Standard Test Method for Grading Spun Yarns for Appearance

SCOPE
1.1 This test method covers the grading of singles spun yarns for appearance.  
1.2 This test method does not apply to plied yarns.  
1.3 This standard does not purport to address 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.

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Publication Date
31-Dec-1995
Technical Committee
Drafting Committee
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ASTM D2255-96 - Standard Test Method for Grading Spun Yarns for Appearance
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NOTICE: This standard has either been superseded and replaced by a new version or discontinued.
Contact ASTM International (www.astm.org) for the latest information.
Designation: D 2255 – 96
Standard Test Method for
Grading Spun Yarns for Appearance
This standard is issued under the fixed designation D 2255; 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.
INTRODUCTION
Cotton yarn appearance standards were first adopted in 1938 and revised in 1964, with Series III
being revised again in 1975. The 1964 boards had different yarn sizes for the four-grade exhibits on
each board. The 1975 Series III board used the same yarn number for each grade.
The appearance grade of yarn is based on the composite evaluation of several factors, such as
unevenness, fuzziness, and neppiness. The differences in the yarn numbers in the 1964 standards along
with the differences in other factors distort the comparison between grades and makes grading more
difficult.
To overcome this shortcoming, in 1975 the Series III board was revised using the same size yarn
for all four grades. After evaluating the improvements, it was decided to revise all of the series using
a mid-range yarn number for each grade in the series, and narrow the range in the most active series.
This was accomplished by adding a new board, Series VI. A near mid-range yarn number was selected
to represent equal steps between adjacent grades for all the factors considered in yarn appearance
grading. These yarns were produced with current commercial manufacturing equipment and practices.
Finally, to obtain better yarn definition and better reproducibility from set to set, it was decided to
use offset photo printing.
Shortly after these new boards were published in 1979, it became apparent that in the Series II-79
Board the A and B grades were not clearly defined and appeared to be switched. This was corrected
in the 1987 Series II Board.
In 1987 a world wide survey was conducted on how the Yarn Appearance Boards were being used.
From responses it became apparent that the boards are being used for grading yarns other than 100 %
cotton combed or carded yarns. Respondents were using the boards to grade yarn blends, ring spun
yarns, open-end spun yarns and other spinning systems. The boards are used both for process quality
control and customer acceptance.
In view of the above findings, it was decided to revise the method to include grading of all single
spun yarns.
1. Scope 2. Referenced Documents
1.1 This test method covers the grading of singles spun 2.1 ASTM Standards:
yarns for appearance. D 123 Terminology Relating to Textiles
1.2 This test method does not apply to plied yarns. D 2258 Practice for Sampling Yarn for Testing
1.3 This standard does not purport to address the safety
3. Terminology
problems associated with its use. It is the responsibility of the
3.1 Definitions:
user of this standard to establish appropriate safety and health
practices and determine the applicability of regulatory limita- 3.1.1 bunch, n—a defect in a yarn characterized by a
2 1
segment not over 6 mm ( ⁄4 in.) in length that shows an abrupt
tions prior to use.
increase in diameter caused by more fibers matted in this
particular place.
3.1.2 cover, n—in yarns, the outside layer of fibers that form
This test method is under the jurisdiction of ASTM Committee D-13 on Textiles
the surface of a yarn.
and is the direct responsibility of Subcommittee D13.58 on Yarn Test Methods,
3.1.3 fuzz, n—untangled fiber ends that protrude from the
General.
surface of a yarn or fabric.
Current edition approved April 10, 1996. Published June 1996. Originally
published as D 2255 – 64. Last previous edition D 2255 – 90.
The requirements for the appearance of cotton yarns are covered in Tolerances
D2645, Roller-Drafted Yarns. 3
Annual Book of ASTM Standards, Vol 07.01.
Copyright © ASTM, 100 Barr Harbor Drive, West Conshohocken, PA 19428-2959, United States.
NOTICE: This standard has either been superseded and replaced by a new version or discontinued.
Contact ASTM International (www.astm.org) for the latest information.
D 2255
TABLE 1 Requirements for Preparations of Specimens
3.1.3.1 Discussion—Fuzz should not be confused with
B
“cover.” Range of Yarn Numbers Wraps
A
Series Count
3.1.4 nep, n—a tightly tangled knot-like mass of unorga-
Single Cot-
Tex per in. per cm
ton Count
nized fibers. (Compare nap, pill.)
3.1.5 slub, n—an abuptly thickened place in a yarn. (Syn. 1 1 to 12 590 to 50 + 8 20 8
2 12+to 24 50to 25+ 18 22 9
lump, piecing, slough-off, slug. Compare cockles.)
3 24+to 36 25to 16+ 30 26 10
3.1.6 thick place, n—a yarn defect characterized by a
4 36+to 50 16to 12+ 42 32 13
5 50+to 75 12to 8+ 60 38 15
diameter greater than that of the adjoining segments and
6 75 + to 135 8 to 4 + 100 48 19
extending for 6 mm ( ⁄4 in.).
A
Actual single yarn count used on boards.
3.1.6.1 Discussion—The thick place is normally caused by
B
The specified number of wraps is subject to a tolerance of 6 10 %.
a greater number of fibers per yarn cross section than usual.
3.1.7 thin place, n—a yarn defect characterized by a seg-
6. Significance and Use
ment that is at least 25 % smaller in diameter than the average
diameter of the yarn. 6.1 This method is considered satisfactory for acceptance
3.1.7.1 Discussion—A thin place may be of any length. grading of commercial shipments because it has been used
extensively in the trade for this purpose.
3.1.8 yarn appearance, n—the visual effect obtained by
viewing a sample of yarn wound with a designated traverse on 6.1.1 In case of dispute, the statistical bias, if any, between
the laboratory of the purchaser and the laboratory of the
a black board of designated size.
supplier should be determined with each comparison being
3.1.9 For definitions of other textile terms used in this
based on testing randomized specimens from one sample of
method, refer to Terminology D 123.
material.
4. Description of Yarn Grades 6.2 The appearance of a woven or knitted fabric depends to
a large extent on the smoothness, cleanliness, and general
4.1 Grade A Yarn—Grade A yarn may have no large neps
appearance of the yarns from which the fabric is manufactured.
which are over three times the normal diameter of the yarn and
Instruments are available for the measurement of unevenness
very few small ones. Grade A yarn must have good uniformity
and for counting neps and other imperfections in yarn, but the
from inch to inch, and good cover without excessive fuzziness.
values obtained from such tests are not easily integrated into an
No foreign matter may be present in Grade A yarn.
over-all expression for actual fabric appearance. Yarn appear-
4.2 Grade B Yarn—Grade B Yarn may have no large neps,
ance grading affords additional information which the manu-
but may have a few small ones. Grade B yarn may have no
facturer of woven or knitted goods may, through experience,
more than three small pieces of foreign matter per board or
correlate with the appearance to be expected in fabrics made
specimen providing they do not form slubs. Grade B yarn may
from the yarns.
be slightly more irregular and may have slightly more fuzz than
a Grade A yarn.
7. Apparatus
4.3 Grade C Yarn—Grade C yarn may have more neps, and
7.1 Spun Yarn Appearance Standards —A series of photo-
larger ones as well as more fuzziness and a greater amount of
graphic standards representing Grades A, B, C, and D in six
foreign matter than Grade B yarn. The contrast between the
ranges of yarn numbers. Grade A is the highest and the others
thick and thin places and the normal diameter of the yarn may
are progressively lower. The range of yarn numbers to be
be greater than in Grade B yarn resulting in an over-all rougher
graded by each series is listed in Table 1. The standards are
appearance.
illustrated in Fig. 1.
4.4 Grade D Yarn—Grade D yarn may have some slubs that
7.2 Yarn Grading Cabinet —A cabinet with storage space
are more than three times the average diameter of the yarn.
for the appearance standards, a shelf or rack on which one
Grade D yarn may have more neps, neps of a larger size, more
panel of standards and the specimen to be graded can be
thick and thin places, more fuzz and more foreign matter than
displayed, and lights mounted on brackets to illuminate the
Grade C yarn. When slubs or large neps are present, Grade D
specimen and standards at the proper angle. A picture of the
yarn may have fewer neps than Grade C yarn. Grade D yarn
yarn appearance grading cabinet being used by a grader is
may have an over-all rougher appearance than Grade C yarn.
shown in Fig. 2.
4.5 Yarn Below Grade D—Yarn below Grade D may have
7.2.1 The lights on the cabinet shall consist of two units
more defects and an overall rougher appearance than Grade D
focused on the standard when in the grading position from a
yarn.
location about 300 mm (12 in.) in front with one unit slightly
NOTE 1—The permitted number of defects for any grade should always
above and one unit slightly below the standards. Each unit shall
be determined by comparison with the official “ASTM Spun Yarn
be equipped with two 150-W daylight incandescent bulbs
Appearance Standards” photographs.
5. Summary of Test Method
Available from the ASTM Headquarters. Request adjunct No. as follows:
ADJD225501 (Series 1-79) ADJD225504 (Series 4-79)
5.1 Yarn specimens, wound on black boards, are compared
ADJD225502 (Series 2-79) ADJD225505 (Series 5-79)
with photographs of specimens representing the appearance
ADJD225503 (Series 3-79) ADJD225506 (Series 6-79)
grades. The grade is based on fuzziness, neppiness, uneven-
Prints of detailed drawings of a suitable cabinet are available fr
...

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