GB/T 6500-2008Test method for moisture regain of hair fibers -- Oven method (English PDF)

Foreword

This standard IWTO-33-98 "scoured or carbonized wool absolute dry weight and invoice calculation to determine the weight," the degree of non-conformity Equivalent.

This standard replaces GB/T 6500-1986 "Test method for moisture regain wool oven method." this standard and GB/T 6500-1986 compared to the main changes are as follows.

--- The scope of the original standard of scoured wool and wool tops expanded to pile fibers (version 1986 Scope; Chapter 1 of this edition).

--- Original standard periodic sampling to random sampling method (version 5.1.2 1986; this edition 7.2).

--- Increased in Chapter 3 of the English term (Chapter 3 of this edition).

--- Original standard a uniform mass of the sample to a predetermined quality samples were different depending on the type of pile fibers (1986 Version 5.3; 8.1 edition).

--- Regain adjusted depending on the initial weighing time (this version 8.3.3).

--- Increased depending on the environment of the detection result correcting content (edition of Appendix A).

Appendix A of this standard is a normative appendix.

This standard is proposed and managed by China Fiber Inspection Bureau.

This standard was drafted. Fiber Inspection Bureau in Inner Mongolia, Shaanxi Provincial Fiber Inspection Bureau.

1 Scope

This standard specifies the wash wool, wool tops and other heat inside the pile fibers using a method called test measuring moisture regain.

This standard applies to the determination of washed wool, wool tops and other plush fiber moisture regain.

2 Normative references

The following documents contain provisions which, through reference in this standard and become the standard terms. For dated references, subsequent Amendments (not including errata content) or revisions do not apply to this standard, however, encourage the parties to the agreement are based on research Whether the latest versions of these documents. For undated reference documents, the latest versions apply to this standard.

GB/T 8170 numerical rounding rules

3 Terms and Definitions

The following terms and definitions apply to this standard.

Moisture content measured sample under specified conditions. Wet sample weight and dry weight difference represents the percentage of dry weight ratio.

Textile materials, textiles containing water quality time.

Textile materials, textile products after a certain method to remove water quality.

Treated sample period, twice before and after weighing, does not exceed a predetermined range of mass.

In addition to the water sample after baking in the oven, with the oven attached balance Weigh the sample chamber process.

Principle 4

Pile fibers are oven dried test devices commonly used, mainly the heating wire air inside the oven is increased to a certain temperature, increasing fiber plush Dimensional thermal motion of water molecules can enhance the saturation vapor pressure of the air inside the oven, the relative humidity decreases, water molecules in the fiber moves air Partial pressure difference increases, causing the water molecules gradually migrate outward from the interior of the sample, constantly evaporating and escaping, so pile fibers continue to be dry, straight to quality is no longer changed. The quality of the sample at this time regarded as absolute dry mass (in fact plush fiber still contains about 0.5% water of crystallization).

Wet weight of the sample divided by the difference between the dry weight of the dry weight, expressed as a percentage, that moisture regain of the specimen.

5 Equipment and instruments

a) oven. a fitted balance, capable of weighing tank, automatic temperature control at (105 ± 2) °C of ventilated oven;

b) Balance. Range 200g, dividing the value of 0.01g;