ASTM D861-01

Standard Practice for Use of the Tex System to Designate Linear Density of Fibers, Yarn Intermediates, and Yarns

SCOPE
1.1 This practice covers the use of the tex system to designate the linear density (number, or count) of fibers and of yarns made from any type of fiber or combination of fibers. It is also applicable to other textile materials, including yarn intermediates (slivers, rovings, tops, etc.), single or plied yarns, cords, and threads.
Note 1—The mass per unit length concept of linear density is applicable to any material which has a high ratio of length to cross section.
1.2 Conversion factors for various indirect and direct yarn numbers to exact tex equivalents can be found in Standard Tables D 2260.
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-Sep-2001
• ICS: 59.080.20 - Yarns
• Technical Committee: D13 - Textiles
• Drafting Committee: D13.58 - Yarns and Fibers

Relations

• Replaces: ASTM D861-95 - Standard Practice for Use of the Tex System to Designate Linear Density of Fibers, Yarn Intermediates, and Yarns
• Effective Date: 10-Sep-2001
• Replaced By: ASTM D861-01a - Standard Practice for Use of the Tex System to Designate Linear Density of Fibers, Yarn Intermediates, and Yarns
• Effective Date: 10-Sep-2001
• Referred By: ASTM E337-15(2023) - Standard Test Method for Measuring Humidity with a Psychrometer (the Measurement of Wet- and Dry-Bulb Temperatures)
• Effective Date: 10-Sep-2001
• Referred By: ASTM D4849-21 - Standard Terminology Related to Yarns and Fibers
• Effective Date: 10-Sep-2001
• Referred By: ASTM D1244-98(2020) - Standard Practice for Designation of Yarn Construction
• Effective Date: 10-Sep-2001

Standards Content (Sample)

NOTICE: This standard has either been superseded and replaced by a new version or discontinued.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 861 – 01
Standard Practice for
Use of the Tex System to Designate Linear Density of
1
Fibers, Yarn Intermediates, and Yarns
This standard is issued under the fixed designation D 861; 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.
4
1. Scope Guide to Metrication for the Textile Industry
1.1 This practice covers the use of the tex system to
3. Terminology
designate the linear density (number, or count) of fibers and of
3.1 Definitions:
yarns made from any type of fiber or combination of fibers. It
3.1.1 linear density, n.—mass per unit length.
is also applicable to other textile materials, including yarn
3.1.1.1 Discussion—It is common practice to determine the
intermediates (slivers, rovings, tops, etc.), single or plied yarns,
“mass” of objects on beam balances or scales and call the result
cords, and threads.
the “weight” of the object instead of the technically correct
NOTE 1—The mass per unit length concept of linear density is appli-
term “mass” used in the definitions of “tex,” and “linear
cable to any material which has a high ratio of length to cross section.
density.”
1.2 Conversion factors for various indirect and direct yarn
3.1.2 tex, n.—the unit of linear density equal to the mass in
numbers to exact tex equivalents can be found in Standard
grams of 1000 m of fiber, yarn, or other textile strand, that is
Tables D 2260.
used in a direct yarn numbering system.
1.3 This standard does not purport to address all of the
3.1.2.1 Discussion—The terms kilotex, decitex, and millitex
safety concerns, if any, associated with its use. It is the
are frequently used to express linear density. Conversion
responsibility of the user of this standard to establish appro-
factors from tex to these measures are contained in Tables D
priate safety and health practices and determine the applica-
2260.
bility of regulatory limitations prior to use.
3.1.3 For definitions of other textile terms used in this
practice, refer to Terminology D 123.
2. Referenced Documents
4. Significance and Use
2.1 ASTM Standards:
2
D 123 Terminology Relating to Textiles
4.1 The tex system has been approved for general use by the
D 2260 Tables of Conversion Factors and Equivalent Yarn
International Organization for Standardization, Technical
2
Numbers Measured in Various Numbering Systems
Committee 38 on Textiles (ISO/TC 38), which has also
2.2 ISO Standards:
recommended a list of rounded tex numbers for use with fibers
ISO 1144 Textiles—Universal System for Designating Lin-
and all types of yarns. Conversion tables showing the rounded
3
ear Density (Tex System)
tex numbers corresponding to various numbers in different
ISO 2947 Textiles—Integrated Conversion Table for Re-
traditional systems are given in Tables D 2260 and ISO 2947.
placing Traditional Yarn Numbers by Rounded Values in
4.2 The tex system for designation of the linear density of
3
the Tex System
fibers and yarns is a direct system based on mass per unit
2.3 Other Document:
length, M/L, and employs metric units of length and mass. The
tex unit, grams per kilometre (1000 m) has been approved by
ISO/TC 38 for use with all fibers and all types of yarn. The
committee has also approved the use of kilotex and decatex
1 numbers for coarse structures
...