1. Scope This standard specifies the technical requirements and test methods of nylon pre-oriented yarns, which are used to guide production and are the basis for product inspection and rating. This standard applies to all specifications of pre-oriented yarn (POY) produced by our company. Mainly: semi-extinction, full-extinction, bright pre-oriented yarn with circular section and special-shaped section, the linear density is 11dtex-222dtex (10D-200D).
2. Terms and definitions 2.1 This standard uses the terms and definitions in GB/T3291.1, GB/T3291.3 and GB/T4146, and cites some clauses in GB/T16603-2008. 2.2 The product specifications of this standard are expressed in terms of linear density and the number of monofilaments. Considering the usage habits of downstream users, the linear density is expressed in denier (Den) on the product packaging label, such as 70D/24F. 2.3 The batch number of the product is set according to the "Principle of Product Numbering" of our company.
4 Test methods
4.1 Inspection of physical performance indicators and dyeing performance indicators
4.1.1 The linear density test shall be in accordance with GB/T14343.
4.1.2 The test of breaking strength and elongation at break shall be specified in GB/T14344.
4.1.3 Boiling water shrinkage test shall be carried out according to GB/T6505.
4.1.4 The dyeing uniformity test shall be regulated by FZ/T50008.
5.1.5 Dry uniformity test according to GB/T14346.
4.1.6 The oil content test shall be in accordance with GB/T6504.
4.1.7 Numerical rounding off: The numerical rounding off of each test result shall be in accordance with the provisions of GB/T8170, and the number of decimal places shall be reserved in Table 1.
4.2 Visual inspection
Appearance inspection is carried out tube by tube. The lighting adopts 40W double tube fluorescent lamp and charging tube, the illumination is required to be about 400lx, the observation distance is about 30cm, and the two end faces and cylindrical surface of each tube are visually inspected.
5 Sampling regulations
5.1 Inspection of physical indicators, under normal production conditions, conduct random inspections according to the sampling table. Others are specified in GB/T6502.
5.2 In the production line (spinning position) of re-spinning or open-spinning, the first falling product is sampled and tested for physical indicators.
5.3 The dyeing uniformity test is to sample the hosiery dyeing one by one (sampling inspection).
6 Evaluation of inspection results
The grade of the product is determined by the grade of the lowest index in physical index and appearance index.
7 Packaging and Identification
7.1 Put a small label on the inner wall of each bobbin, indicating the product specification, batch number, production date, spinning thread (spinning position) and order.
7.2 For the inspected products, mark the inner wall of each bobbin with a marker to distinguish.
7.3 The packaging materials used must meet the requirements of the company's "Technical Indicators for Raw and Auxiliary Materials".
7.4 Each wire cylinder is packed with plastic bags and packed according to different varieties, batch numbers and grades. The label on the outside of the box clearly indicates the product variety (semi-matte, full-matte, glossy), specification, batch number, grade, production date, spinning thread, number of spools, net weight and other information.
8 Storage
8.1 The product should be stored in a dry, ventilated and dark warehouse, and the storage environment temperature should be less than 35℃.
8.2 The large packing box is allowed to stack 2 layers, and the small packing box is allowed to stack less than 10 layers.
