FZ/T 12018-2019Compact spun combed cotton grey yarn (English PDF)

4.2 The production process and raw material code of compact spun combed

cotton grey yarn are indicated by English letters. CP is the code for compact spinning. JC is the code for combed cotton.

4.3 When the compact spun combed cotton grey yarn is marked with a code, the production process code and raw material code of the yarn shall be marked before the line density.

Example 1: The compact spun combed cotton grey yarn with a linear density of

14.8tex shall be written as CP JC 14.8 tex.

Example 2: The compact spun combed cotton grey double-stranded thread with a linear density of 14.8tex shall be written as CP JC 14.8tex × 2.

5.1 Items

The technical requirements for compact spun combed cotton grey yarn (thread) include 9 items: linear density deviation rate, linear density variation coefficient, single yarn (thread) breaking strength, single yarn (thread) breaking strength variation coefficient, evenness variation coefficient, kilometer thick section (+50%), kilometer neps (+200%), 100,000-meter yarn defect, hairiness index H value or 2mm hairiness index.

5.2 Grading regulations

Annex B (normative)

Test method for hairiness index H value

B.1 Principle

The principle of photoelectric hairiness detection is: When the continuously moving yarn passes through the detection zone, the hairiness of the protruding yarn body scatters the continuous monochromatic parallel light in the detection area. The scattered light is accumulated by the lens system and detected by the photoelectric sensor. The electrical signal output by the detector can be processed by the circuit to provide various results indicating the characteristics of yarn hairiness.

B.2 Instruments

B.2.1 Yarn frame: enables the yarn of various packages to be unwound under

a certain tension, and prevents the yarn from being accidentally elongated or damaged.

B.2.2 Detector: photoelectric measuring groove and roller traction device that

can make the yarn pass through the measuring groove at a certain speed.

B.2.3 Controller: control the testing process and complete the processing of the

electrical signal of yarn hairiness. Obtain various test results for display or printing (hairiness H value, sH value, hairiness spectrogram, hairiness unevenness curve and so on.)

B.3 Sampling quantity and test times

B.3.1 Sampling quantity of single yarn and strand: 10 rolled packages.

B.3.2 Test times: 1 test for each rolled package.

B.3.3 The sampling quantity and test times can be specified as needed. The recommended sampling length is 250m~2000m. The length for conventional test is 400m. The length for product acceptance arbitration test is 1000m.

B.4 Atmospheric conditions

B.4.1 The humidity conditioning of the specimen shall be balanced for 24h in accordance with the standard atmosphere in GB/T 6529, that is, when the temperature is (20.0±2.0)°C and the relative humidity is (65.0±4.0)%. When more than one test is required for a large and tight sample rolled package or for

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