METHOD OF COLD-ROLLED AUTOMOBILE METAL SHEET PRODUCTION

摘要

FIELD: metallurgy. ^ SUBSTANCE: method includes continuous etching of hot-rolled strips in hydrochloric acid, rolling and coating. The main etching defects (metal under-etching and over-etching) are prevented and required steel quality is ensured, when etching is performed at regenerating acid concentrations supplied to etching tanks equal to 185-205 g/l. The strips moving velocity during etching process does not exceed 2 m/s. At the same time, the rolling on double-stand rolling mill is conducted in rolls having rough surface measured between Ra=2.0Ç2.5 mcm. The metal is exposed to pinch-pass rolling in rolls having roughness degree between Ra=3.5Ç6.5 mcm before it is coated in continuous hot galvanising facility. ^ EFFECT: improved consumer properties of cold-rolled galvanised auto metal sheet. ^ 1 ex