GB/T 2951.31-2008Common test methods for insulating and sheathing materials of electric and optical cables -- Part 31: Methods specific to PVC compounds -- Pressure test at high temperature -- Test for resistance to cracking (English PDF)

Foreword

GB/T 2951 "cable and the cable Common test methods for insulating and sheathing materials" is divided into 10 parts.

--- Part 11. General test methods for measuring the thickness and overall dimensions --- --- mechanical tests;

--- Part 12. Common test methods --- Thermal aging methods;

--- Part 13. General test method for determining the density method --- --- --- Water absorption tests - Shrinkage test;

--- Part 14. Common test methods --- low temperature test;

--- Part 21. elastomeric compounds specific test method Ozone resistance --- --- --- Hot set test - Mineral oil immersion test;

--- Part 31. Methods specific to PVC compounds - Pressure test --- --- high temperature resistance to cracking;

--- Part 32. Methods specific to PVC compounds - Loss of mass test --- --- thermal stability test;

--- Part 41. polyethylene and polypropylene compounds - Test methods --- --- ESCR test melt index measurement Measurement Method --- direct combustion of polyethylene in carbon black and/or mineral filler content --- thermal gravimetric analysis (TGA) measurements of carbon Black --- microscopy to assess the content of carbon black dispersion in polyethylene;

--- Part 42. polyethylene and polypropylene compounds - Test methods --- After heat treatment the tensile strength and elongation at break test Increase the quality of experience --- --- winding test air test after thermal aging was measured after heat treatment --- --- long-term thermal stability Qualitative tests --- copper-catalyzed oxidative degradation test methods;

--- Part 51. Methods specific to filling compounds - Drop point --- --- --- oil separator temperature brittleness --- --- total acid corrosion this part of the National Standardization Technical Committee of wire and cable.

This section is drafted. Shanghai Electric Cable Research Institute.

1 Overview

3 Scope

Test conditions and test parameters specified in this section apply to the cable, the most common type of cable, wires and cords insulation and sheathing materials.

4 Type tests and other tests

Test methods described in this section is first used as a type test. Some pilot projects to test its type testing and regular of (Such as routine test) conditions are fundamentally different, this section has been pointed out these differences.

5 Pretreatment

All tests shall be insulated and sheath material extruded or vulcanized (or crosslinking) after storage for at least 16h before proceeding.

6 Temperature test

Unless otherwise specified, the tests should be carried out at ambient temperature.

7 Intermediate value

When the test data obtained proper number in ascending or descending order, if the number of valid data is odd, the median is positive A middle value; if even, the median is the average of the middle two values.

GB/T 2951.31-2008/IEC 60811-3-1. 1985