Method for removing scales on surface of hot-rolled stainless steel strip

Abstract

The invention discloses a method for removing scales on the surface of a hot-rolled stainless steel strip. The method comprises the following steps of: performing abrasive blasting treatment on the hot-rolled stainless steel strip to be treated, wherein the abrasive blasting treatment refers to spraying of mixed slurry of water and an abrasive material, and the percent by volume of the abrasive material in the slurry is 30%-40%; after the abrasive blasting treatment, performing primary grinding and scrubbing on the steel strip; after the primary grinding and scrubbing, performing acid-washing on the steel strip with diluted sulphuric acid; cleaning the steel strip subjected to acid-washing by the diluted sulphuric acid by water, and then performing secondary grinding and scrubbing on the steel strip; after the secondary grinding and scrubbing on the steel strip, performing acid-washing on the steel strip with mixed acid of nitric acid and hydrofluoric acid; and after the acid-washing with the mixed acid, cleaning the steel strip with water, then performing third grinding and scrubbing on the steel strip, and finally, washing the steel strip with water. With the slurry spraying technique, as the abrasive material is mixed with the water, the scales on the surface of the hot-rolled stainless steel strip can be removed more effectively; and the consumption quantity of acid in subsequent steps is greatly reduced.

Description

technical field [0001] The invention relates to a method for removing oxide scales on the surface of hot-rolled stainless steel strips. Background technique [0002] The surface oxide scale removal process of hot-rolled stainless steel strip is an important process in the production of cold-rolled stainless steel products, and the quality of the product will directly affect the quality of cold-rolled stainless steel products produced by subsequent processes. Such as figure 1 As shown, at present, in the production process of stainless steel strip, especially in the process of removing scale on the surface of hot-rolled stainless steel strip, phosphorus breaker + shot blasting machine (dry shot blasting method) is generally used to remove phosphorus mechanically, and then Water spray cleaning + sulfuric acid pickling + water spray cleaning + abrasive scrubbing + mixed acid pickling + water spray cleaning + nylon scrubbing + water spray cleaning, in which the shot blasting m...

AI Technical Summary

Problems solved by technology

like figure 1 As shown, at present, in the production process of stainless steel strip, especially in the process of removing scale on the surface of hot-rolled stainless steel strip, phosphorus breaker + shot blasting machine (dry shot blasting method) is generally used to remove phosphorus mechanically, and then Water spray cleaning + sulfuric acid pickling + water spray cleaning + abrasive scrubbing + mixed acid pickling + water spray cleaning + nylon scrubbing + water spray cleaning, in which the shot blasting machine uses carbon steel sand, the production method of this process The current problem is that the consumption of acid is large, and the nitrogen-containing waste gas discharged from the mixed acid pickling section also pollutes the environment. Under-pickling often occurs, and there are residual acid spots and dirt on the surface of the strip after pickling. And other issues

Images