Industry News

Why are twisted wires defective?

Published by admin September 25,2021

The main reasons for the defects of twisted wires are excessive twisting, single wire breakage during twisting, surface scratches, scratches on the core, loose strands of single wire, and single wire grooving or surface defects. The following is an analysis of why these phenomena occur.

 

1. Over-twisting refers to the twist-shaped phenomenon of excessive twisting during the twisting process. And what are the reasons:
1) The number of turns of the twisted wires on the traction wheel are not enough, generally less than 4 turns, the friction is too small and slips, resulting in excessive twisting.
2)The tension of the take-up wire is loose or the take-up reel does not rotate while the rotating body is still rotating, resulting in excessive twisting.

 

2. Why the single wire breaks when twisted
1) The wire core is broken due to excessive pay-off tension.
2)When the single wire is drawn, it is loose and disorderly, the wiring is not good, and the crimping wire crosses the wire, causing the wire core to break.
3)The material of the single wire itself has cracks, and the mechanical properties are not good and brittle.
4) Improper installation position of pay-off reel, axial shaking, causing wire breakage.
5)The single wire jumps out of the pulley groove and the mechanical jam is broken.

3. Why the surface of the twisted wires are scratched and the core is scratched

Usually one is the wear of the thread nozzle on the spool, the other is that the single wire jumps out of the pulley, the third is that the thread is worn through with a wooden or plastic tube, the fourth is that the positioning pin on the push board of the traction equipment is damaged, the fifth is that there is foreign matter in the die the reason.

 

4. What are the reasons for the back strands and loose strands of single wires in bundles and twisted wires?
1) The pay-off tension is uneven, the tension is tight, and the tension of the thread core goes too much, causing back strands.
2) The die hole is too large to properly adjust the tension.
3) Improper die position, unreasonable twist angle, fourth, relatively large pitch, etc.

5. Causes of single wire grooves or surface defects in the twisted wires:

The defects such as pits, scars, triangle cracks, slag inclusions on the surface of the single wire are mainly caused by the material. Of course, the surface of the wire core is chipped, and the unreasonable hole pattern of the drawing die is not ruled out. At this time, it needs to be specific Specific analysis of the situation. The continuity of grooves on the surface of the wire core is generally caused by the wire drawing. The lubrication condition of the drawing wire is deteriorated and the surface is sticked to aluminum. The non-continuous grooving may be caused by foreign matter sticking to the stranding die.

JZD cable manufacturer provides different types of wires and cables, like twisted wires, house wiring cable, power cable, industrial cable, solar cables and others. We have more than 20 years of experience in this industry, please contact us for more information .