ASTM D5034-95

NOTICE: This standard has either been superseded and replaced by a new version or discontinued.
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Designation: D 5034 – 95
Standard Test Method for
Breaking Strength and Elongation of Textile Fabrics (Grab
Test)
This standard is issued under the fixed designation D 5034; 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.
1. Scope D 1776 Practice for Conditioning Textiles for Testing
D 5035 Test Method for Breaking Force and Elongation of
1.1 This test method covers the grab and modified grab test
Textile Fabrics (Strip Force)
procedures for determining the breaking strength and elonga-
tion of most textile fabrics. Provisions are made for wet testing.
3. Terminology
1.1.1 The grab test procedure is applicable to woven,
3.1 Definitions:
nonwoven, and felted fabrics, while the modified grab test
3.1.1 breaking force, n—the maximum force applied to a
procedure is used primarily for woven fabrics.
material carried to rupture. (Compare breaking point, breaking
1.2 This test method is not recommended for glass fabrics,
strength. Syn. force-at-break.)
or for knitted fabrics and other textile fabrics which have high
3.1.1.1 Discussion—Materials that are brittle usually rup-
stretch (more than 11 %).
ture at the maximum force. Materials that are ductile usually
NOTE 1—For the determination of the breaking force and elongation of
experience a maximum force before rupturing.
textile fabrics using the raveled strip test procedure and the cut strip test
3.1.2 breaking load, n—deprecated term. Use breaking
procedure, refer to Test Method D 5035.
force.
1.3 This test method provides the values in both inch-pound
3.1.3 constant-rate-of-extension (CRE) tensile testing
units and SI units. Inch-pound units is the technically correct
machine—a testing machine in which the rate of increase of
name for the customary units used in the United States. SI units
specimen length is uniform with time.
is the technically correct name for the system of metric units
3.1.4 constant-rate-of-load (CRL) tensile testing
known as the International System of Units. The values stated
machine—a testing machine in which the rate of increase of the
in either acceptable metric units or in other units shall be
load being applied to the specimen is uniform with time after
regarded separately as standard. The values stated in each
the first 3 s.
system may not be exact equivalents; therefore, each system
3.1.5 constant-rate-of-traverse (CRT) tensile testing
must be used independently of the other, without combining in
machine—a testing machine in which the pulling clamp moves
any way.
at a uniform rate and the load is applied through the other
1.4 This standard does not purport to address all of the
clamp which moves appreciably to actuate a weighing mecha-
safety concerns, if any, associated with its use. It is the
nism, so that the rate of increase of load or elongation is
responsibility of the user of this standard to establish appro-
dependent upon the extension characteristics of the specimen.
priate safety and health practices and determine the applica-
3.1.6 elongation, n—the ratio of the extension of a material
bility of regulatory limitations prior to use.
to the length of the material prior to stretching, expressed as a
percent.
2. Referenced Documents
3.1.7 extension, n—the change in length of a material due to
2.1 ASTM Standards:
stretching. (Compare elongation.)
D 76 Specification for Tensile Testing Machines for Tex-
3.1.8 grab test, n—in fabric testing, a tensile test in which
tiles
the central part of the width of the specimen is gripped in the
D 123 Terminology Relating to Textiles
clamps.
D 629 Test Methods for Quantitative Analysis of Textiles
3.1.8.1 Discussion—For example, if the specimen width is
D 1059 Test Method for Yarn Number on Short-Length
100 mm (4.0 in.), and the width of the jaw faces 25 mm (1.0
Specimens
in.), the specimen is gripped in the clamp with approximately
37.5 mm (1.5 in.) of fabric protruding from each side of the
jaws.
This test method is under the jurisdiction of ASTM Committee D-13 on Textiles
3.1.9 modified grab test, n—in fabric testing, a tensile test in
and is the direct responsibility of Subcommittee D13.60 on Fabric Test Methods,
which the control part of the width of the specimen is gripped
Specific.
Current edition approved May 15, 1995. Published July 1995. Replaces Grab
Testing sections of Test Method D 1682 – 90.
2 3
Annual Book of ASTM Standards, Vol 07.01. Annual Book of ASTM Standards, Vol 07.02.
Copyright © ASTM, 100 Barr Harbor Drive, West Conshohocken, PA 19428-2959, United States.
D 5034
in the clamps and in which lateral slits are made midlength of of commercial shipments of most woven textile fabrics, since
the specimen severing all yarns bordering that portion of the the procedures have been used extensively in the trade for
specimen held between the two clamps. acceptance testing.
3.1.9.1 Discussion—The slot modification reduces the fab- 5.1.1 In case of disagreement arising from differences in
ric assistance inherent in the grab test procedure to a practical reported test values when using this test method for acceptance
minimum (see Fig. 1). testing of commercial shipments, the purchaser and the sup-
3.1.10 tensile test, n—in textiles, a test in which a textile plier should conduct comparative tests to determine if there is
material is stretched in one direction to determine the load- a statistical bias between their laboratories. Competent statis-
elongation characteristics, the breaking load, or the breaking tical assistance is recommended for the investigation of bias.
elongation. As a minimum, the two parties should take a group of test
3.1.11 For definitions of other terms used in this test specimens which are as homogeneous as possible and which
method, refer to Terminology D 123. are from a lot of material of the type in question. The test
specimens should then be randomly assigned in equal numbers
4. Summary of Test Method
to each laboratory for testing. The average results from the two
4.1 A 100-mm (4.0-in.) wide specimen is mounted centrally laboratories should be compared using Student’s t-test for
in clamps of a tensile testing machine and a force applied until unpaired data and an acceptable probability level chosen by the
the specimen breaks. Values for the breaking force and the two parties before testing is begun. If a bias is found, either its
elongation of the test specimen are obtained from machine cause must be found and corrected, or the purchaser and the
scales, dials, autographic recording charts, or a computer supplier must agree to interpret future test results in light of the
known bias.
interfaced with the testing machine.
4.2 This test method describes procedures for carrying out 5.2 This test method is not recommended for knitted fabrics
because of their high stretch.
fabric grab tensile tests using two types of specimens and three
alternative types of testing machines. For reporting, use the 5.3 Some modification of technique may be necessary for
any fabric having a strength in excess of 200-N/cm (1140-lb/
following identification system of specific specimen and ma-
chine combinations. in.) width. Special precautionary measures are provided for use
when necessary for strong fabrics.
4.2.1 Type of specimen:
4.2.1.1 G—Grab 5.4 All of the procedures are applicable for testing fabrics
4.2.1.2 MG—Modified grab either conditioned or wet.
4.2.2 Type of tensile testing machine: 5.5 Comparison of results from tensile testing machines
4.2.2.1 E—Constant-rate-of-extension (CRE) operating on different principles is not recommended. When
4.2.2.2 L—Constant-rate-of-load (CRL) different types of machines are used for comparison testing,
4.2.2.3 T—Constant-rate-of -traverse (CRT) constant-time-to-break at 20 6 3 s is the established way of
4.2.3 Possible combinations can be identified as follows: producing data. Even then the data may differ significantly.
5.6 Although a constant-rate-of-extension is preferred in
Type of Tester
Constant-Rate- Constant-Rate- Constant-Rate-
these procedures, in cases of dispute, unless there is agreement
Test Specimen of-Extension of-Load of-Traverse
to the contrary between the purchaser and the supplier, a
Grab G-E G-L G-T
Modified Grab MG-E MG-L MG-T constant-time-to-break (20 6 3 s) is to be used.
For example, Test Method D 5034, G-E refers to a grab test carried out on a
5.7 The grab test procedure is applicable to the determina-
constant rate-of-extension tensile testing machine.
tion of the effective strength of the fabric; that is, the strength
of the yarns in a specific width together with the fabric
5. Significance and Use
assistance from the adjacent yarns. The breaking force deter-
5.1 The grab test procedure in this test method for the
mined by the grab procedure is not a reflection of the strength
determination of breaking force and elongation is considered
of the yarns actually gripped between clamps and cannot be
satisfactory for acceptance testing of commercial shipments of
used for direct comparison with yarn strength determinations.
most woven or nonwoven textile fabrics, and the modified grab
Grab test specimens require much less time to prepare although
test procedure is considered satisfactory for acceptance testing
they require more fabric per specimen. There is no simple
relationship between grab tests and strip tests since the amount
of fabric assistance depends on the type of fabric and construc-
tion variables.
5.8 The modified grab test procedure is applicable to the
determination of the breaking force of fabrics with construc-
tions in which the application of tensile stress on raveled strip
specimens produces further unraveling. This test method is
particularly applicable to high-strength fabrics.
6. Apparatus, Reagents, and Materials
Metric Equivalents
in. 4 8 to 10 6.1 Tensile Testing Machine, of the CRE, CRL, or CRT type
mm 100 200 to 250
conforming to Specification D 76, with respect to force indi-
FIG. 1 Illustration of Modified Grab Test Specimens cation, working range, capacity, and elongation indicator, and
D 5034
7. Sampling
7.1 Lot Sample—Take a lot sample as directed in the
applicable material specification. In the absence of such a
specification, randomly take rolls or pieces that constitute the
lot sample using the following schedule:
Number of Rolls, Pieces in Lot, Number of Rolls or Pieces in Lot
Inclusive Sample
1to3 all
4to24 4
25 to 50 5
over 50 10 % to a maximum of 10 rolls or
pieces
NOTE 3—An adequate specification or other agreement between the
purchaser and the supplier requires taking into account the variability
Metric Equivalents
between rolls of fabric and between specimens from a swatch from a roll
of fabric to provide a sampling plan with a meaningful producer’s risk,
in. 1 2
consumer’s risk, acceptable quality level, and limiting quality level.
mm 25 50
FIG. 2 Schematic Illustration of Jaw Faces for Modified Grab Test
7.2 Laboratory Sample—From each roll or piece of fabric
taken from the lot sample, cut at least one laboratory sample
designed for operation at a speed of 300 6 10 mm/min (12 6
the full width of the fabric and1m(1yd) along the selvage
0.5 in./min); or, a variable speed drive, change gears, or (machine direction).
interchangeable weights as required to obtain the 20 6 3-s
NOTE 4—Results obtained on small hand samples (swatches) can only
time-to-break (see 5.5 and 5.6).
be considered as representative of the sample swatch and cannot be
6.2 Clamps and Jaw Faces—Each jaw face shall be smooth,
assumed to be representative of the fabric piece from which the hand
flat, and with a metallic, or other agreed upon, gripping surface.
sample (swatch) was taken.
The faces shall be parallel and have matching centers with
7.3 Test Specimens—From each laboratory sample, take five
respect to one another in the same clamp and to the corre-
specimens from the warp (machine) direction and eight speci-
sponding jaw face of the other clamp.
mens from the filling (cross) direction (if tested) for each
6.2.1 For grab tests, each clamp shall have a front (or top)
testing condition.
jaw face measuring 25 6 1 mm (1.0 6 0.02 in.) perpendicular
7.3.1 Testing conditions include the following:
to the direction of the application of the force, and not less than
7.3.1.1 Warp or Machine Direction—Standard conditions
25 nor more than 50 mm (1.0 nor more than 2.0 in.) parallel to
for testing textiles.
the direction of the application of the force (Note 2). The back,
7.3.1.2 Warp or Machine Direction—Wet at 21°C (70°F).
or bottom, jaw face of each clamp shall be at least as large as
7.3.1.3 Filling or Cross Direction—Standard conditions for
its mate. Use of a larger face for the second jaw reduces the
testing textiles.
problem of front and back jaw face misalignment.
7.3.1.4 Filling or Cross Direction—Wet at 21°C (70°F).
NOTE 2—Front (or top) faces measuring 25 by 50 mm (1.0 by 2.0 in.)
7.3.2 When using the constant-time-to-break technique and
will not necessarily give the same value as 25 by 25-mm (1.0 by 1.0-in.)
unfamiliar fabrics, prepare two or three extra specimens to
faces. For many materials, the former are preferable because of the larger
establish the proper rate of loading (or speed for testing).
gripping area which tends to reduce slippage. While both sizes of gripping
surface are permitted, the face sizes used must be the same for all samples
8. Conditioning
in the test and must be recorded in the report.
8.1 For Conditioned Testing:
6.2.2 For modified grab tests, the top (or front) jaw faces
8.1.1 If the samples have a higher moisture content than the
shall measure 25 by 50 mm (1.0 by 2.0 in.) or more, with the
moisture present when at equilibrium in the standard atmo-
longer dimension parallel to the direction of load application.
sphere for testing textiles, precondition as directed in Practice
The bottom (or back) jaw faces shall measure 50 by 50 mm
D 1776.
(2.0 by 2.0 in.) or more. (See Fig. 2.)
8.1.2 Bring samples to moisture equilibrium in the standard
6.3 Metal Clamp, auxiliary, 170 g (6 oz) with at least
atmosphere for testing textiles as directed in Practice D 1776.
100-mm (4.0-in.) width anvils.
Equilibrium is considered to have been reached when the
6.4 Distilled Water, for wet testing.
increase in mass of the specimen in successive weighings made
6.5 Nonionic Wetting Agent, for wet testing.
at intervals of not less than 2 h does not exceed 0.1 % of the
6.6 Container, for wetting out specimens.
mass of the specimen.
6.7 Standard Fabrics, for use in verification of ap
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