What is the working principle of High Precision Copper Alloy Strip Cold Rolling Mill

      By relying on the reverse rotation of high-precision rolling rolls, a huge rolling pressure is applied to the copper alloy strip entering the roll gap, causing plastic deformation of the strip, thinning of thickness, width extension, and dense structure. At the same time, through roll gap adjustment, tension control, speed closed-loop, bending/tilting roll, and plate shape control system, high-precision thickness, flat plate shape, and smooth surface precision cold rolling forming can be achieved.

1、 Overall workflow

Open book feeding

      The raw copper alloy coil (hot-rolled billet/semi-rigid strip) is uniformly released from the uncoiler and fed into the inlet of the rolling mill to establish a stable inlet tension.

Precise positioning of roller seam

      The hydraulic pressing system fine tunes the gap between the upper and lower rollers, sets the roller gap according to the target thickness, and locks it with micrometer level accuracy.

Reverse rotation rolling of rolling mill

      The main motor drives the upper and lower work rolls to rotate in the opposite direction at a constant speed, relying on the frictional force on the roll surface to bite the copper strip into the roll gap.

Plastic deformation thinning and shaping

      The copper strip is subjected to compression, friction, and shear between the roller gaps

Thickness is compressed thin

Metal grains are elongated and densified

      Internal stress redistribution leads to increased strength and hardness

      The surface is crushed by the mirror surface of the rolling mill, becoming shiny and smooth

Tension closed-loop control

      Establish a constant tension at the entrance and exit of the coiling machine to prevent the copper strip from deviating, wrinkling, and breaking, ensuring smooth rolling and uniform thickness.

Automatic correction of plate shape

      Equipped with bending rollers, downward tilting rollers, cooling and lubrication, and plate shape detection:

Correct edge waves, medium waves, and sickle bends to ensure that the entire copper strip meets the standard for flatness and evenness.

Roll up and receive materials

      The high-precision thin copper strip after rolling is neatly wound by a constant tension coiling machine to become the finished precision copper alloy strip.

2、 Key auxiliary principles

Hydraulic compression principle

      Adopting hydraulic AGC thickness automatic control, real-time detection of outlet thickness, dynamic adjustment of roll gap, compensation for roll thermal expansion, bounce, and material hardness fluctuations, achieving high-precision thickness control of ± a few micrometers.

Process lubrication and cooling

      Rolling oil spray: reduces friction between the rolling mill and copper strip, cools down, removes iron powder impurities, ensures smooth surface, prevents scratches, and controls roll temperature.

Multi roll structure principle (commonly used for high precision)

      Ordinary two roll cold rolling mills are prone to deformation, while high-precision copper strips are often produced using four roll, six roll, and twenty roll cold rolling mills

      The work roll is responsible for rolling, while the support roll bears enormous pressure to reduce the bending deformation of the rolling roll, in order to produce extremely thin and high-precision copper alloy strips.

3、 Applicable processing objects

      High precision ultra-thin copper strips such as brass, phosphor copper, beryllium copper, purple copper, copper nickel alloy, etc. are used for electronic terminals, connectors, 5G RF, new energy, precision stamping, etc.

4、 Summary Simplified Version

      By using rolling mill mechanical extrusion and plastic deformation to thin copper strip, combined with hydraulic AGC thickness self-control, constant tension, bending roll plate shape correction, lubrication and cooling, ordinary copper billet is rolled into high-precision copper alloy strip with precise thickness, flat plate shape, mirror surface, and uniform performance.