Cold Bend Test Apparatus IEC60811-1-4 for Cable Made by SUS304 Stainless Steel

1. Introduction

The cold bend test apparatus is designed according to IEC60811-1-4 clause 8.1 and figure 1, IEC60884-1, VDE0472, GB2951.4 and GB2099-94. It is applied to the test the cores of circular cross-section having an external diameter up to and including 12.5mm, sector shaped cores when it is not possible to prepare dumb-bells, and cables with an overall diameter up to and including 12.5mm or flat cables with a major axis dimension up to and including 20mm. The apparatus is consisted by one revolving mandrel and guiding device, and it shall be held in a suitable low temperature cabinet before and during the test.

2. Specification:

3. Picture

 4. Usage

1). The core to be test shall be represented by two samples of suitable length (overall diameter of the test piece is within 2.5mm to 12.5mm), and take properly size of mandrel as per test piece(the diameter of the mandrel shall be between 4 and 5 times of the diameter of the test piece).the apparatus shall be held in a refrigerator before and during the test, and the apparatus with the test piece in position shall be maintained in the refrigerator at the specified temperature for a period of no less than 16h, the cooling period of 16h includes the time necessary for cooling down the apparatus.

2). If the apparatus has been pre-cooled. a shorter cooling period is permissible, but not less than 4h provided that the samples have attained the prescribed test temperature, if the apparatus and test specimens have been pre-cooled, a cooling time of 1h after each test piece has been fixed to the apparatus is sufficient.During the test, remove a plug of the refrigerator and connect the operating handle to the winding core shaft, and rotate at a rate of one revolution in about 5s, the number of turns shall be as specified in the standard. The test piece rotate on mandrel and neatly wound into a tight spiral on the shaft. For flat cords, the mandrel diameter shall be base on the minor axis dimension of the test piece, which is wound on with its minor axis perpendicular to the mandrel

3). Evaluation of results: after the test, the test pieces shall be examined while stll on the mandrel. The insulation of both test pieces shall not show any crack when examined with normal or corrected vision without magnification.