Continuous piercing method for seamless steel tube

Abstract

The invention discloses a continuous piercing method for a seamless steel tube, comprising the following steps of: (1) obtaining a heated blank from a feeding work station, conveying the blank to a waiting work station; (2) conveying the blank from the waiting work station to a processing work station for the first piercing so as to form a hollow billet; (3) conveying back the hollow billet to the waiting work station; (4) conveying the hollow billet from the waiting work station into the processing work station for performing secondary piercing on the hollow billet or rolling the hollow billet into a pierced billet; (5) conveying the hollow billet processed with the secondary piercing or the rolled pierced billet into next work procedure. The method has the benefit that, in comparison with the prior art, the method can cycle the hollow billet back to the waiting work station and the processing work station, and can roll or perfume the secondary piercing on the hollow billet without independently setting equipments and work procedures, so that work procedures are reduced, processing equipments are reduced, work cost is decreased, work efficiency is improved, energy wastage in secondary heating is avoided, burning loss is reduced, and yield is improved.

Description

technical field [0001] The invention relates to a method for cross-rolling piercing and secondary rolling extension of a large-diameter hot-rolled seamless steel pipe, in particular to a method for saving seamless steel pipe piercing and rolling processes. Background technique [0002] The traditional hot-rolled seamless steel pipe production process consists of three processes of piercing, rolling, and sizing, and correspondingly requires three unit equipment to complete the three processes respectively. Some seamless steel pipes also need to be pierced twice. However, the existing piercing process can only be used for one-time piercing to produce capillary tubes, while rolling to form blank tubes and performing the second piercing all need to be completed with other equipment, and new processes need to be set up. This increases the production process of seamless steel pipes, increases production costs, and reduces work efficiency. Especially when the second piercing is pe...

AI Technical Summary

Problems solved by technology

However, the existing piercing process can only be pierced once to produce capillary tubes, while rolling to form blank tubes and the second piercing need to use other equipment to complete, and a new process needs to be set up

This increases the production process of seamless steel pipes, increases production costs, and reduces work efficiency.

Especially when the second piercing is performed, the capillary needs to be reheated again, which greatly wastes energy, and may cause re-burning and reduce the yield

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