ASTM E4-21

Standard Practices for Force Calibration and Verification of Testing Machines

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...

General Information

• Status: Published
• Publication Date: 31-May-2021
• ICS: 19.060 - Mechanical testing
• Technical Committee: E28 - Mechanical Testing
• Drafting Committee: E28.01 - Calibration of Mechanical Testing Machines and Apparatus

Standards Content (Sample)

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.
Designation:E4 −21 American Association State
Highway and Transportation Officials Standards
AASHTO No: T67
Standard Practices for
1
Force Calibration and Verification of Testing Machines
This standard is issued under the fixed designation E4; the number immediately following the designation indicates the year of original
adoptionor,inthecaseofrevision,theyearoflastrevision.Anumberinparenthesesindicatestheyearoflastreapproval.Asuperscript
epsilon (´) indicates an editorial change since the last revision or reapproval.
This standard has been approved for use by agencies of the U.S. Department of Defense.
1. Scope* retransmitted—which are verified with provisions of 1.2.1,
1.2.2,or 1.2.3, and are within the specifications stated in
1.1 These practices cover procedures for the force calibra-
Section 15, comply with Practices E4.
tion and verification, by means of force measurement
standards, of tension or compression, or both, static or quasi- 1.6 The requirements of these practices limit the major
static testing machines (which may, or may not, have force- components of measurement uncertainty when calibrating
indicators). These practices are not intended to be complete testing machines. These Standard Practices do not require the
purchase specifications for testing machines. allowable force measurement error to be reduced by the
amount of the measurement uncertainty encountered during a
1.2 Testing machines may be verified by one of the three
calibration. As a result, a testing machine verified using these
following methods or combination thereof. Each of the meth-
practices may produce a deviation from the true force greater
ods require a specific measurement uncertainty, displaying
than 61.0 % when the force measurement error is combined
metrological traceability to The International System of Units
with the measurement uncertainty.
(SI).
1.7 This standard does not purport to address all of the
1.2.1 Use of standard weights,
safety concerns, if any, associated with its use. It is the
1.2.2 Use of equal-arm balances and standard weights, or
responsibility of the user of this standard to establish appro-
1.2.3 Use of elastic force measurement standards.
priate safety, health, and environmental practices and deter-
1.3 The procedures of 1.2.1–1.2.3 apply to the calibration
mine the applicability of regulatory limitations prior to use.
andverificationoftheforce-measuringsystemsassociatedwith
1.8 This international standard was developed in accor-
the testing machine, including the force indicators such as a
dance with internationally recognized principles on standard-
scale, dial, marked or unmarked recorder chart, digital display,
ization established in the Decision on Principles for the
etc. In all cases the buyer/owner/user must designate the
Development of International Standards, Guides and Recom-
force-measuring system(s) to be verified and included in the
mendations issued by the World Trade Organization Technical
certificate and report of calibration and verification.
Barriers to Trade (TBT) Committee.
1.4 Units—The values stated in either SI units or inch-
2. Referenced Documents
pound units are to be regarded separately as standard. The
2
values stated in each system are not necessarily exact equiva-
2.1 ASTM Standards:
lents; therefore, to ensure conformance with the standard, each
E6Terminology Relating to Methods of Mechanical Testing
system shall be used independently of the other, and values
E74Practices for Calibration and Verification for Force-
from the two systems shall not be combined.
Measuring Instruments
1.4.1 Other non-SI force units may be used with this
E467Practice for Verification of Constant Amplitude Dy-
standard such as the kilogram-force (kgf) which is often used
namic Forces in an Axial Fatigue Testing System
3
with hardness testing machines
2.2 BIPM Standard:
JCGM 100: Evaluation of measurement data - Guide to the
1.5 Forces indicated on displays/printouts of testing ma-
Expression of Uncertainty in Measurement.
chine data systems—be they instantaneous, delayed, stored, or
2
For referenced ASTM standards, visit the ASTM website, www.astm.org, or
1
These practices are under the jurisdiction of ASTM Committee E28 on contact ASTM Customer Service at [e-mail]. For Annual Book of ASTM
Mechanical Testing and is the direct responsibility of Subcommittee E28.01 on Standards volume information, refer to the standard’s Document Summary page on
Calibration of Mechanical Testing Machines and Apparatus. the ASTM website.
3
Current edition approved June 1, 2021. Published August 2021. Originally Available from BIPM - Pavillon de Breteuil F-92312 Sèvres Cedex FRANCE.
approved in 1923.
...

This document is not an ASTM standard and is intended only to provide the user of an ASTM standard an indication of what changes have been made to the previous version. Because
it may not be technically possible to adequately depict all changes accurately, ASTM recommends that users consult prior editions as appropriate. In all cases only the current version
of the standard as published by ASTM is to be considered the official document.
Designation: E4 − 20 E4 − 21 American Association State
Highway and Transportation Officials Standards
AASHTO No: T67
Standard Practices for
1
Force Calibration and Verification of Testing Machines
This standard is issued under the fixed designation E4; the number immediately following the designation indicates the year of original
adoption or, in the case of revision, the year of last revision. A number in parentheses indicates the year of last reapproval. A superscript
epsilon (´) indicates an editorial change since the last revision or reapproval.
This standard has been approved for use by agencies of the U.S. Department of Defense.
1. 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-indicating systems).
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 uncertainty of measurement, 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 force-measuring instruments.elastic force measurement standards.
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).
1.3 The procedures of 1.2.1–1.2.3 apply to the calibration and verification of the force-indicatingforce-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-indicatingforce-measuring system(s) to be verified and
included in the report.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 customarynon-SI force units may be used with this standard such as the kilogram-force (kgf) which is often used with
hardness testing machines
1
These practices are under the jurisdiction of ASTM Committee E28 on Mechanical Testing and is the direct responsibility of Subcommittee E28.01 on Calibration of
Mechanical Testing Machines and Apparatus.
Current edition approved Jan. 1, 2020June 1, 2021. Published March 2020August 2021. Originally approved in 1923. Last previous edition approved in 20162020 as
E4 – 16.E4 – 20. DOI: 10.1520/E0004-20.10.1520/E0004-21.
*A Summary of Changes section appears at the end of this standard
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States
1

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E4 − 21
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 61 % measurement accuracy
requirement,specifications stated in Section 15, comply with Practices E4.
1.6 The requirements of these practices limit the major components of measurement uncertainty when verifyingcalibrating 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 verification.calibration. As a result, a testing machine verified using these practices
may produce a deviation from the true force greater than 61.0 % when the force measurement error is combined with the
measurement uncertaintyuncertainty.
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 Prin
...