Verification of Methods for Extending the Life of Cold drawn Tube Pulling Machine Chain
The large chain used in the cold drawing and tube drawing machine was originally updated as a whole during major repairs, but later changed to depend on the degree of chain wear. Sometimes only some chain plates are replaced, and the rest continue to be used until they break before replacing the chain plates. With the continuous expansion of production scale and the increasing output year by year, the consumption of spare parts for the cold drawn tube machine chain continues to increase, seriously affecting the improvement of cold drawn tube production.
Therefore, an analysis and study were conducted on the wear of the cold drawn tube drawing machine chain, and measures were taken to extend the service life of the chain. The 20t cold drawing and pipe drawing machine adopts a single row chain drive. The working process of pulling steel pipes is as follows: the vise on the trolley clamps one end of the steel pipe, the tail hook of the trolley hooks one end of the inner chain plate of the chain, and under the action of the driving wheel, the pulled steel pipe moves in a straight line in one direction until the steel pipe is pulled completely, and the tail hook of the trolley automatically disengages.
When the cold drawing machine pulls steel pipes, the entire inner chain plate enters the gap between the two teeth of the pentagonal wheel. When the driving wheel rotates in the W direction, the A end of the inner link plate first meshes with one tooth of the pentagonal wheel, and then the other tooth of the pentagonal wheel meshes with the B end of the inner link plate. Under heavy load, the pentagonal wheel pushes the B end of the inner link plate forward.
Due to the fact that the rotation angle between the B end hole of the inner chain plate and the pin shaft is greater than that of the A end during steel pipe drawing, under unidirectional gravity transmission, the wear of one end hole of the inner chain plate is much faster than that of the other end. When a new inner chain plate is put into use and the B end is pulled apart, the wear of the A end hole is only about 5mm to 8mm.
If continued to be used, the B-end hole will soon experience fatigue fracture. If it is turned around (A and B ends facing each other) at this time, it can extend the service life of the inner chain plate. The results indicate that the use of chain turning for cold drawing and tube drawing machines is feasible.
