Method for pre-expanding cold-shrinking cable accessory

Abstract

The invention aims to provide a method for pre-expanding a cold-shrinking cable accessory, which comprises the following steps: expanding the cold-shrinking cable accessory by using a steel wire tensioned between two corresponding expansion discs; sleeving a support tube on an expansion bar of which one end is provided with an expansion cone head, and sleeving an end cap at the other end of the expansion bar; pushing the end cap through a cylinder piston so as to forward push the expansion bar and the support tube together along the axial direction of the cable accessory till the expansion cone head of the expansion bar is fully pushed out of the other end of the cable accessory; and finally, removing the end cap, the expansion bar and the steel wire in turn, and shrinking and clasping the cable accessory outside the support tube so as to finish pre-expanding. The cable accessory is expanded by adopting the steel wire, the steel wire material is easily obtained and does not need to bepolished, the steel wire is cheaper than a steel bar, and the steel wire for expanding the cable accessory can be pulled out by using mechanical operation, so the labor intensity of operators is lightened, the expanding speed is high and the work efficiency is improved; and the surface of the steel wire has good degree of finish, so the steel wire has little damage to the inner wall of the cold-shrinking cable accessory, ensures the safety of the cable accessory and improves the quality of a product.

Description

technical field [0001] The invention belongs to the technical field of electric equipment accessories, in particular to a pre-expansion method for cold-shrinkable cable accessories. Background technique [0002] Cold-shrinkable cable accessories are commonly used as a power accessory. The existing pre-expanded cold-shrinkable cable accessories mainly use steel rods for pre-expansion. The heat treatment requires high hardness and a certain shape. The most critical thing is that the surface finish of the steel bar is relatively high. If the surface finish is not done well, it is easy to scratch the inner surface of the cold-shrinkable cable accessory, and the pre-expansion speed is too fast. It will also scratch the inner surface of the product, causing serious quality problems; and the steel bar is not easy to pull out, the labor intensity of the operator is relatively large, and it is easy to cause the steel bar to break when the steel bar is pulled out, and the cost of the ...

AI Technical Summary

Problems solved by technology

[0002] Cold-shrinkable cable accessories are commonly used as a power accessory. The existing pre-expanded cold-shrinkable cable accessories mainly use steel rods for pre-expansion. The heat treatment requires high hardness and a certain shape. The most critical thing is that the surface finish of the steel bar is relatively high. If the surface finish is not done well, it is easy to scratch the inner surface of the cold-shrinkable cable accessory, and the pre-expansion speed is too fast. It will also scratch the inner surface of the product, causing serious quality problems; and the steel bar is not easy to pull out, the labor intensity of the operator is relatively large, and it is easy to cause the steel bar to break when the steel bar is pulled out, and the cost of the steel bar is relatively high. The cycle is relatively long and the cost is high, which directly affects the processing efficiency and increases the cost of pre-expansion processing

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