1. Cost

Since the hot-rolled base plate requires one fewer process than the cold-rolled base plate, the production cost of hot-rolled base plate galvanizing is lower than that of cold-rolled base plate galvanizing. The main cost differences lie in two items: annealing cost and cold rolling cost, while the costs of other processes for the two are roughly the same.

2、Quality and Performance

As the hot-rolled base plate only undergoes pickling and annealing to remove surface impurities, its surface is relatively rough, but the zinc layer adhesion is better, and the coating thickness tends to be 140/140 g/m². However, its thickness dimensional accuracy is not as high as that of the cold-rolled base plate; and since most of them have thick zinc layers, the zinc layer thickness control is also uneven. There is little difference in mechanical properties between the two, and the hot-rolled base plate even outperforms the cold-rolled one in some properties.

3、Application Fields

Due to its lower dimensional accuracy and surface quality compared with the cold-rolled base plate galvanized sheet, and greater thickness than the cold-rolled base plate galvanized sheet, the hot-rolled base plate galvanized sheet is often used for structural components that have low surface requirements but high strength and thickness requirements.

Examples include structural parts of home appliances such as washing machines and refrigerators, internal structural parts of automobiles, automobile chassis structural parts, passenger car bodies and roof panels, highway guardrails, cold-formed steel, etc.

Because the hot-rolled galvanized sheet has low cost, and with technological progress, its specification thickness has become larger and larger, its usage has gradually increased.

4、Grades

Common grades of hot-rolled galvanized sheets are DD51D+Z, HD340LAD+Z, HR340LA, HR420LA, HR550LA, etc.;

Corresponding grades of cold-rolled galvanized sheets are DC51D+Z, HC340LAD+Z, HC340LA, HC420LA, HC550LA, etc.;

There is also a type of grade that does not specify whether the base plate is cold-rolled or hot-rolled, such as DX51D+Z. Generally, this type of grade can be regarded as a hot-rolled galvanized sheet.