Cold drawn tubes for heat exchangers

Supplying conditions

In relation to their use, the tubes can be supplied in the following conditions:
1. ANNEALED (GBK)
2. NORMALIZED (NBK)
As concerns conditions at points 1 and 2, we have to point out that the heat treatment is effected in controlled atmosphere furnaces.
Consequently the tubes surfaces is perfectly oxide-free.
When not started at the request or order moment, seamless tubes are supplied annealed (in controlled atmosphere).

Steel: all the tubes are manufactured whit carbon steel according to the execution specifications. Alloyed steel on request.
Lenghts: cold drawn seamless steel tubes can be supplied in following lengths:
- Fixed: with tolerances according to execution specification.
- Tubes maximum lengths: 12 mts.
- Lengths over 12 mts. on demand.
Check and ispections: final check quality is guaranteed by following tests and checks:
- Electromagnetic non-destructive test on 100% of rough-shaped to drawn;
- Mechanical and technological tests according to the execution specifications;
- Electromagnetic non-destructive test on 100% of drawn tube.
Certifications: usually tubes are supplied with a test certificate according to the execution specifications.
Marking: according to the product type, the tubes can be marked in continuous for all the length with indelible ink or during packing with an identification label attached to the bundle.
Protection: to preserve the product, inside and outside are oiled with thin film protective oil, except customer different prescription.
Packing: the tubes are packed in round or hexagonal bundles of a maximum weight of 2000 kgs, bare or protected with polythene jute cloth, strapped on polyethylene bands. On each bundle is attached an identification label.