It is the process by which hot rolled strip is introduced between rollers and then squeezed or compressed to the desired thickness
Cold rolling occurs with the metal below its re crystallization temperature( usually at room temperature).
Which increase the strength via strain hardening up to 20 %.
It also improve the surface finish and hold tighter tolerance.
In this 4HI OR CLUSTER mill is used.
Cold rolled products include sheets, strip, bar ,and rods.
These products are smaller than the products that are hot rolled.
Hot rolling can reduce the thickness more than the cold rolling.
Cold rolling material are in various condition
- full hard
- semi hard
- Quarter hard
- skin rolled
Full hard reduction thickness=50%
Other material having less reduction as compared to full hard.
In case of skin rolling also known as a skin pass having less reduction around 0.5-1 %.
It produced smooth surface, uniform thickness, and reduced the yield point.
It is used where ductility is required.