ASTM D3882-99
(Test Method)Standard Test Method for Bow and Skew in Woven and Knitted Fabrics
Standard Test Method for Bow and Skew in Woven and Knitted Fabrics
SCOPE
1.1 This test method covers the measurement of distortion of filling yarns in woven fabrics and courses in knitted fabrics from the normal path perpendicular to the fabric length. Note 1-For other references on imperfections refer to Fed. Std. No. 4b, Glossary of Fabric Imperfections; MIL STD 1491, Glossary of Knitting Imperfections; or MIL STD 655, Provisions for Evaluating Quality of Cloth, Wool and Wool Blends. Note 2-Other methods for the measurement of fabric construction characteristics include the following: D3773 Test Methods for Length of Woven Fabric D3774 Test Methods for Width of Woven Fabric D3775 Test Method for Fabric Count of Woven Fabric D3776 Test Methods for Mass per Unit Area (Weight) of Woven Fabric D3883 Test Method for Yarn Crimp or Yarn Takeup in Woven Fabrics
1.2 This test method can also be used to measure the distortion of printed geometric designs such as plaids.
1.3 This standard may involve hazardous materials, operations, and equipment. This standard does not purport to address all of the safety problems 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
Relations
Standards Content (Sample)
NOTICE: This standard has either been superseded and replaced by a new version or withdrawn.
Contact ASTM International (www.astm.org) for the latest information
Designation:D3882–99
Standard Test Method for
Bow and Skew in Woven and Knitted Fabrics
This standard is issued under the fixed designation D 3882; 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 3. Terminology
1.1 This test method covers the determination of bow and 3.1 Definitions:
skew of filling yarns in woven fabrics and the courses in 3.1.1 bow, n—afabricconditionresultingwhenfillingyarns
knitted fabrics. or knitting courses are displaced from a line perpendicular to
1.2 This test method can also be used to measure the bow the selvages and form one or more arcs across the width of the
and skew of printed geometric designs such as plaids. fabric. (See alsodouble bow .)
1.3 The values stated in either SI units or inch-pound units 3.1.2 double bow, n—two fabric bows, arcing in the same
are to be regarded separately as the standard. Within the text, direction, as in a flattened M or W depending on the viewing
the inch-pound units are shown in parentheses. The values angle. (See alsodouble bow .) (Compare double reverse bow.)
stated in each system may not be exact equivalents; therefore, 3.1.2.1 Discussion—In tubular knits, there may be differen-
each system shall be used independently of the other. Combin- tial bowing between the top and bottom of the tube.
ingvaluesfromthetwosystemsmayresultinnonconformance 3.1.3 double hooked bow, n—one hooked bow at each side
with this test method. of the fabric that arc in opposite directions. (See alsohooked
1.4 This standard does not purport to address all of the bow .)
safety concerns, if any, associated with its use. It is the 3.1.4 double reverse bow, n—two fabric bows arcing in
responsibility of the user of this standard to establish appro- opposite directions. (See also bowdouble bow.) (Compare .)
priate safety and health practices and determine the applica- 3.1.5 hooked bow, n—a fabric condition in which the filling
bility of regulatory limitations prior to use. yarns or knitted courses are in the proper position for most of
the fabric width but are pulled out of alignment at one side of
2. Referenced Documents
the fabric. (See also double hooked bow.)
2.1 ASTM Standards:
3.1.6 knitted fabric, n—astructureproducedbyinterlooping
D 123 Terminology Relating to Textiles
one or more ends of yarn or comparable materials.
D 1776 Practice for Conditioning Textiles for Testing 3.1.7 skew, n—a fabric condition resulting when filling
D 2904 Practice for Interlaboratory Testing of a Textile Test
yarns or knitted courses are angularly displaced from a line
Method that Produces Normally Distributed Data perpendicular to the edge or side of the fabric.
D 2906 Practice for Statements on Precision and Bias for
3.1.7.1 Discussion—Knitted courses or filling yarns usually
Textiles appear as straight line at right angles to the edge or side of the
D 3774 Test Method for Width of Woven Fabric
fabric.Whentubularknittedfabricisfinished,differentialskew
D 3990 Terminology Relating to Fabric Defects may occur on the top and bottom part of the tube.
2.2 AATCC Test Method:
3.1.8 standard atmosphere for testing textiles,
AATCC 179 Skewness Change in Fabric and Garment n—laboratoryconditionsfortestingfibers,yarns,andfabricsin
Twist Resulting from Automatic Home Laundering
which air temperature and relative humidity are maintained at
specific levels with established tolerances.
3.1.8.1 Discussion—Textile materials are used in a number
This test method is under the jurisdiction ofASTM Committee D13 onTextiles
ofspecificend-useapplicationsthatfrequentlyrequiredifferent
and is the direct responsibility of Subcommittee D13.60 on Fabrics, Specific.
testing temperatures and relative humidities. Specific condi-
Current edition approved April 10, 1999. Published July 1999. Originally
published as D 3882 – 80. Last previous edition D 3882 – 90. tioning and testing of textiles for end-product requirements can
For referenced ASTM standards, visit the ASTM website, www.astm.org, or
be carried out using Table 1 in Practice D 1776.
contact ASTM Customer Service at service@astm.org. For Annual Book of ASTM
3.1.9 For definitions of fabric defect terms, refer to Termi-
Standards volume information, refer to the standard’s Document Summary page on
nology D 3990. For definitions of other textile terms used in
the ASTM website.
Available from American Association of Textile Chemists and Colorists, P.O.
this test method, refer to Terminology D 123.
Box 12215, Research Triangle Park, NC 27709.
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.
D3882–99
TABLE 1 Critical Differences, 95% Probability Level, for Bow
colored, patterned fabrics such as plaids and horizontal stripes
and Skew for the Conditions Noted
rather than in solid colors because the contrast makes the
A
Property Number of Critical Differences for the Conditions Noted ,%
distortion more prominent. These defects may cause sewing
Observations in
Repeatability Reproducibility
problems in such fabrics and draping problems in finished
Each Average
products. In some cases, a specified amount of skew is needed,
(Within- (Between-
(Single-Operator)
Laboratory) Laboratory)
for example, to prevent trouser leg twisting. Matching plaids
Precision
Precision Precision
from distorted patterns may create serious problems for the
Bow 1 0.80 0.80 0.80
garment manufacturer or home sewer. Wavy or sharp breaks in
3 0.46 0.46 0.46
the bow line are more detrimental to the appearance of small
6 0.33 0.33 0.33
12 0.23 0.23 0.23
parts of a garment (such as collars, pockets, and so forth) than
24 0.16 0.16 0.16
a gradual slope from a straight line.
Skew 1 2.99 2.99 3.18
3 1.73 1.73 2.04
6. Apparatus
6 1.22 1.22 1.63
12 0.86 0.86 1.38 6.1 Measuring Stick or Steel Tape, graduated in 1-mm
24 0.61 0.61 1.24
( ⁄16-in.) divisions and longer than the width of the fabric that
A
The critical differences for Table 1 were calculated using t = 1.960, which is
is to be measured.
based on infinite degrees of freedom.
6.2 Rigid Straightedge, longer than the width of the fabric
that is to be measured.
6.3 Flat Surface, of sufficient length to unroll or unfold the
4. Summary of Test Method
fabric (see 6.4).
4.1 Bow—A straightedge is placed across the fabric be-
6.4 Fabric Inspection Table (Optional), to unroll and roll
tween two points at which a marked filling yarn, knitting
fabric rolls or unfold and fold fabric bolts with sufficient
course, designated printed line, or designated design meets the
lighting that provides transmitted light from underneath the
two selvages or edges. The greatest distance between the
fabric to make the defect more clearly visible.
straightedge and the marked filling line, knitting course,
designated printed line, or designated design is measured
7. Sampling and Test Specimens
parallel to the selvage.
4.2 Skew—The straight-line distortion of a marked filling
7.1 Primary Sampling Unit—Consider rolls or bolts of
yarn, knitting course, designated printed line, or designated
fabric or fabric components of fabricated systems to be the
design is measured from its normal perpendicular to the
primary sampling unit, as applicable.
selvage or edge.
7.2 Laboratory Sampling Unit—As a laboratory sampling
unit take the entire roll or bolt after removing a first 1-mm
5. Significance and Use
(1-yd)length.Forfabriccomponentsoffabricatedsystems,use
5.1 This test method is considered satisfactory for accep-
the entire system.
tance testing of commercial shipments.
7.3 Test Specimens—As test specimens, select 3 test areas
5.1.1 If there are differences of practical significance be-
from each laboratory sampling unit. Exclude the first and last
tween reported test results for two laboratories (or more),
fifth of the roll or bolt or piece length. Select test areas at
comparative tests should be performed to determine if there is
random but no closer to one another than one fifth of the roll
a statistical bias between them, using competent statistical
or bolt or piece length.
assistance. As a minimum, the test samples to be used are as
homogeneous as possible, are drawn from the material from
8. Conditioning
which the disparate test results were obtained, and are ran-
8.1 Conditionthetestspecimenstomoistureequilibriumfor
domlyassignedinequalnumberstoeachlaboratoryfortesting.
testing in the standard atmosphere for testing textiles in
Other fabrics with established test values may be used for this
accordance with Practice D 1776 or, if applicable, in the
purpose. The test results from the two laboratories should be
specified atmosphere in which the testing is to be performed.
compared using a statistical test for unpaired data, at a
8.1.1 When full rolls or bolts of fabric cannot be properly
probability level chosen prior to the testing series. If a bias is
conditioned in a reasonable time with available facilities,
found, either its cause must be found and corrected, or future
perform the test without conditioning and report the actual
test results must be adjusted in consideration of the known
condition prevailing at the time of the test. Such results may
bias.
not correspond with the results obtained when testing condi-
5.2 Individual rolls are normally accepted or rejected on the
tioned specimens at the standard atmosphere for testing tex-
basis of the maximum amount of bow or skew in a specific roll
tiles.
of fabric. The average bow or skew in a roll or lot or the range
of bow or skew in a roll may be determined but are not
9. Procedure
normally used in the trade for acceptance or rejection.
9.1 Test the test specimens in the standard atmosphere for
5.3 Bow or skew can be induced during fabric manufactur-
testing textiles in accordance with Section 8.
ing, dyeing, tentering, finishing, or other operations where a
potential exists for
...
Questions, Comments and Discussion
Ask us and Technical Secretary will try to provide an answer. You can facilitate discussion about the standard in here.