GB/T 47633-2026Test method for the thermal ageing properties of dipped cords and yarns (English PDF)

6.2 Sampling and Sample Preparation

6.2.1 Resin-coated curtain. The surface layer of the resin-coated curtain fabric should be removed, and then the resin-coated curtain should be pulled out from different positions at least.200mm from the edge of the fabric. The wire is prepared into a sample with a length of not less than 500 mm.

6.2.2 Impregnated yarn. The outer 3 layers or more should be removed, and then a sample of not less than 500 mm should be prepared.

6.2.3 Glue-impregnated rope. The outer 3 layers or more should be pulled off, and then a sample of not less than 1200 mm should be cut and prepared.

6.2.4 The specimens should be free from defects such as twisting, untwisting, torsion, and wrinkles. Before the test, the specimens should be sealed in an opaque bag and kept for later use.

6.3 Number of Samples The number of test samples should be no less than 26, of which 12 are used for testing at room temperature and 14 are used for thermal aging testing.

6.4 Preparation of Rubber Modules

6.4.1 The rubber module can be prepared using either heat-aged samples or unaged samples. Specifically, the rubber module prepared using heat-aged samples... The adhesive module should not be subjected to heat aging again; it should be directly tested for adhesion performance after equilibration.

6.4.2 The preparation of rubber modules for testing the adhesive properties of impregnated cords and yarns shall be carried out in accordance with GB/T 2942, with the sample embedded for a length of... The thickness is 10mm, the rubber module size is 10mm×10mm×20mm, and the rubber compound formulation and vulcanization test conditions should meet the requirements of the test sample. The requirements for the species or the test shall be determined through consultation between both parties.

6.4.3 The preparation of rubber modules for the adhesive performance test of impregnated cords shall be carried out in accordance with the provisions of GB/T 31333, including the rubber compound formulation and vulcanization. The test conditions should meet the requirements of the sample type or be determined through consultation between the test parties.

Note. Due to differences in rubber formulations and vulcanization test conditions, the test data are not comparable.

6.5 Test Conditions The heat aging test conditions for rubber-impregnated cords, rubber-impregnated ropes, and rubber-impregnated yarns shall comply with the relevant product standards or the agreement between the testing parties. Conditions typically include test temperature, test time, etc. Common test conditions are listed in Appendix A.

Note. The test data are not comparable due to different thermal aging test conditions.

6.6 Balancing of the Rubber Module After vulcanization, the rubber module should be equilibrated under the conditions specified in

6.1 for no less than 16 hours and no more than 96 hours.

7.1 Thermal aging test

7.1.1 Turn on the aging test chamber and set the test temperature of the aging test chamber.

7.1.2 After the temperature of the heat aging test chamber reaches the set temperature, clamp one end of the sample or rubber module with a clip and hang it in the heat aging chamber. On the rotating tray inside the oven.

7.1.3 Set the thermal aging time and start the test.

7.1.4 After the specified aging time has been reached, remove the specimen from the thermal aging test chamber. The removed specimen should be left to acclimate without stress. Then it cools down.

7.1.5 During the test, the sample and the rubber module should not be subjected to heat aging test in the same test chamber at the same time.

7.2.1 Equilibrate the sample under the conditions given in

6.1 for (24±2) h.

7.2.2 Determine the breaking strength, elongation at break, and elongation at constant load of the specimens before and after aging in accordance with GB/T 32108. performance.

7.3 Adhesion performance test

7.3.1 The bonding performance test of PVC-impregnated cords and PVC-impregnated yarns shall be conducted in accordance with the provisions of GB/T 2942, and the tensile testing machine clamp moving speed shall be [not specified]. It is (100±10) mm/min.

7.3.2 The adhesive performance test of the resin-impregnated cord shall be conducted in accordance with the provisions of GB/T 31333, and the moving speed of the clamps of the tensile testing machine shall be (100±) 10) mm/min.

8.Experimental Results The performance retention rate of the ethylene-impregnated cord, ethylene-impregnated rope, and ethylene-impregnated yarn samples before and after aging was calculated according to formula (1). The test results were then processed according to... GB/T 8170 stipulates rounding to one decimal place.