Summary of Defects in the Steel Strip Pickling and Cold Rolling Processes
Release Date:
2022-06-23
Author:
Hengyuan Industry and Trade
Summary of Quality Defects in Each Cold-Rolling Process The production process flow for cold-rolled strip steel primarily includes:
Hot-rolled raw material, push‑pull hydrochloric acid pickling, single‑stand reversible cold rolling, electro‑degreasing and rinsing, full‑hydrogen (or nitrogen–hydrogen) annealing furnace, single‑stand skin‑pass rolling, heavy‑coil slitting (or cross‑slitting), stretch‑bend straightening, packaging, storage, and transportation, among others.
Today, we’re compiling and sharing the quality defects observed in the pickling and rolling processes of cold‑rolling. At your request, we’ve included relevant images, and we’ll continue to systematically document and summarize defects from other process steps in future updates.
1. Pickling Process
During the pickling process, improper control of process parameters, careless operation, or operational errors can compromise the quality of pickling and give rise to various defects. These defects can be broadly categorized as follows:
Pickling bubbles (hydrogen embrittlement), over‑pickling, under‑pickling, rusting, inclusions, scratches, and indentations account for approximately 2% of defects in cold‑rolled products.
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