance characteristics identified by these test methods must be known to an acceptable accuracy to obtain meaningful results in field applications.  
1.3.1 Strain gage resistance is used to balance instrumentation circuits and to provide a reference value for measurements since all data are related to a change in the strain gage resistance from a known reference value.  
1.3.2 Gage factor is the transfer function of a strain gage. It relates resistance change in the strain gage and strain to which it is subjected. Accuracy of strain gage data can be no better than the accuracy of the gage factor.  
1.3.3 Changes in gage factor as temperature varies also affect accuracy although to a much lesser degree since variations are usually small.  
1.3.4 Transverse sensitivity is a measure of the strain gage's response to strains perpendicular to its measurement axis. Although transverse sensitivity is usually much less than 10 % of the gage factor, large errors can occur if the value is not known with reasonable precision.  
1.3.5 Thermal output is the response of a strain gage to temperature changes. Thermal output is an additive (not multiplica...

SIGNIFICANCE AND USE
4.1 Testing machines that apply and measure displacement are used in many industries. They may be used in research laboratories to determine material properties, and in production lines to qualify products for shipment. The displacement measuring devices integral to the testing machines may be used for measurement of crosshead or actuator displacement over a defined range of operation. The accuracy of the displacement value shall be traceable to the National Institute of Standards and Technology (NIST) or another recognized National Laboratory. Practices E2309 provides a procedure to verify these machines and systems, in order that the measured displacement values may be traceable. A key element to having traceability is that the devices used in the verification produce known displacement characteristics, and have been calibrated in accordance with adequate calibration standards.
SCOPE
1.1 These practices cover procedures and requirements for the calibration and verification of displacement measuring systems by means of standard calibration devices for static and quasi-static testing machines. This practice is not intended to be complete purchase specifications for testing machines or displacement measuring systems. Displacement measuring systems are not intended to be used for the determination of strain. See Practice E83.  
1.2 These procedures apply to the verification of the displacement measuring systems associated with the testing machine, such as a scale, dial, marked or unmarked recorder chart, digital display, etc. In all cases the buyer/owner/user must designate the displacement-measuring system(s) to be verified.  
1.3 The values stated in either SI units or inch-pound units are to be regarded separately as standard. The values stated in each system may not be exact equivalents; therefore, each system shall be used independently of the other. Combining values from the two systems may result in non-conformance with the standard.  
1.4 Displacement values indicated on displays/printouts of testing machine data systems—be they instantaneous, delayed, stored, or retransmitted—which are within the Classification criteria listed in Table 1, comply with Practices E2309/E2309M.  
1.5 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety, health, and environmental practices and determine the applicability of regulatory limitations prior to use.  
1.6 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.

SIGNIFICANCE AND USE
4.1 It has been shown that bending stresses that inadvertently occur due to misalignment between the applied force and the specimen axes during the application of tensile and compressive forces can affect the test results. In recognition of this effect, some test methods include a statement limiting the misalignment that is permitted. The purpose of this practice is to provide a reference for test methods and practices that require the application of tensile or compressive forces under conditions where alignment is important. The objective is to implement the use of common terminology and methods for verification of alignment of testing machines, associated components and test specimens.  
4.2 Alignment verification intervals when required are specified in the methods or practices that require the alignment verification. Certain types of testing can provide an indication of the current alignment condition of a testing frame with each specimen tested. If a test method requires alignment verification, the frequency of the alignment verification should capture all the considerations that is, time interval, changes to the testing frame and when applicable, current indicators of the alignment condition through test results.  
4.3 Whether or not to improve axiality should be a matter of negotiation between the interested parties.
SCOPE
1.1 Included in this practice are methods covering the determination of the amount of bending that occurs during the application of tensile and compressive forces to notched and unnotched test specimens during routine testing in the elastic range. These methods are particularly applicable to the force levels normally used for tension testing, compression testing, creep testing, and uniaxial fatigue testing. The principal objective of this practice is to assess the amount of bending exerted upon a test specimen by the ordinary components assembled into a materials testing machine, during routine tests.  
1.2 This practice is valid for metallic and nonmetallic testing.  
1.3 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.

SIGNIFICANCE AND USE
4.1 Testing machines that apply and indicate force are in general use in many industries. Practices E4 has been written to provide a practice for the force verification of these machines. A necessary element in Practices E4 is the use of force-measuring instruments whose force characteristics are known to be traceable to the SI. Practices E74 describes how these force-measuring instruments are to be calibrated. The procedures are useful to users of testing machines, manufacturers and providers of force-measuring instruments, calibration laboratories that provide the calibration of the instruments and the documents of traceability, service organizations that use the force-measuring instruments to verify testing machines, and testing laboratories performing general structural test measurements.
SCOPE
1.1 The purpose of these practices is to specify procedures for the calibration of force-measuring instruments. Procedures are included for the following types of instruments:  
1.1.1 Elastic force-measuring instruments, and  
1.1.2 Force-multiplying systems, such as balances and small platform scales.  
Note 1: Verification by deadweight loading is also an acceptable method of verifying the force indication of a testing machine. Tolerances for weights for this purpose are given in Practices E4; methods for calibration of the weights are given in NIST Technical Note 577(1)2, Methods of Calibrating Weights for Piston Gages.  
1.2 The values stated in SI units are to be regarded as the standard. Other metric and inch-pound values are regarded as equivalent when required.  
1.3 These practices are intended for the calibration of static force measuring instruments. It is not applicable for dynamic or high speed force calibrations, nor can the results of calibrations performed in accordance with these practices be assumed valid for dynamic or high speed force measurements.  
1.4 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety, health, and environmental practices and determine the applicability of regulatory limitations prior to use.  
1.5 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.

SIGNIFICANCE AND USE
4.1 Testing machines that apply and indicate torque are used in many industries, in many ways. They may be used in a research laboratory to measure material properties, and in a production line to qualify a product for shipment. No matter what the end use of the machine may be, it is necessary for users to know the amount of torque that is applied, and that the accuracy of the torque value is traceable to the SI. This standard provides a procedure to verify these machines and devices, in order that the indicated torque values may be traceable. A key element to having metrological traceability is that the devices used in the calibration produce known torque characteristics, and have been calibrated in accordance with Practice E2428.  
4.2 This standard may be used by those using, those manufacturing, and those providing calibration service for torque capable testing machines or devices and related instrumentation.
SCOPE
1.1 This practice covers procedures and requirements for the calibration of torque for static and quasi-static torque capable testing machines. These may, or may not, have torque indicating systems and include those devices used for the calibration of hand torque tools. Testing machines may be calibrated by one of the three following methods or combination thereof:  
1.1.1 Use of standard weights and lever arms.  
1.1.2 Use of elastic torque measuring devices.  
1.1.3 Use of elastic force measuring devices and lever arms.  
1.1.4 Any of the methods require a specific uncertainty of measurement, displaying metrological traceability to The International System of Units (SI).
Note 1: – for further definition of the term metrological traceability, refer to the latest revision of JCGM 200: International vocabulary of metrology — Basic and general concepts and associated terms (VIM).  
1.2 The procedures of 1.1.1, 1.1.2, and 1.1.3 apply to the calibration of the torque-indicating systems associated with the testing machine, such as a scale, dial, marked or unmarked recorder chart, digital display, etc. In all cases the buyer/owner/user must designate the torque-indicating system(s) to be calibrated and included in the report.  
1.3 Since conversion factors are not required in this practice, either english units, metric units, or SI units can be used as the standard.  
1.4 Torque values indicated on displays/printouts of testing machine data systems—be they instantaneous, delayed, stored, or retransmitted—which are calibrated with provisions of 1.1.1, 1.1.2 or 1.1.3 or a combination thereof, and are within the ±1 % of reading accuracy requirement, comply with this practice.  
1.5 The following applies to all specified limits in this standard: For purposes of determining conformance with these specifications, an observed value or a calculated value shall be rounded “to the nearest unit” in the last right-hand digit used in expressing the specification limit, in accordance with the rounding method of Practice E29, for Using Significant Digits in Test Data to Determine Conformance with Specifications.  
1.6 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety, health, and environmental practices and determine the applicability of regulatory limitations prior to use.  
1.7 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.

SIGNIFICANCE AND USE
4.1 The use of this guide is voluntary and is intended for use as a procedures guide for selection and application of specific types of strain gages for high-temperature installations. No attempt is made to restrict the type of strain gage types or concepts to be chosen by the user. The provisions of this guide may be invoked in specifications and procedures by specifying those that shall be considered mandatory for the purpose of the specific application. When so invoked, the user shall include in the work statement a notation that provisions of this guide shown as recommendation shall be considered mandatory for the purposes of the specification or procedure concerned, and shall include a statement of any exceptions to or modifications of the affected provisions of this guide.
SCOPE
1.1 This guide covers the selection and application of strain gages for the measurement of static strain up to and including the temperature range from 425 °C to 650 °C (800 °F to 1200 °F). This guide reflects some state-of-the-art techniques in high-temperature strain measurement.  
1.2 This guide assumes that the user is familiar with the use of bonded strain gages and associated signal conditioning circuits and instrumentation as discussed in  (1)  and (2).2 The strain gage systems described are those that have proven effective in the temperature range of interest and were available at the time of issue of this guide. It is not the intent of this guide to limit the user to one of the strain gage types described nor is it the intent to specify the type of strain gage system to be used for a specific application. However, in using any strain gage system including those described, the proposer shall be able to demonstrate the capability of the proposed strain gage system to meet the selection criteria provided in Section 5 and the needs of the specific application.  
1.3 The devices and techniques described in this guide can sometimes be applicable at temperatures above and below the range noted, and for making dynamic strain measurements at high temperatures with proper precautions. The strain gage manufacturer should be consulted for recommendations and details of such applications.  
1.4 The references are a part of this guide to the extent specified in the text.  
1.5 The values stated in metric (SI) units are to be regarded as the standard. The values given in parentheses are for informational purposes only.  
1.6 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety, health, and environmental practices and determine the applicability of regulatory limitations prior to use.  
1.7 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.

SIGNIFICANCE AND USE
4.1 Strain gages are the most widely used devices for the determination of materials, properties and for analyzing stresses in structures. However, performance parameters of strain gages are affected by both the materials from which they are made and their geometric design. These test methods detail the minimum information that must accompany strain gages if they are to be used with acceptable accuracy of measurement.  
4.2 Most performance parameters of strain gages require mechanical testing that is destructive. Since test gages cannot be used again, it is necessary to treat data statistically and then apply values to the remaining population from the same lot or batch. Failure to acknowledge the resulting uncertainties can have serious repercussions. Resistance measurement is non-destructive and can be made for each gage.  
4.3 Properly designed and manufactured strain gages, whose properties have been accurately determined and with appropriate uncertainties applied, represent powerful measurement tools. They can determine small dimensional changes in structures with excellent accuracy, far beyond that of other known devices. It is important to recognize, however, that individual strain gages cannot be calibrated. If calibration and traceability to a standard are required, strain gages should not be employed.  
4.4 To be used, strain gages must be bonded to a structure. Good results depend heavily on the materials used to clean the bonding surface, to bond the gage, and to provide a protective coating. Skill of the installer is another major factor in success. Finally, instrumentation systems must be carefully designed to assure that they do not unduly degrade the performance of the gages. In many cases, it is impossible to achieve this goal. If so, allowance must be made when considering accuracy of data. Test conditions can, in some instances, be so severe that error signals from strain gage systems far exceed those from the structural deformations to be mea...
SCOPE
1.1 The purpose of these test methods are to provide uniform test methods for the determination of strain gage performance characteristics. Suggested testing equipment designs are included.  
1.2 Test Methods E251 describes methods and procedures for determining five strain gage parameters:    
Section  
Part I—General Requirements  
7  
Part II—Resistance at a Reference Temperature  
8  
Part III—Gage Factor at a Reference Temperature  
9  
Part IV—Temperature Coefficient of Gage Factor  
10  
Part V—Transverse Sensitivity  
11  
Part VI—Thermal Output  
12  
1.3 Strain gages are very sensitive devices with essentially infinite resolution. Their response to strain, however, is low and great care must be exercised in their use. The performance characteristics identified by these test methods must be known to an acceptable accuracy to obtain meaningful results in field applications.  
1.3.1 Strain gage resistance is used to balance instrumentation circuits and to provide a reference value for measurements since all data are related to a change in the gage resistance from a known reference value.  
1.3.2 Gage factor is the transfer function of a strain gage. It relates resistance change in the gage and strain to which it is subjected. Accuracy of strain gage data can be no better than the precision of the gage factor.  
1.3.3 Changes in gage factor as temperature varies also affect accuracy although to a much lesser degree since variations are usually small.  
1.3.4 Transverse sensitivity is a measure of the strain gage's response to strains perpendicular to its measurement axis. Although transverse sensitivity is usually much less than 10 % of the gage factor, large errors can occur if the value is not known with reasonable precision.  
1.3.5 Thermal output is the response of a strain gage to temperature changes. Thermal output is an additive (not multiplicative) error. Therefore, it can...

SIGNIFICANCE AND USE
4.1 Testing machines that apply and indicate force are used in many industries, in many ways. They may be used in a research laboratory to measure material properties, and in a production line to qualify a product for shipment. No matter what the end use of the machine may be, it is necessary for users to know that the amount of force applied and indicated is traceable to the International System of Units (SI) through a National Metrology Institute (NMI). The procedures in Practices E4 may be used to verify these machines so that the indicated forces are traceable to the SI. A key element of traceability to the SI is that the devices used in the verification have known force characteristics, and have been calibrated in accordance with Practice E74.  
4.2 The procedures in Practices E4 may be used by those using, manufacturing, and providing calibration service for testing machines and related instrumentation.
SCOPE
1.1 These practices cover procedures for the force verification, by means of force measurement standards, of tension or compression, or both, static or quasi-static testing machines (which may, or may not, have force-indicating systems). These practices are not intended to be complete purchase specifications for testing machines.  
1.2 Testing machines may be verified by one of the three following methods or combination thereof. Each of the methods require a specific uncertainty of measurement, displaying metrological traceability to The International System of Units (SI).  
1.2.1 Use of standard weights,  
1.2.2 Use of equal-arm balances and standard weights, or  
1.2.3 Use of force-measuring instruments.  
1.3 The term ’metrological traceability’ is used as defined in the JCGM 200: International vocabulary of metrology-Basic and general concepts and associated terms (VIM).  
1.4 The procedures of 1.2.1–1.2.3 apply to the verification of the force-indicating systems associated with the testing machine, such as a scale, dial, marked or unmarked recorder chart, digital display, etc. In all cases the buyer/owner/user must designate the force-indicating system(s) to be verified and included in the report.  
1.5 Units—The values stated in either SI units or inch-pound units are to be regarded separately as standard. The values stated in each system are not necessarily exact equivalents; therefore, to ensure conformance with the standard, each system shall be used independently of the other, and values from the two systems shall not be combined.  
1.5.1 Other customary force units may be used with this standard such as the kilogram-force (kgf) which is often used with hardness testing machines  
1.6 Forces indicated on displays/printouts of testing machine data systems—be they instantaneous, delayed, stored, or retransmitted—which are verified with provisions of 1.2.1, 1.2.2, or 1.2.3, and are within the ±1 % measurement accuracy requirement, comply with Practices E4.  
1.7 The requirements of these practices limit the major components of measurement uncertainty when verifying testing machines. These Standard Practices do not require the allowable error to be reduced by the amount of the measurement uncertainty encountered during a verification. As a result, a testing machine verified using these practices may produce a deviation from the true force greater than ±1.0 % when the error is combined with the measurement uncertainty  
1.8 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety, health, and environmental practices and determine the applicability of regulatory limitations prior to use.  
1.9 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by ...

SIGNIFICANCE AND USE
4.1 Testing machines that apply and indicate force are in general use in many industries. Practices E4 has been written to provide a practice for the force verification of these machines. A necessary element in Practices E4 is the use of force-measuring instruments whose force characteristics are known to be traceable to the SI. Practices E74 describes how these force-measuring instruments are to be calibrated. The procedures are useful to users of testing machines, manufacturers and providers of force-measuring instruments, calibration laboratories that provide the calibration of the instruments and the documents of traceability, service organizations that use the force-measuring instruments to verify testing machines, and testing laboratories performing general structural test measurements.
SCOPE
1.1 The purpose of these practices is to specify procedures for the calibration of force-measuring instruments. Procedures are included for the following types of instruments:  
1.1.1 Elastic force-measuring instruments, and  
1.1.2 Force-multiplying systems, such as balances and small platform scales.  
Note 1: Verification by deadweight loading is also an acceptable method of verifying the force indication of a testing machine. Tolerances for weights for this purpose are given in Practices E4; methods for calibration of the weights are given in NIST Technical Note 577(1)2, Methods of Calibrating Weights for Piston Gages.  
1.2 The values stated in SI units are to be regarded as the standard. Other metric and inch-pound values are regarded as equivalent when required.  
1.3 These practices are intended for the calibration of static force measuring instruments. It is not applicable for dynamic or high speed force calibrations, nor can the results of calibrations performed in accordance with these practices be assumed valid for dynamic or high speed force measurements.  
1.4 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety, health, and environmental practices and determine the applicability of regulatory limitations prior to use.  
1.5 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.

ABSTRACT
This practice covers procedures for the verification and classification of extensometer systems, but it is not intended to be a complete purchase specification. The practice is applicable only to instruments that indicate or record values that are proportional to changes in length corresponding to either tensile or compressive strain. Extensometer systems are classified on the basis of the magnitude of their errors. The apparatus for verifying extensometer systems shall provide a means for applying controlled displacements to a simulated specimen and for measuring these displacements accurately. Extensometer systems shall be classified in accordance with the requirements as to maximum error of strain indicated: Class A; Class B-1; Class B-2; Class C; Class D; and Class E. Extensometer systems shall be categorized in three types according to gage length: Type 1; Type 2; and Type 3. A verification procedure for extensometer systems shall be done in accordance with the specified requirements.
SCOPE
1.1 This practice covers procedures for the verification and classification of extensometer systems, but it is not intended to be a complete purchase specification. The practice is applicable only to instruments that indicate or record values that are proportional to changes in length corresponding to either tensile or compressive strain. Extensometer systems are classified on the basis of the magnitude of their errors.  
1.2 Because strain is a dimensionless quantity, this document can be used for extensometers based on either SI or US customary units of displacement.  
Note 1: Bonded resistance strain gauges directly bonded to a specimen cannot be calibrated or verified with the apparatus described in this practice for the verification of extensometers having definite gauge points. (See procedures as described in Test Methods E251.)  
1.3 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use.

SIGNIFICANCE AND USE
4.1 Testing machines that apply and indicate force are used in many industries, in many ways. They may be used in a research laboratory to measure material properties, and in a production line to qualify a product for shipment. No matter what the end use of the machine may be, it is necessary for users to know that the amount of force applied and indicated is traceable to the International System of Units (SI) through a National Metrology Institute (NMI). The procedures in Practices E4 may be used to verify these machines so that the indicated forces are traceable to the SI. A key element of traceability to the SI is that the devices used in the verification have known force characteristics, and have been calibrated in accordance with Practice E74.  
4.2 The procedures in Practices E4 may be used by those using, manufacturing, and providing calibration service for testing machines and related instrumentation.
SCOPE
1.1 These practices cover procedures for the force verification, by means of standard calibration devices, of tension or compression, or both, static or quasi-static testing machines (which may, or may not, have force-indicating systems). These practices are not intended to be complete purchase specifications for testing machines. Testing machines may be verified by one of the three following methods or combination thereof:  
1.1.1 Use of standard weights,  
1.1.2 Use of equal-arm balances and standard weights, or  
1.1.3 Use of elastic calibration devices.  
Note 1: These practices do not cover the verification of all types of testing machines designed to measure forces, for example, the constant-rate-of-loading type which operates on the inclined-plane principle. This type of machine may be verified as directed in the applicable appendix of Specification D76/D76M.  
1.2 The procedures of 1.1.1 – 1.1.3 apply to the verification of the force-indicating systems associated with the testing machine, such as a scale, dial, marked or unmarked recorder chart, digital display, etc. In all cases the buyer/owner/user must designate the force-indicating system(s) to be verified and included in the report.  
1.3 Units—The values stated in either SI units or inch-pound units are to be regarded separately as standard. The values stated in each system may not be exact equivalents; therefore, each system shall be used independently of the other. Combining values from the two systems may result in non-conformance with the standard.  
1.3.1 Other customary force units may be used with this standard such as the kilogram-force (kgf) which is often used with hardness testing machines  
1.4 Forces indicated on displays/printouts of testing machine data systems—be they instantaneous, delayed, stored, or retransmitted—which are verified with provisions of 1.1.1, 1.1.2, or 1.1.3, and are within the ±1 % accuracy requirement, comply with Practices E4.  
1.5 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use.

SIGNIFICANCE AND USE
4.1 Testing machines that apply and measure displacement are used in many industries. They may be used in research laboratories to determine material properties, and in production lines to qualify products for shipment. The displacement measuring devices integral to the testing machines may be used for measurement of crosshead or actuator displacement over a defined range of operation. The accuracy of the displacement value shall be traceable to the National Institute of Standards and Technology (NIST) or another recognized National Laboratory. Practices E2309 provides a procedure to verify these machines and systems, in order that the measured displacement values may be traceable. A key element to having traceability is that the devices used in the verification produce known displacement characteristics, and have been calibrated in accordance with adequate calibration standards.
SCOPE
1.1 These practices cover procedures and requirements for the calibration and verification of displacement measuring systems by means of standard calibration devices for static and quasi-static testing machines. This practice is not intended to be complete purchase specifications for testing machines or displacement measuring systems. Displacement measuring systems are not intended to be used for the determination of strain. See Practice E83.  
1.2 These procedures apply to the verification of the displacement measuring systems associated with the testing machine, such as a scale, dial, marked or unmarked recorder chart, digital display, etc. In all cases the buyer/owner/user must designate the displacement-measuring system(s) to be verified.  
1.3 The values stated in either SI units or inch-pound units are to be regarded separately as standard. The values stated in each system may not be exact equivalents; therefore, each system shall be used independently of the other. Combining values from the two systems may result in non-conformance with the standard.  
1.4 Displacement values indicated on displays/printouts of testing machine data systems—be they instantaneous, delayed, stored, or retransmitted—which are within the Classification criteria listed in Table 1, comply with Practices E2309/E2309M.  
1.5 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use.

SIGNIFICANCE AND USE
4.1 Testing machines that apply and indicate torque are used in many industries, in many ways. They may be used in a research laboratory to measure material properties, and in a production line to qualify a product for shipment. No matter what the end use of the machine may be, it is necessary for users to know the amount of torque that is applied, and that the accuracy of the torque value is traceable to the SI. This standard provides a procedure to verify these machines and devices, in order that the indicated torque values may be traceable. A key element to having metrological traceability is that the devices used in the calibration produce known torque characteristics, and have been calibrated in accordance with Practice E2428.  
4.2 This standard may be used by those using, those manufacturing, and those providing calibration service for torque capable testing machines or devices and related instrumentation.
SCOPE
1.1 This practice covers procedures and requirements for the calibration of torque for static and quasi-static torque capable testing machines. These may, or may not, have torque indicating systems and include those devices used for the calibration of hand torque tools. Testing machines may be calibrated by one of the three following methods or combination thereof:  
1.1.1 Use of standard weights and lever arms.  
1.1.2 Use of elastic torque measuring devices.  
1.1.3 Use of elastic force measuring devices and lever arms.  
1.1.4 Any of the methods require a specific uncertainty of measurement, displaying metrological traceability to The International System of Units (SI).
Note 1: – for further definition of the term metrological traceability, refer to the latest revision of JCGM 200: International vocabulary of metrology — Basic and general concepts and associated terms (VIM).  
1.2 The procedures of 1.1.1, 1.1.2, and 1.1.3 apply to the calibration of the torque-indicating systems associated with the testing machine, such as a scale, dial, marked or unmarked recorder chart, digital display, etc. In all cases the buyer/owner/user must designate the torque-indicating system(s) to be calibrated and included in the report.  
1.3 Since conversion factors are not required in this practice, either english units, metric units, or SI units can be used as the standard.  
1.4 Torque values indicated on displays/printouts of testing machine data systems—be they instantaneous, delayed, stored, or retransmitted—which are calibrated with provisions of 1.1.1, 1.1.2 or 1.1.3 or a combination thereof, and are within the ±1 % of reading accuracy requirement, comply with this practice.  
1.5 The following applies to all specified limits in this standard: For purposes of determining conformance with these specifications, an observed value or a calculated value shall be rounded “to the nearest unit” in the last right-hand digit used in expressing the specification limit, in accordance with the rounding method of Practice E29, for Using Significant Digits in Test Data to Determine Conformance with Specifications.  
1.6 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use.

SIGNIFICANCE AND USE
4.1 Testing machines that apply and indicate force are used in many industries, in many ways. They may be used in a research laboratory to measure material properties, and in a production line to qualify a product for shipment. No matter what the end use of the machine may be, it is necessary for users to know that the amount of force applied and indicated is traceable to the International System of Units (SI) through a National Metrology Institute (NMI). The procedures in Practices E4 may be used to verify these machines so that the indicated forces are traceable to the SI. A key element of traceability to the SI is that the devices used in the verification have known force characteristics, and have been calibrated in accordance with Practice E74.  
4.2 The procedures in Practices E4 may be used by those using, manufacturing, and providing calibration service for testing machines and related instrumentation.
SCOPE
1.1 These practices cover procedures for the force verification, by means of standard calibration devices, of tension or compression, or both, static or quasi-static testing machines (which may, or may not, have force-indicating systems). These practices are not intended to be complete purchase specifications for testing machines. Testing machines may be verified by one of the three following methods or combination thereof:  
1.1.1 Use of standard weights,  
1.1.2 Use of equal-arm balances and standard weights, or  
1.1.3 Use of elastic calibration devices.  
Note 1: These practices do not cover the verification of all types of testing machines designed to measure forces, for example, the constant-rate-of-loading type which operates on the inclined-plane principle. This type of machine may be verified as directed in the applicable appendix of Specification D76/D76M.  
1.2 The procedures of 1.1.1 – 1.1.3 apply to the verification of the force-indicating systems associated with the testing machine, such as a scale, dial, marked or unmarked recorder chart, digital display, etc. In all cases the buyer/owner/user must designate the force-indicating system(s) to be verified and included in the report.  
1.3 The values stated in inch-pound units are to be regarded as standard. The values given in parentheses are mathematical conversions to SI units that are provided for information only and are not considered standard.  
1.3.1 Since conversion factors are not required in this practice, either inch-pound units, SI units, or metric values can be used as the standard.  
1.4 Forces indicated on displays/printouts of testing machine data systems—be they instantaneous, delayed, stored, or retransmitted—which are verified with provisions of 1.1.1, 1.1.2, or 1.1.3, and are within the ±1 % accuracy requirement, comply with Practices E4.  
1.5 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use.

SIGNIFICANCE AND USE
4.1 Testing machines that apply and indicate torque are in general use in many industries. Practice E2624 has been written to provide a practice for the torque verification of these machines. A necessary element in Practice E2624 is the use of devices whose torque characteristics are known to be metrologically traceable to the International System of Units (SI). Practice E2428 describes how these devices are to be calibrated. The procedures are useful to users of testing machines, manufacturers and providers of torque measuring instruments, calibration laboratories that provide calibration services and documents of metrological traceability, and service organizations using devices to verify testing machines.
SCOPE
1.1 The purpose of this practice is to specify the procedure for the calibration of torque transducers.
Note 1: Verification by deadweight and a lever arm is an acceptable method of verifying the torque indication of a testing machine. Tolerances for weights used are tabulated in Practice E2624; methods for calibration of the weights are given in NIST Technical Note 577, Methods of Calibrating Weights for Piston Gages.2  
1.2 The values stated in SI units are to be regarded as standard. Other metric and inch-pound values are regarded as equivalent when required.  
1.3 This practice is intended for the calibration of static torque measuring instruments. The practice is not applicable for dynamic or high-speed torque calibrations or measurements, nor can the results of calibrations performed in accordance with this practice be assumed valid for dynamic or high speed torque measurements.  
1.4 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use.

SIGNIFICANCE AND USE
4.1 Material testing requires repeatable and predictable testing machine speed. The speed measuring devices integral to the testing machines may be used for measurement of crosshead speed over a defined range of operation. The accuracy of the speed value shall be traceable to a National or International Standards Laboratory. Practices E2658 provides procedures to verify testing machines, in order that the indicated speed values may be traceable. A key element to having traceability is that the devices used in the verification produce known speed characteristics, and have been calibrated in accordance with adequate calibration standards.  
4.2 Verification of testing machine speed at a minimum consists of either or both of the following options:  
4.2.1 Verifying the capability of the testing machine to move the crosshead at the speed selected.  
4.2.2 Verifying the capability of the testing machine to adequately indicate the speed of the crosshead.  
4.3 Where applicable, determine the testing machine's ramp-to-speed condition. This condition can be significant especially when verifying fast speeds or testing conditions with very short testing durations.  
4.4 This procedure will establish the relationship between the actual crosshead speed and the testing machine indicated speed and or selected setting. It is this relationship that will allow confidence in the reported displacement over time data acquired by the testing machine during use.
Note 1: Many material tests never reach the desired test speed. Unless the actual data from the material test is examined, it is often impossible to know if the test speed has been reached or is repeatable from test to test.
SCOPE
1.1 These practices cover procedures and requirements for the calibration and verification of testing machine speed by means of standard calibration devices. This practice is not intended to be complete purchase specifications for testing machines.  
1.2 These practices apply to the verification of the speed application and measuring systems associated with the testing machine, such as a scale, dial, marked or unmarked recorder chart, digital display, setting, etc. In all cases the buyer/owner/user must designate the speed-measuring system(s) to be verified.  
1.3 These practices give guidance, recommendations, and examples, specific to electro-mechanical testing machines. The practice may also be used to verify actuator speed for hydraulic testing machines.  
1.4 This standard cannot be used to verify cycle counting or frequency related to cyclic fatigue testing applications.  
1.5 Since conversion factors are not required in this practice, either SI units (mm/min), or English [in/min], can be used as the standard.  
1.6 Speed measurement values and or settings on displays/printouts of testing machine data systems-be they instantaneous, delayed, stored, or retransmitted-which are within the Classification criteria listed in Table 1, comply with Practices E2658.  
1.7 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use.

SIGNIFICANCE AND USE
4.1 Testing machines that apply and indicate torque are in general use in many industries. Practice E2624 has been written to provide a practice for the torque verification of these machines. A necessary element in Practice E2624 is the use of devices whose torque characteristics are known to be traceable to the International System of Units (SI). Practice E2428 describes how these devices are to be calibrated. The procedures are useful to users of testing machines, manufacturers and providers of torque measuring instruments, calibration laboratories that provide calibration services and documents of metrological traceability, and service organizations using devices to verify testing machines.
SCOPE
1.1 This practice is to specify procedure for the calibration of elastic torque-measuring instruments.
Note 1: Verification by deadweight and a lever arm is an acceptable method of verifying the torque indication of a torque testing machine. Tolerances for weights used are tabulated in Practice E2624; methods for calibration of the weights are given in NIST Technical Note 577, Methods of Calibrating Weights for Piston Gages.2  
1.2 The values stated in SI units are to be regarded as standard. Other metric and inch-pound values are regarded as equivalent when required.  
1.3 This practice is intended for the calibration of static torque measuring instruments. The practice is not applicable for dynamic or high-speed torque calibrations or measurements, nor can the results of calibrations performed in accordance with this practice be assumed valid for dynamic or high speed torque measurements.  
1.4 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use.

SIGNIFICANCE AND USE
4.1 Testing machines that apply and indicate torque are in general use in many industries. Practice E2624 has been written to provide a practice for the torque verification of these machines. A necessary element in Practice E2624 is the use of devices whose torque characteristics are known to be traceable to national standards. Practice E2428 describes how these devices are to be calibrated. The procedures are useful to users of torque testing machines, manufacturers and providers of torque measuring instruments, calibration laboratories that provide calibration services and documents, and service organizations using devices to verify torque testing machines.
SCOPE
1.1 This practice is to specify procedure for the calibration of elastic torque-measuring instruments.
Note 1: Verification by deadweight and a lever arm is an acceptable method of verifying the torque indication of a torque testing machine. Tolerances for weights used are tabulated in Practice E2624; methods for calibration of the weights are given in NIST Technical Note 577, Methods of Calibrating Weights for Piston Gages.2  
1.2 The values stated in either SI units or inch-pound units are to be regarded separately as standard. The values stated in each system may not be exact equivalents; therefore, each system shall be used independently of the other. Combining values from the two systems may result in non-conformance with the standard.  
1.3 This practice is intended for the calibration of static torque measuring instruments. The practice is not applicable for dynamic or high-speed torque calibrations or measurements, nor can the results of calibrations performed in accordance with this practice be assumed valid for dynamic or high speed torque measurements.  
1.4 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use.

SIGNIFICANCE AND USE
4.1 It has been shown that bending stresses that inadvertently occur due to misalignment between the applied force and the specimen axes during the application of tensile and compressive forces can affect the test results. In recognition of this effect, some test methods include a statement limiting the misalignment that is permitted. The purpose of this practice is to provide a reference for test methods and practices that require the application of tensile or compressive forces under conditions where alignment is important. The objective is to implement the use of common terminology and methods for verification of alignment of testing machines, associated components and test specimens.  
4.2 Alignment verification intervals when required are specified in the methods or practices that require the alignment verification. Certain types of testing can provide an indication of the current alignment condition of a testing frame with each specimen tested. If a test method requires alignment verification, the frequency of the alignment verification should capture all the considerations that is, time interval, changes to the testing frame and when applicable, current indicators of the alignment condition through test results.  
4.3 Whether or not to improve axiality should be a matter of negotiation between the material producer and the user.
SCOPE
1.1 Included in this practice are methods covering the determination of the amount of bending that occurs during the application of tensile and compressive forces to notched and unnotched test specimens during routine testing in the elastic range. These methods are particularly applicable to the force levels normally used for tension testing, creep testing, and uniaxial fatigue testing. The principal objective of this practice is to assess the amount of bending exerted upon a test specimen by the ordinary components assembled into a materials testing machine, during routine tests.  
1.2 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.

SIGNIFICANCE AND USE
4.1 It has been shown that bending stresses that inadvertently occur due to misalignment between the applied force and the specimen axes during the application of tensile and compressive forces can affect the test results. In recognition of this effect, some test methods include a statement limiting the misalignment that is permitted. The purpose of this practice is to provide a reference for test methods and practices that require the application of tensile or compressive forces under conditions where alignment is important. The objective is to implement the use of common terminology and methods for verification of alignment of testing machines, associated components and test specimens.  
4.2 Alignment verification intervals when required are specified in the methods or practices that require the alignment verification. Certain types of testing can provide an indication of the current alignment condition of a testing frame with each specimen tested. If a test method requires alignment verification, the frequency of the alignment verification should capture all the considerations i.e. time interval, changes to the testing frame and when applicable, current indicators of the alignment condition through test results.  
4.3 Whether or not to improve axiality should be a matter of negotiation between the material producer and the user.
SCOPE
1.1 Included in this practice are methods covering the determination of the amount of bending that occurs during the application of tensile and compressive forces to notched and unnotched test specimens during routine testing in the elastic range. These methods are particularly applicable to the force levels normally used for tension testing, creep testing, and uniaxial fatigue testing. The principal objective of this practice is to assess the amount of bending exerted upon a test specimen by the ordinary components assembled into a materials testing machine, during routine tests.

SIGNIFICANCE AND USE
4.1 Testing machines that apply and indicate force are used in many industries, in many ways. They may be used in a research laboratory to measure material properties, and in a production line to qualify a product for shipment. No matter what the end use of the machine may be, it is necessary for users to know that the amount of force applied and indicated is traceable to the International System of Units (SI) through a National Metrology Institute (NMI). The procedures in Practices E4 may be used to verify these machines so that the indicated forces are traceable to the SI. A key element of traceability to the SI is that the devices used in the verification have known force characteristics, and have been calibrated in accordance with Practice E74.  
4.2 The procedures in Practices E4 may be used by those using, manufacturing, and providing calibration service for testing machines and related instrumentation.
SCOPE
1.1 These practices cover procedures for the force verification, by means of standard calibration devices, of tension or compression, or both, static or quasi-static testing machines (which may, or may not, have force-indicating systems). These practices are not intended to be complete purchase specifications for testing machines. Testing machines may be verified by one of the three following methods or combination thereof:  
1.1.1 Use of standard weights,  
1.1.2 Use of equal-arm balances and standard weights, or  
1.1.3 Use of elastic calibration devices.  
Note 1: These practices do not cover the verification of all types of testing machines designed to measure forces, for example, the constant-rate-of-loading type which operates on the inclined-plane principle. This type of machine may be verified as directed in the applicable appendix of Specification D76.  
1.2 The procedures of 1.1.1 – 1.1.3 apply to the verification of the force-indicating systems associated with the testing machine, such as a scale, dial, marked or unmarked recorder chart, digital display, etc. In all cases the buyer/owner/user must designate the force-indicating system(s) to be verified and included in the report.  
1.3 The values stated in inch-pound units are to be regarded as standard. The values given in parentheses are mathematical conversions to SI units that are provided for information only and are not considered standard.  
1.3.1 Since conversion factors are not required in this practice, either inch-pound units, SI units, or metric values can be used as the standard.  
1.4 Forces indicated on displays/printouts of testing machine data systems—be they instantaneous, delayed, stored, or retransmitted—which are verified with provisions of 1.1.1, 1.1.2, or 1.1.3, and are within the ±1 % accuracy requirement, comply with Practices E4.  
1.5 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use.

ABSTRACT
This practice defines a reference axis for each of the two principal types of rosette configurations and the equations used for three-element strain gage rosette data analysis. The primary uses of this analysis procedure are to determine the directions and magnitudes of the principal surface strains, and to determine residual stresses. This is important for consistency in reporting results and for avoiding ambiguity in data analysis, especially when computers are used. There are several possible sets of equations, but the set presented herein is perhaps the most common.
SCOPE
1.1 The two primary uses of three-element strain gage rosettes are (a) to determine the directions and magnitudes of the principal surface strains and (b) to determine residual stresses. Residual stresses are treated in a separate ASTM standard, Test Method E837. This practice defines a reference axis for each of the two principal types of rosette configurations used and presents equations for data analysis. This is important for consistency in reporting results and for avoiding ambiguity in data analysis—especially when computers are used. There are several possible sets of equations, but the set presented here is perhaps the most common.

SIGNIFICANCE AND USE
4.1 Strain gages are the most widely used devices for measuring strains and for evaluating stresses in structures. In many applications there are often cyclic loads which can cause strain gage failure. Performance parameters of strain gages are affected by both the materials from which they are made and their geometric design.  
4.2 The determination of most strain gage parameters requires mechanical testing that is destructive. Since gages tested for fatigue life cannot be used again, it is necessary to treat data statistically. In general, longer and wider gages with lower resistances will have greater fatigue life. Optional additions to gages (integral leads are an example) will often reduce fatigue life.  
4.3 To be used, strain gages must be bonded to a structure. Good results, particularly in a fatigue environment, depend heavily on the materials used to clean the bonding surface, to bond the gage, and to provide a protective coating. Skill of the installer is another major factor in success. Finally, instrumentation systems must be carefully selected and calibrated to ensure that they do not unduly degrade the performance of the gages.  
4.4 This test method encompasses only fully reversed strain cycles.  
4.5 Fatigue failure of a strain gage may not involve visible cracking or fracture of the gage, but merely sufficient zero shift to compromise the accuracy of the gage output for static strain components.
SCOPE
1.1 This test method covers a uniform procedure for the determination of strain gage fatigue life at ambient temperature. A suggested testing equipment design is included.  
1.2 This test method does not apply to force transducers or extensometers that use bonded resistance strain gages as sensing elements.  
1.3 Strain gages are part of a complex system that includes structure, adhesive, gage, lead wires, instrumentation, and (often) environmental protection. As a result, many things affect the performance of strain gages, including user technique. A further complication is that strain gages, once installed, normally cannot be reinstalled in another location. Therefore, it is not possible to calibrate individual strain gages; performance characteristics are normally presented on a statistical basis.  
1.4 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to its use.

SIGNIFICANCE AND USE
4.1 Strain gages are the most widely used devices for the determination of materials, properties and for analyzing stresses in structures. However, performance parameters of strain gages are affected by both the materials from which they are made and their geometric design. These test methods detail the minimum information that must accompany strain gages if they are to be used with acceptable accuracy of measurement.  
4.2 Most performance parameters of strain gages require mechanical testing that is destructive. Since test gages cannot be used again, it is necessary to treat data statistically and then apply values to the remaining population from the same lot or batch. Failure to acknowledge the resulting uncertainties can have serious repercussions. Resistance measurement is non-destructive and can be made for each gage.  
4.3 Properly designed and manufactured strain gages, whose properties have been accurately determined and with appropriate uncertainties applied, represent powerful measurement tools. They can determine small dimensional changes in structures with excellent accuracy, far beyond that of other known devices. It is important to recognize, however, that individual strain gages cannot be calibrated. If calibration and traceability to a standard are required, strain gages should not be employed.  
4.4 To be used, strain gages must be bonded to a structure. Good results depend heavily on the materials used to clean the bonding surface, to bond the gage, and to provide a protective coating. Skill of the installer is another major factor in success. Finally, instrumentation systems must be carefully designed to assure that they do not unduly degrade the performance of the gages. In many cases, it is impossible to achieve this goal. If so, allowance must be made when considering accuracy of data. Test conditions can, in some instances, be so severe that error signals from strain gage systems far exceed those from the structural deformations to be mea...
SCOPE
1.1 The purpose of these test methods are to provide uniform test methods for the determination of strain gage performance characteristics. Suggested testing equipment designs are included.  
1.2 Test Methods E251 describes methods and procedures for determining five strain gage parameters:    
Section  
Part I—General Requirements  
7  
Part II—Resistance at a Reference Temperature  
8  
Part III—Gage Factor at a Reference Temperature  
9  
Part IV—Temperature Coefficient of Gage Factor  
10  
Part V—Transverse Sensitivity  
11  
Part VI—Thermal Output  
12  
1.3 Strain gages are very sensitive devices with essentially infinite resolution. Their response to strain, however, is low and great care must be exercised in their use. The performance characteristics identified by these test methods must be known to an acceptable accuracy to obtain meaningful results in field applications.  
1.3.1 Strain gage resistance is used to balance instrumentation circuits and to provide a reference value for measurements since all data are related to a change in the gage resistance from a known reference value.  
1.3.2 Gage factor is the transfer function of a strain gage. It relates resistance change in the gage and strain to which it is subjected. Accuracy of strain gage data can be no better than the precision of the gage factor.  
1.3.3 Changes in gage factor as temperature varies also affect accuracy although to a much lesser degree since variations are usually small.  
1.3.4 Transverse sensitivity is a measure of the strain gage's response to strains perpendicular to its measurement axis. Although transverse sensitivity is usually much less than 10 % of the gage factor, large errors can occur if the value is not known with reasonable precision.  
1.3.5 Thermal output is the response of a strain gage to temperature changes. Thermal output is an additive (not multiplicative) error. Therefore, it can...

SIGNIFICANCE AND USE
4.1 Methods and procedures used in installing bonded resistance strain gages can have significant effects upon the performance of those sensors. Optimum and reproducible detection of surface deformation requires appropriate and consistent surface preparation, mounting procedures, and verification techniques.
SCOPE
1.1 This guide provides guidelines for installing bonded resistance strain gages. It is not intended to be used for bulk or diffused semiconductor gages. This document pertains only to adhesively bonded strain gages.  
1.2 The values stated in inch-pound units are to be regarded as standard. The values given in parentheses are mathematical conversions to SI units that are provided for information only and are not considered standard.  
1.3 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use.

SIGNIFICANCE AND USE
4.1 The use of this guide is voluntary and is intended for use as a procedures guide for selection and application of specific types of strain gages for high-temperature installations. No attempt is made to restrict the type of strain gage types or concepts to be chosen by the user. The provisions of this guide may be invoked in specifications and procedures by specifying those which shall be considered mandatory for the purpose of the specific application. When so invoked, the user shall include in the work statement a notation that provisions of this guide shown as recommendation shall be considered mandatory for the purposes of the specification or procedure concerned, and shall include a statement of any exceptions to or modifications of the affected provisions of this guide.
SCOPE
1.1 This guide covers the selection and application of strain gages for the measurement of static strain up to and including the temperature range from 425 to 650°C (800 to 1200°F). This guide reflects some current state-of-the-art techniques in high temperature strain measurement, and will be expanded and updated as new technology develops.  
1.2 This guide assumes that the user is familiar with the use of bonded strain gages and associated signal conditioning and instrumentation as discussed in  (1)  and (2). 2 The strain measuring systems described are those that have proven effective in the temperature range of interest and were available at the time of issue of this guide. It is not the intent of this guide to limit the user to one of the gage types described nor is it the intent to specify the type of system to be used for a specific application. However, in using any strain measuring system including those described, the proposer must be able to demonstrate the capability of the proposed system to meet the selection criteria provided in Section 5 and the needs of the specific application.  
1.3 The devices and techniques described in this guide may be applicable at temperatures above and below the range noted, and for making dynamic strain measurements at high temperatures with proper precautions. The gage manufacturer should be consulted for recommendations and details of such applications.  
1.4 The references are a part of this guide to the extent specified in the text.  
1.5 The values stated in metric (SI) units are to be regarded as the standard. The values given in parentheses are for informational purposes only.  
1.6 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use.

SIGNIFICANCE AND USE
4.1 Testing machines that apply and indicate force are in general use in many industries. Practices E4 has been written to provide a practice for the force verification of these machines. A necessary element in Practices E4 is the use of devices whose force characteristics are known to be traceable to national standards. Practice E74 describes how these devices are to be calibrated. The procedures are useful to users of testing machines, manufacturers and providers of force measuring instruments, calibration laboratories that provide the calibration of the instruments and the documents of traceability, and service organizations that use the devices to verify testing machines.
SCOPE
1.1 The purpose of this practice is to specify procedures for the calibration of force-measuring instruments. Procedures are included for the following types of instruments:  
1.1.1 Elastic force-measuring instruments, and  
1.1.2 Force-multiplying systems, such as balances and small platform scales. Note 1—Verification by deadweight loading is also an acceptable method of verifying the force indication of a testing machine. Tolerances for weights for this purpose are given in Practices E4; methods for calibration of the weights are given in NIST Technical Note 577, Methods of Calibrating Weights for Piston Gages.2  
1.2 The values stated in SI units are to be regarded as the standard. Other metric and inch-pound values are regarded as equivalent when required.  
1.3 This practice is intended for the calibration of static force measuring instruments. It is not applicable for dynamic or high speed force calibrations, nor can the results of calibrations performed in accordance with this practice be assumed valid for dynamic or high speed force measurements.  
1.4 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use.

SIGNIFICANCE AND USE
4.1 Testing machines that apply and indicate force are used in many industries, in many ways. They may be used in a research laboratory to measure material properties, and in a production line to qualify a product for shipment. No matter what the end use of the machine may be, it is necessary for users to know the amount of force that is applied and indicated, and that the accuracy of the force is traceable to the National Institute of Standards and Technology (NIST), formerly NBS. Practices E4 provides a procedure to verify these machines, in order that the indicated forces may be traceable. A key element to this NIST traceability is that the devices used in the verification have known force characteristics, and have been calibrated in accordance with Practice E74.  
4.2 The procedures in Practices E4 may be used by those using, manufacturing, and providing calibration service for testing machines and related instrumentation.
SCOPE
1.1 These practices cover procedures for the force verification, by means of standard calibration devices, of tension or compression, or both, static or quasi-static testing machines (which may, or may not, have force-indicating systems). These practices are not intended to be complete purchase specifications for testing machines. Testing machines may be verified by one of the three following methods or combination thereof:  
1.1.1 Use of standard weights,  
1.1.2 Use of equal-arm balances and standard weights, or  
1.1.3 Use of elastic calibration devices. Note 1—These practices do not cover the verification of all types of testing machines designed to measure forces, for example, the constant-rate-of-loading type which operates on the inclined-plane principle. This type of machine may be verified as directed in the applicable appendix of Specification D76.  
1.2 The procedures of 1.1.1-1.1.3 apply to the verification of the force-indicating systems associated with the testing machine, such as a scale, dial, marked or unmarked recorder chart, digital display, etc. In all cases the buyer/owner/user must designate the force-indicating system(s) to be verified and included in the report.  
1.3 The values stated in inch-pound units are to be regarded as standard. The values given in parentheses are mathematical conversions to SI units that are provided for information only and are not considered standard.  
1.3.1 Since conversion factors are not required in this practice, either inch-pound units, SI units, or metric values can be used as the standard.  
1.4 Forces indicated on displays/printouts of testing machine data systems—be they instantaneous, delayed, stored, or retransmitted—which are verified with provisions of 1.1.1, 1.1.2, or 1.1.3, and are within the ±1 % accuracy requirement, comply with Practices E4.  
1.5 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use.

SIGNIFICANCE AND USE
4.1 Testing machines that apply and indicate force are in general use in many industries. Practices E4 has been written to provide a practice for the force verification of these machines. A necessary element in Practices E4 is the use of devices whose force characteristics are known to be traceable to national standards. Practice E74 describes how these devices are to be calibrated. The procedures are useful to users of testing machines, manufacturers and providers of force measuring instruments, calibration laboratories that provide the calibration of the instruments and the documents of traceability, and service organizations that use the devices to verify testing machines.
SCOPE
1.1 The purpose of this practice is to specify procedures for the calibration of force-measuring instruments. Procedures are included for the following types of instruments:  
1.1.1 Elastic force-measuring instruments, and  
1.1.2 Force-multiplying systems, such as balances and small platform scales. Note 1—Verification by deadweight loading is also an acceptable method of verifying the force indication of a testing machine. Tolerances for weights for this purpose are given in Practices E4; methods for calibration of the weights are given in NIST Technical Note 577, Methods of Calibrating Weights for Piston Gages.2  
1.2 The values stated in SI units are to be regarded as the standard. Other metric and inch-pound values are regarded as equivalent when required.  
1.3 This practice is intended for the calibration of static force measuring instruments. It is not applicable for dynamic or high speed force calibrations, nor can the results of calibrations performed in accordance with this practice be assumed valid for dynamic or high speed force measurements.  
1.4 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use.

SIGNIFICANCE AND USE
4.1 Testing machines that apply and indicate force are in general use in many industries. Practices E4 has been written to provide a practice for the force verification of these machines. A necessary element in Practices E4 is the use of devices whose force characteristics are known to be traceable to national standards. Practice E74 describes how these devices are to be calibrated. The procedures are useful to users of testing machines, manufacturers and providers of force measuring instruments, calibration laboratories that provide the calibration of the instruments and the documents of traceability, and service organizations that use the devices to verify testing machines.
SCOPE
1.1 The purpose of this practice is to specify procedures for the calibration of force-measuring instruments. Procedures are included for the following types of instruments:  
1.1.1 Elastic force-measuring instruments, and  
1.1.2 Force-multiplying systems, such as balances and small platform scales. Note 1—Verification by deadweight loading is also an acceptable method of verifying the force indication of a testing machine. Tolerances for weights for this purpose are given in Practices E4; methods for calibration of the weights are given in NIST Technical Note 577, Methods of Calibrating Weights for Piston Gages.2  
1.2 The values stated in SI units are to be regarded as the standard. Other metric and inch-pound values are regarded as equivalent when required.  
1.3 This practice is intended for the calibration of static force measuring instruments. It is not applicable for dynamic or high speed force calibrations, nor can the results of calibrations performed in accordance with this practice be assumed valid for dynamic or high speed force measurements.  
1.4 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use.

SIGNIFICANCE AND USE
4.1 It has been shown that bending stresses that inadvertently occur due to misalignment between the applied force and the specimen axes during the application of tensile and compressive forces can affect the test results. In recognition of this effect, some test methods include a statement limiting the misalignment that is permitted. The purpose of this practice is to provide a reference for test methods and practices that require the application of tensile or compressive forces under conditions where alignment is important. The objective is to implement the use of common terminology and methods for verification of alignment of testing machines, associated components and test specimens.  
4.2 Alignment verification intervals when required are specified in the methods or practices that require the alignment verification. Certain types of testing can provide an indication of the current alignment condition of a testing frame with each specimen tested. If a test method requires alignment verification, the frequency of the alignment verification should capture all the considerations i.e. time interval, changes to the testing frame and when applicable, current indicators of the alignment condition through test results.  
4.3 Whether or not to improve axiality should be a matter of negotiation between the material producer and the user.
SCOPE
1.1 Included in this practice are methods covering the determination of the amount of bending that occurs during the application of tensile and compressive forces to notched and unnotched test specimens during routine testing in the elastic range. These methods are particularly applicable to the force levels normally used for tension testing, creep testing, and uniaxial fatigue testing. The principal objective of this practice is to assess the amount of bending exerted upon a test specimen by the ordinary components assembled into a materials testing machine, during routine tests.

SIGNIFICANCE AND USE
It has been shown that bending stresses that inadvertently occur due to misalignment between the applied force and the specimen axes during the application of tensile and compressive forces can affect the test results. In recognition of this effect, some test methods include a statement limiting the misalignment that is permitted. The purpose of this practice is to provide a reference for test methods and practices that require the application of tensile or compressive forces under conditions where alignment is important. The objective is to implement the use of common terminology and methods for verification of alignment of testing machines, associated components and test specimens.
Alignment verification intervals when required are specified in the methods or practices that require the alignment verification. Certain types of testing can provide an indication of the current alignment condition of a testing frame with each specimen tested. If a test method requires alignment verification, the frequency of the alignment verification should capture all the considerations i.e. time interval, changes to the testing frame and when applicable, current indicators of the alignment condition through test results.
Whether or not to improve axiality should be a matter of negotiation between the material producer and the user.
SCOPE
1.1 Included in this practice are methods covering the determination of the amount of bending that occurs during the application of tensile and compressive forces to notched and unnotched test specimens during routine testing in the elastic range. These methods are particularly applicable to the force levels normally used for tension testing, creep testing, and uniaxial fatigue testing. The principal objective of this practice is to assess the amount of bending exerted upon a test specimen by the ordinary components assembled into a materials testing machine, during routine tests.

SIGNIFICANCE AND USE
Material testing requires repeatable and predictable testing machine speed. The speed measuring devices integral to the testing machines may be used for measurement of crosshead speed over a defined range of operation. The accuracy of the speed value shall be traceable to a National or International Standards Laboratory. Practices E2658 provides procedures to verify testing machines, in order that the indicated speed values may be traceable. A key element to having traceability is that the devices used in the verification produce known speed characteristics, and have been calibrated in accordance with adequate calibration standards.  
Verification of testing machine speed at a minimum consists of either or both of the following options:
Verifying the capability of the testing machine to move the crosshead at the speed selected.
Verifying the capability of the testing machine to adequately indicate the speed of the crosshead.
Where applicable, determine the testing machine's ramp-to-speed condition. This condition can be significant especially when verifying fast speeds or testing conditions with very short testing durations.
This procedure will establish the relationship between the actual crosshead speed and the testing machine indicated speed and or selected setting. It is this relationship that will allow confidence in the reported displacement over time data acquired by the testing machine during use.
Note 1—Many material tests never reach the desired test speed. Unless the actual data from the material test is examined, it is often impossible to know if the test speed has been reached or is repeatable from test to test.
SCOPE
1.1 These practices cover procedures and requirements for the calibration and verification of testing machine speed by means of standard calibration devices. This practice is not intended to be complete purchase specifications for testing machines.
1.2 These practices apply to the verification of the speed application and measuring systems associated with the testing machine, such as a scale, dial, marked or unmarked recorder chart, digital display, setting, etc. In all cases the buyer/owner/user must designate the speed-measuring system(s) to be verified.
1.3 These practices give guidance, recommendations, and examples, specific to electro-mechanical testing machines. The practice may also be used to verify actuator speed for hydraulic testing machines.
1.4 This standard cannot be used to verify cycle counting or frequency related to cyclic fatigue testing applications.
1.5 Since conversion factors are not required in this practice, either SI units (mm/min), or English [in/min], can be used as the standard.
1.6 Speed measurement values and or settings on displays/printouts of testing machine data systems-be they instantaneous, delayed, stored, or retransmitted-which are within the Classification criteria listed in Table 1, comply with Practices E2658.
1.7 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use.

SIGNIFICANCE AND USE
Testing machines that apply and measure displacement are used in many industries. They may be used in research laboratories to determine material properties, and in production lines to qualify products for shipment. The displacement measuring devices integral to the testing machines may be used for measurement of crosshead or actuator displacement over a defined range of operation. The accuracy of the displacement value shall be traceable to the National Institute of Standards and Technology (NIST) or another recognized National Laboratory. Practices E2309 provides a procedure to verify these machines and systems, in order that the measured displacement values may be traceable. A key element to having traceability is that the devices used in the verification produce known displacement characteristics, and have been calibrated in accordance with adequate calibration standards.
SCOPE
1.1 These practices cover procedures and requirements for the calibration and verification of displacement measuring systems by means of standard calibration devices for static and quasi-static testing machines. This practice is not intended to be complete purchase specifications for testing machines or displacement measuring systems. Displacement measuring systems are not intended to be used for the determination of strain. See Practice E83.
1.2 These procedures apply to the verification of the displacement measuring systems associated with the testing machine, such as a scale, dial, marked or unmarked recorder chart, digital display, etc. In all cases the buyer/owner/user must designate the displacement-measuring system(s) to be verified.
1.3 The values stated in either SI units or inch-pound units are to be regarded separately as standard. The values stated in each system may not be exact equivalents; therefore, each system shall be used independently of the other. Combining values from the two systems may result in non-conformance with the standard.
1.4 Displacement values indicated on displays/printouts of testing machine data systemsbe they instantaneous, delayed, stored, or retransmittedwhich are within the Classification criteria listed in Table 1, comply with Practices E2309/E2309M.
1.5 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use.

ABSTRACT
This practice covers procedures for the verification and classification of extensometer systems, but it is not intended to be a complete purchase specification. The practice is applicable only to instruments that indicate or record values that are proportional to changes in length corresponding to either tensile or compressive strain. Extensometer systems are classified on the basis of the magnitude of their errors. The apparatus for verifying extensometer systems shall provide a means for applying controlled displacements to a simulated specimen and for measuring these displacements accurately. Extensometer systems shall be classified in accordance with the requirements as to maximum error of strain indicated: Class A; Class B-1; Class B-2; Class C; Class D; and Class E. Extensometer systems shall be categorized in three types according to gage length: Type 1; Type 2; and Type 3. A verification procedure for extensometer systems shall be done in accordance with the specified requirements.
SCOPE
1.1 This practice covers procedures for the verification and classification of extensometer systems, but it is not intended to be a complete purchase specification. The practice is applicable only to instruments that indicate or record values that are proportional to changes in length corresponding to either tensile or compressive strain. Extensometer systems are classified on the basis of the magnitude of their errors.
1.2 Because strain is a dimensionless quantity, this document can be used for extensometers based on either SI or US customary units of displacement.
Note 1—Bonded resistance strain gauges directly bonded to a specimen cannot be calibrated or verified with the apparatus described in this practice for the verification of extensometers having definite gauge points. (See procedures as described in Test Methods E251.)  
1.3 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use.

SIGNIFICANCE AND USE
Testing machines that apply and indicate force are used in many industries, in many ways. They may be used in a research laboratory to measure material properties, and in a production line to qualify a product for shipment. No matter what the end use of the machine may be, it is necessary for users to know the amount of force that is applied and indicated, and that the accuracy of the force is traceable to the National Institute of Standards and Technology (NIST), formerly NBS. Practices E4 provides a procedure to verify these machines, in order that the indicated forces may be traceable. A key element to this NIST traceability is that the devices used in the verification have known force characteristics, and have been calibrated in accordance with Practice E74.
The procedures in Practices E4 may be used by those using, manufacturing, and providing calibration service for testing machines and related instrumentation.
SCOPE
1.1 These practices cover procedures for the force verification, by means of standard calibration devices, of tension or compression, or both, static or quasi-static testing machines (which may, or may not, have force-indicating systems). These practices are not intended to be complete purchase specifications for testing machines. Testing machines may be verified by one of the three following methods or combination thereof:
1.1.1 Use of standard weights,
1.1.2 Use of equal-arm balances and standard weights, or
1.1.3 Use of elastic calibration devices.
Note 1—These practices do not cover the verification of all types of testing machines designed to measure forces, for example, the constant-rate-of-loading type which operates on the inclined-plane principle. This type of machine may be verified as directed in the applicable appendix of Specification D76.  
1.2 The procedures of 1.1.1-1.1.3 apply to the verification of the force-indicating systems associated with the testing machine, such as a scale, dial, marked or unmarked recorder chart, digital display, etc. In all cases the buyer/owner/user must designate the force-indicating system(s) to be verified and included in the report.
1.3 The values stated in inch-pound units are to be regarded as standard. The values given in parentheses are mathematical conversions to SI units that are provided for information only and are not considered standard.
1.3.1 Since conversion factors are not required in this practice, either inch-pound units, SI units, or metric values can be used as the standard.
1.4 Forces indicated on displays/printouts of testing machine data systemsbe they instantaneous, delayed, stored, or retransmittedwhich are verified with provisions of 1.1.1, 1.1.2, or 1.1.3, and are within the ±1 % accuracy requirement, comply with Practices E4.
1.5 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use.

ABSTRACT
This practice covers procedures for the verification and classification of extensometer systems, but it is not intended to be a complete purchase specification. The practice is applicable only to instruments that indicate or record values that are proportional to changes in length corresponding to either tensile or compressive strain. Extensometer systems are classified on the basis of the magnitude of their errors. The apparatus for verifying extensometer systems shall provide a means for applying controlled displacements to a simulated specimen and for measuring these displacements accurately. Extensometer systems shall be classified in accordance with the requirements as to maximum error of strain indicated: Class A; Class B-1; Class B-2; Class C; Class D; and Class E. Extensometer systems shall be categorized in three types according to gage length: Type 1; Type 2; and Type 3. A verification procedure for extensometer systems shall be done in accordance with the specified requirements.
SCOPE
1.1 This practice covers procedures for the verification and classification of extensometer systems, but it is not intended to be a complete purchase specification. The practice is applicable only to instruments that indicate or record values that are proportional to changes in length corresponding to either tensile or compressive strain. Extensometer systems are classified on the basis of the magnitude of their errors.
1.2 Because strain is a dimensionless quantity, this document can be used for extensometers based on either SI or US customary units of displacement.
Note 1—Bonded resistance strain gauges directly bonded to a specimen cannot be calibrated or verified with the apparatus described in this practice for the verification of extensometers having definite gauge points. (See procedures as described in Test Methods E251.)  
1.3 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use.

SIGNIFICANCE AND USE
Testing machines that apply and indicate force are used in many industries, in many ways. They may be used in a research laboratory to measure material properties, and in a production line to qualify a product for shipment. No matter what the end use of the machine may be, it is necessary for users to know the amount of force that is applied and indicated, and that the accuracy of the force is traceable to the National Institute of Standards and Technology (NIST), formerly NBS. Practices E4 provides a procedure to verify these machines, in order that the indicated forces may be traceable. A key element to this NIST traceability is that the devices used in the verification have known force characteristics, and have been calibrated in accordance with Practice E74.
The procedures in Practices E4 may be used by those using, manufacturing, and providing calibration service for testing machines and related instrumentation.
SCOPE
1.1 These practices cover procedures for the force verification, by means of standard calibration devices, of tension or compression, or both, static or quasi-static testing machines (which may, or may not, have force-indicating systems). These practices are not intended to be complete purchase specifications for testing machines. Testing machines may be verified by one of the three following methods or combination thereof:
1.1.1 Use of standard weights,
1.1.2 Use of equal-arm balances and standard weights, or
1.1.3 Use of elastic calibration devices.
Note 1—These practices do not cover the verification of all types of testing machines designed to measure forces, for example, the constant-rate-of-loading type which operates on the inclined-plane principle. This type of machine may be verified as directed in the applicable appendix of Specification D76.  
1.2 The procedures of 1.1.1-1.1.3 apply to the verification of the force-indicating systems associated with the testing machine, such as a scale, dial, marked or unmarked recorder chart, digital display, etc. In all cases the buyer/owner/user must designate the force-indicating system(s) to be verified and included in the report.
1.3 The values stated in inch-pound units are to be regarded as standard. The values given in parentheses are mathematical conversions to SI units that are provided for information only and are not considered standard.
1.3.1 Since conversion factors are not required in this practice, either inch-pound units, SI units, or metric values can be used as the standard.
1.4 Forces indicated on displays/printouts of testing machine data systems—be they instantaneous, delayed, stored, or retransmitted—which are verified with provisions of 1.1.1, 1.1.2, or 1.1.3, and are within the ±1 % accuracy requirement, comply with Practices E4.
1.5 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use.

ABSTRACT
This practice defines a reference axis for each of the two principal types of rosette configurations and the equations used for three-element strain gage rosette data analysis. The primary uses of this analysis procedure are to determine the directions and magnitudes of the principal surface strains, and to determine residual stresses. This is important for consistency in reporting results and for avoiding ambiguity in data analysis, especially when computers are used. There are several possible sets of equations, but the set presented herein is perhaps the most common.
SCOPE
1.1 The two primary uses of three-element strain gage rosettes are (a) to determine the directions and magnitudes of the principal surface strains and (b) to determine residual stresses. Residual stresses are treated in a separate ASTM standard, Test Method E 837. This practice defines a reference axis for each of the two principal types of rosette configurations used and presents equations for data analysis. This is important for consistency in reporting results and for avoiding ambiguity in data analysis—especially when computers are used. There are several possible sets of equations, but the set presented here is perhaps the most common.

SIGNIFICANCE AND USE
Strain gauges are the most widely used devices for the determination of materials, properties and for analyzing stresses in structures. However, performance parameters of strain gauges are affected by both the materials from which they are made and their geometric design. These test methods detail the minimum information that must accompany strain gauges if they are to be used with acceptable accuracy of measurement.
Most performance parameters of strain gauges require mechanical testing that is destructive. Since test gauges cannot be used again, it is necessary to treat data statistically and then apply values to the remaining population from the same lot or batch. Failure to acknowledge the resulting uncertainties can have serious repercussions. Resistance measurement is non-destructive and can be made for each gauge.
Properly designed and manufactured strain gauges, whose properties have been accurately determined and with appropriate uncertainties applied, represent powerful measurement tools. They can determine small dimensional changes in structures with excellent accuracy, far beyond that of other known devices. It is important to recognize, however, that individual strain gauges cannot be calibrated. If calibration and traceability to a standard are required, strain gauges should not be employed.
To be used, strain gauges must be bonded to a structure. Good results depend heavily on the materials used to clean the bonding surface, to bond the gauge, and to provide a protective coating. Skill of the installer is another major factor in success. Finally, instrumentation systems must be carefully designed to assure that they do not unduly degrade the performance of the gauges. In many cases, it is impossible to achieve this goal. If so, allowance must be made when considering accuracy of data. Test conditions can, in some instances, be so severe that error signals from strain gauge systems far exceed those from the structural deformations to be measured....
SCOPE
1.1 The purpose of this standard is to provide uniform test methods for the determination of strain gauge performance characteristics. Suggested testing equipment designs are included.
1.2 Test Methods E 251 describes methods and procedures for determining five strain gauge parameters:
Section Part I—General Requirements 7 Part II—Resistance at a Reference Temperature 8 Part III—Gauge Factor at a Reference Temperature 9 Part IV—Temperature Coefficient of Gauge Factor10 Part V—Transverse Sensitivity11 Part VI—Thermal Output12
1.3 Strain gauges are very sensitive devices with essentially infinite resolution. Their response to strain, however, is low and great care must be exercised in their use. The performance characteristics identified by these test methods must be known to an acceptable accuracy to obtain meaningful results in field applications.
1.3.1 Strain gauge resistance is used to balance instrumentation circuits and to provide a reference value for measurements since all data are related to a change in the gauge resistance from a known reference value.
1.3.2 Gauge factor is the transfer function of a strain gauge. It relates resistance change in the gauge and strain to which it is subjected. Accuracy of strain gauge data can be no better than the precision of the gauge factor.
1.3.3 Changes in gauge factor as temperature varies also affect accuracy although to a much lesser degree since variations are usually small.
1.3.4 Transverse sensitivity is a measure of the strain gauge's response to strains perpendicular to its measurement axis. Although transverse sensitivity is usually much less than 10 % of the gauge factor, large errors can occur if the value is not known with reasonable precision.
1.3.5 Thermal output is the response of a strain gauge to temperature changes. Thermal output is an additive (not multiplicative) error. Therefore, it can often be much larger than the gauge output from stru...

SIGNIFICANCE AND USE
Methods and procedures used in installing bonded resistance strain gages can have significant effects upon the performance of those sensors. Optimum and reproducible detection of surface deformation requires appropriate and consistent surface preparation, mounting procedures, and verification techniques.
SCOPE
1.1 This guide provides guidelines for installing bonded resistance strain gages. It is not intended to be used for bulk or diffused semiconductor gages. This document pertains only to adhesively bonded strain gages.
1.2 The values stated in inch-pound units are to be regarded as standard. The values given in parentheses are mathematical conversions to SI units that are provided for information only and are not considered standard.
1.3 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use.

SIGNIFICANCE AND USE
Testing machines that apply and indicate force are used in many industries, in many ways. They may be used in a research laboratory to measure material properties, and in a production line to qualify a product for shipment. No matter what the end use of the machine may be, it is necessary for users to know the amount of force that is applied and indicated, and that the accuracy of the force is traceable to the National Institute of Standards and Technology (NIST), formerly NBS. Practices E 4 provides a procedure to verify these machines, in order that the indicated forces may be traceable. A key element to this NIST traceability is that the devices used in the verification have known force characteristics, and have been calibrated in accordance with Practice E 74.
The procedures in Practices E 4 may be used by those using, manufacturing, and providing calibration service for testing machines and related instrumentation.
SCOPE
1.1 These practices cover procedures for the force verification, by means of standard calibration devices, of tension or compression, or both, static or quasi-static testing machines (which may, or may not, have force-indicating systems). These practices are not intended to be complete purchase specifications for testing machines. Testing machines may be verified by one of the three following methods or combination thereof:
1.1.1 Use of standard weights,
1.1.2 Use of equal-arm balances and standard weights, or
1.1.3 Use of elastic calibration devices.
Note 1—These practices do not cover the verification of all types of testing machines designed to measure forces, for example, the constant-rate-of-loading type which operates on the inclined-plane principle. This type of machine may be verified as directed in the applicable appendix of Specification D 76.  
1.2 The procedures of 1.1.1-1.1.3 apply to the verification of the force-indicating systems associated with the testing machine, such as a scale, dial, marked or unmarked recorder chart, digital display, etc. In all cases the buyer/owner/user must designate the force-indicating system(s) to be verified and included in the report.
1.3 The values stated in inch-pound units are to be regarded as standard. The values given in parentheses are mathematical conversions to SI units that are provided for information only and are not considered standard.
1.3.1 Since conversion factors are not required in this practice, either inch-pound units, SI units, or metric values can be used as the standard.
1.4 Forces indicated on displays/printouts of testing machine data systems—be they instantaneous, delayed, stored, or retransmitted—which are verified with provisions of 1.1.1, 1.1.2, or 1.1.3, and are within the ±1 % accuracy requirement, comply with Practices E 4.
1.5 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use.