In fact, the steel billets from the steel mill are only semi-finished products, and they must be rolled in the rolling mill before they can become qualified steel products. Hot rolling and cold rolling are two common rolling processes.
The rolling of steel is mainly hot-rolled, and cold-rolled is mainly used to produce small-sized sections and sheets.
The following are common cold-rolled and hot-rolled steel conditions:
Wire: 5.5-40 mm in diameter, coiled, all hot-rolled. After cold drawing, it belongs to cold drawn material.
Round steel: In addition to the bright material with precise dimensions, it is generally hot-rolled, and there are also forging materials (forging marks on the surface).
Strip steel: both hot-rolled and cold-rolled, and cold-rolled materials are generally thinner.
Steel plates: cold-rolled plates are generally thinner, such as automobile plates; there are many hot-rolled medium and heavy plates, with similar thicknesses to cold-rolled plates, and their appearance is obviously different.
Angle steel: all hot rolled.
Steel pipe: Both hot-rolled and cold-drawn are available.
Channel steel and H-beam: hot rolled.
Reinforcing bar: hot rolled material.
