Line Quenching of Spiral Pipe
The primary task of spiral pipe line quenching is to control the deformation and rolling finishing temperature, the austenite grains after rolling finer, after quenching to obtain fine martensite foundation. Japan's high-performance line quenching process by rolling deformation and heat treatment line combination, that is, through the rolling deformation during distribution, the final rolling temperature control, control of intermediate cooling in combination with heat treatment temperature control line to give than hot-rolled conventional quenching better organization and performance.
Spiral pipe line quenching is set by the rolling machine or Save machine (if rolling units shall be placed in the position of a given machine and Save cabin tube and reducing the role of detached given machine) after rolling steel by water quenching online means for rapid cooling (spray or immersion), rapid cooling from a high temperature steel pipe down and get the process martensite. Online hardened steel through reheating furnace heated to a temperature of less than 4J less, holding for some time and in an appropriate manner to cool to room temperature, to give the final tempering sorbite organization.
When rolling spiral pipe production line is equipped with line quenching process must be given reducing machine configuration after the detached or detached and fixed machine reducing machine as one, both detached underway given reducing effect. This is because the lower tempering temperature spiral steel after quenching, tempering, even if no more than 720 degrees (generally tempering temperature of 500-650 ℃, except for very special circumstances), be given at this temperature reducing, mill deformation resistance load very large bureau, and it also causes greater stress and bending steel. That must be so deformed before the completion of the quenching pipe heat tempered.