Hot rolling and cold rolling are two commonly used methods in steel processing, and their difference lies in the different processing temperatures. Hot rolling refers to processing steel billets into required shapes at high temperature, while cold rolling refers to processing at normal temperature. Let's take a closer look at the differences, advantages and disadvantages of these two treatments.

hot rolling

operation sequence/order

1. Blank preparation: send the blank to a heating furnace for preheating, so that it can reach a suitable processing temperature.

2. Processing: the preheated billet is sent to a rolling mill for processing, and the billet is processed into the required shape through continuous rolling and stretching.

3. Cooling: send the processed steel into cooling equipment for cooling, so that it can reach room temperature.

merits and demerits

Advantages:

1. High production efficiency: high hot rolling speed and high production efficiency.

2. High precision: In the process of hot rolling, steel is easy to deform and can be made into more accurate shapes.

3. Energy saving: In the hot rolling process, the heat energy of steel itself can be fully utilized to save energy.

Disadvantages:

1. Poor surface quality: During hot rolling, scale and rust are easily generated on the steel surface, which affects the surface quality.

2. High cost: Hot rolling needs a lot of energy and equipment, and the cost is high.

cold rolling

operation sequence/order

1. Prepare billet: send the billet to pickling equipment for rust removal and cleaning.

2. Processing: the cleaned billet is sent to a cold rolling mill for processing, and the billet is processed into the required shape through continuous rolling and stretching.

3. Annealing: the processed steel is sent to an annealing furnace for annealing, so that it reaches a proper hardness.

4. Cooling: the annealed steel is sent to a cooling device to be cooled to room temperature.

merits and demerits

Advantages:

1. Good surface quality: In the process of cold rolling, the surface quality of steel is good, and it is not easy to produce scale and corrosion.

2. Low cost: in the cold rolling process, the energy consumption is low and the cost is low.

3. Good uniformity: In the cold rolling process, the hardness and uniformity of steel are good.

Disadvantages:

1. Low production efficiency: slow cold rolling and low production efficiency.

2. Low precision: In the cold rolling process, the steel has high hardness and is not easy to deform, and the manufactured shape has low precision.