GB/T 14343-2008Testing method for linear density of man-made filament yarns (English PDF)

Foreword

Compared with BISFA standards "The testing method for polyester filament yarns" (2004), "The testing method for nylon filament yarns" (2004), and "The testing method for rayon, cupra, acetate, triacetate, and lyocell filament yarn" (1997), the consistency degree of linear density of this Standard is non-equivalent.

This Standard replaces GB/T 14343-2003 "Testing method for linear density of synthetic fiber filament yarns". Compared with GB 14343-2003, the main changes are as follows.

- MODIFY the scope of application; EXPAND it from synthetic filament to cellulose chemical fiber filament (see Chapter 1);

- MODIFY the sampling requirements, SAMPLE according to parts or bulk samples (see 4.3.1);

- INCREASE pre-controlled humidity temperature, relative humidity and time (see 4.3.21);

- MODIFY humidity and experimental standard atmospheric conditions and time (see 4.3.2.2);

- ADD the calculation of pre-tension load (see 4.3.3.1);

- ADD the half-width value of the confidence interval (± 1.5%) (see 4.3.5);

- ADD the test methods and calculations to the thread number determination of monofilament linear density and multifilament linear density;

- MODIFY the digital rounding of calculated results (see Chapter 7).

Appendix C of this Standard is normative; Appendix A and Appendix B are informative.

1 Scope

This Standard specifies the testing method for linear density of filament yarns (multifilament and monofilament) such as polyester (PET), polyamide (nylon), polypropylene (PP), and cellulose chemical fibers.

This Standard applies to the testing of linear density of filament yarns which are drawn from roll-packed or fabric. Strands and cables can refer to this Standard for implementation.

This Standard does not apply to the filament yarns of which the elongation is greater than 0.5% when the tension increases from 0.05 cN/dtex to 0.1 cN/dtex.

2 Normative references

The following normative documents contain provisions which, through reference in this text, constitute provisions of this Standard. For dated reference, all the subsequent amendments (excluding corrections) or revisions do not apply to this Standard, however, it is encouraged that the parties, who reach an agreement according to this Standard, study whether the latest versions of these documents can be used. For undated references, the latest editions of the normative documents referred to apply to this Standard.

GB/T 3291.3 Textiles - Terms of textile material properties and test - Part 3: General

GB/T 6502 Sampling method of man-made filament yarns

GB/T 6529 Textiles. Standard atmospheres for conditioning and testing

GB/T 8170 Rules of rounding off for numerical values

3 Terms and definitions

The following terms and definitions and those determined by GB/T 3291.3 apply to this Standard.

4 Test of multifilament yarn density

5 Linear density test of monofilament (determination of multifilament number)

6 Calculation results

6.1 The linear density is calculated according to formula (2).

6.2 The linear density of the monofilament is calculated according to the formula (3).

6.5 When conducting statistical analysis to each sample, SEE Appendix C.

7 Data rounding

All test results shall be rounded according to provisions of GB/T8170.Linear density, linear density deviation rate are rounded to one decimal place; variation coefficient is rounded to two decimal places.

8 Allowed errors

If needed, the manufacturers shall determine the allowed errors of linear density of batch products.

9 Test Report

Test report shall include.

Appendix A (Informative) Fast humidity method

A.1 This method specifies the time of sample fast humidity.

A.2 Under disputed circumstances, it shall only be adopted after being negotiated by the parties concerned. […]