Product information:
This test conforms to the standard requirements of IEC540. It is used for cold bend test of the circular insulation wire core whose diameter is small and the sector-shaped insulation wire core which cannot be used for dumbbell. The apparatus shall be held in a refrigerator before and during the test.
The diameter of the mandrel shall be between 4 and 5 times the diameter of the test piece (see below).
The mandrel shall be uniformly rotated at a rate of one revolution in about 5 s and the number of turns shall be as specified in the following table.
Technical parameters:
1. Diameter of samples: 2.5～12.5 (mm)
| Overall diameter (d) of the test piece (mm) | Number of turns |
| d≤2.5 | 10 |
| 2.5＜d≤4.5 | 6 |
| 4.5＜d≤6.5 | 4 |
| 6.5＜d≤8.5 | 3 |
| 8.5＜d | 2 |
2. Diameter of pipe: 3、4、5、6、7、8、9、10、12、14、16（mm）
3. Diameter of test bar: 9.6、12.5、16、20、25、31.5、40、50(mm)