Standard Practice for Verification and Classification of Extensometer

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 gages directly bonded to a specimen cannot be calibrated or verified with the apparatus described in this practice for the verification of extensometers having definite gage 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.

General Information

Status
Historical
Publication Date
09-Dec-2000
Current Stage
Ref Project

Relations

Buy Standard

Standard
ASTM E83-00e1 - Standard Practice for Verification and Classification of Extensometer
English language
12 pages
sale 15% off
Preview
sale 15% off
Preview

Standards Content (Sample)

An American National Standard
e1
Designation: E 83 – 00
Standard Practice for
1
Verification and Classification of Extensometer System
This standard is issued under the fixed designation E 83; 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 (e) indicates an editorial change since the last revision or reapproval.
This standard has been approved for use by agencies of the Department of Defense.
1
e NOTE—The Word “System” was added editorially to the title in November 2001.
1. Scope 3.1.2 calibration factor—the factor by which the change in
extensometer reading must be multiplied to obtain the equiva-
1.1 This practice covers procedures for the verification and
lent strain.
classification of extensometer systems, but it is not intended to
3.1.2.1 Discussion—For any extensometer, the calibration
be a complete purchase specification. The practice is applicable
factor is equal to the ratio of change in length to the product of
only to instruments that indicate or record values that are
the gage length and the change in the extensometer reading.
proportional to changes in length corresponding to either
For direct-reading extensometers the calibration factor is unity.
tensile or compressive strain. Extensometer systems are clas-
3.1.3 compressometer—a specialized extensometer used for
sified on the basis of the magnitude of their errors.
sensing negative or compressive strain.
1.2 Because strain is a dimensionless quantity, this docu-
3.1.4 deflectometer—a specialized extensometer used for
ment can be used for extensometers based on either SI or US
sensing of extension or motion, usually without reference to a
customary units of displacement.
specific gage length.
NOTE 1—Bonded resistance strain gages directly bonded to a specimen
3.1.5 error, in extensometer systems—the value obtained by
cannot be calibrated or verified with the apparatus described in this
subtracting the correct value of the strain from the indicated
practice for the verification of extensometers having definite gage points.
value given by the extensometer system.
(See procedures as described in Test Methods E 251.)
3.1.6 extensometer—a device for sensing strain. An exten-
1.3 This standard does not purport to address all of the
someter may be one of two types:
safety concerns, if any, associated with its use. It is the
3.1.7 Self-contained type.
responsibility of the user of this standard to establish appro-
3.1.8 Non-self-contained type (that requires an auxiliary
priate safety and health practices and determine the applica-
device (for example, recorder, digital readout, computer dis-
bility of regulatory limitations prior to use.
play, etc.)) for readout of strain values.
3.1.8.1 Discussion—For some extensometers the gage
2. Referenced Documents
length is fixed, while for others the gage length is variable and
2.1 ASTM Standards:
must be set or determined before the linear strain can be
E 6 Terminology Relating to Methods of Mechanical Test-
calculated.
2
ing
3.1.9 extensometer systems—a system for sensing and
E 21 Test Methods for Elevated Temperature Tension Tests
indicating strain.
2
of Metallic Materials
3.1.9.1 Discussion—The system may be an extensometer of
E 251 Test Methods for Performance Characteristics of
the self-contained type or the combination of an extensometer
2
Metallic Bonded Resistance Strain Gages
of the non-self-contained transducer type with a suitable
readout device.
3. Terminology
3.1.10 resolution of the strain indicator—the smallest
3.1 Definitions: In addition to the terms listed, see Termi-
change in strain that can be estimated or ascertained on the
nology E 6.
strain indicating apparatus of the testing system, at any applied
3.1.1 calibration—a determination of the calibration factor
strain.
for a system using established procedures.
3.1.11 resolution of analog type indicator (dials, recorders,
and so forth)—the strain represented by one graduation mul-
1
This practice is under the jurisdiction of ASTM Committee E28 on Mechanical
tiplied by the ratio of the width of the pointer or pen line to the
Testing and is the direct responsibility of Subcommittee E28.01 on Calibration of
center distance between two adjacent graduation marks. The
Mechanical Testing Machines and Apparatus.
typical ratios used are 1:1, 1:2, 1:5, or 1:10. A spacing of 0.10
Current edition approved Dec. 10, 2000. Published February 2001. Originally
published as E 83 – 50. Last previous edition E 83 – 98.
in. (2.5 mm) or greater is recommended for a resolution equal
2
Annual Book of ASTM Standards, Vol 03.01.
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.
1

---------------------- Page: 1 ----------------------
E83
to the strain represented by 1:10 of a graduation. A ratio less 5. Verification Procedure for E
...

Questions, Comments and Discussion

Ask us and Technical Secretary will try to provide an answer. You can facilitate discussion about the standard in here.