The hot rolled tubes can be further processed by cold working. This is done either by cold rolling or by cold drawing. The cold working gives the tubes narrower tolerances, better surfaces and a strain hardening that often gives a better machinability than the hot rolled tubes.
The cold worked tubes can also be delivered in the ground condition.
Cold worked tubes
Cold rolled tubes
The cold rolling is carried out in a pilger rolling process.
Cold drawn tubes
Cold drawing gives the tubes the same properties as the equivalent cold rolled tubes.