Cold rolling mill machine is a kind of equipment to process the sheet or strip of metal (usually steel or aluminum) to achieve the required thickness and properties by rolling several times at room temperature.
Cold rolling process can improve the surface quality, mechanical properties and dimensional accuracy of sheet metal, is a very important part of the metallurgical industry.
What is a cold rolling mill machine?
Cold rolling mill is an important equipment for metal processing, which is used to roll metal sheets and strips to the required thickness at room temperature. According to the operation mode and application requirements, cold rolling mills are mainly divided into two types: reversible cold rolling mills and continuous cold rolling mills. They have their own characteristics in terms of working principle, structure and scope of application.
Principle of operation of reversible cold rolling mill machine
Reversible Cold Rolling Mill (Reversible Cold Rolling Mill) is a kind of cold rolling equipment that can realize the reciprocating passage of steel strip in the mill by changing the direction of rotation of rolls.
1. Single Stand Reciprocating Rolling
- The steel strip is unwound through the inlet coiling device (Uncoiler) and passes through the mill stand into the outlet coiling device (Coiler).
- The strip can pass through the same mill stand repeatedly during the rolling process, with the direction of the rolls being controlled by a motorized drive system that reverses the direction of the rolls.
- Each pass is called a “pass” and each pass gradually reduces the thickness of the strip until the target thickness is reached.
2. Thickness Control
- Equipped with an automatic thickness control system (AGC), the roll gap is adjusted according to the strip thickness measured in real time during the rolling process to ensure thickness accuracy.
3. Tension Control
- Tension is applied by the coiling devices on both the entrance and exit sides to prevent wrinkles or breakage of the steel strip during the rolling process.
reversible cold rolling mill machine
continuous cold rolling mill
Principle of operation of continuous cold rolling mill machine
Continuous Cold Rolling Mill is a kind of multi-stand tandem arrangement, can realize the continuous rolling of steel strip of large-scale cold rolling equipment.
Multi-stand tandem rolling
- After the steel strip is unfolded from the entrance coiling device, it passes through a number of tandem mill stands (usually 4-6 stands), and is gradually thinned to the target thickness under the compression of the rolls.
- Each stand bears part of the thinning volume, and the overall rolling pressure is evenly distributed to improve rolling accuracy and stability.
Continuous operation
- The steel strip passes through the mill continuously at high speed without stopping for reversing, which improves production efficiency.
- Coordination between each stand is maintained by a tension control system, ensuring smooth steel strip operation.
Thickness and Tension Control
- Thickness control: Each stand is equipped with an independent AGC system that adjusts the roll gap based on feedback from thickness sensors to ensure uniform thickness throughout the line.
- Tension control: Entrance, exit and between racks are equipped with tension control devices to ensure that the steel strip is free from defects such as waves and cracks.