Size Range:
OD: 5.0-329mm
WT:0.5-30mm
Length: max 12000mm

Method of Manufacture:

The tubes are manufactured from flat rolled strip, longitudinally welded continuously by the passage of an electric current

across the abutting edges without the addition of filler metal.

They are subsequently cold finished normally on both the inside and outside surfaces, where it is permissble to have both

an adherent layer of residual lubricant originating from the drawing process and visible traces of the internal weld upset.

If phosphate or other residues are detrimental to subsequent processing, their removal shall be the subject of an agreement

between the manufacturer and purchaser.

Delivery Condition:

The tubes are supplied in one of the following condition:

Cold finished/hard (cold finished as drawn) : BK

Cold finished/soft (lightly cold worked ): BKW

Annealed: GBK

Annealed (including de-scaling): GZF

Normalized: NBK

Normalized ( including de-scaling): NZF

It is permissible for tubes supplied in the GBK and NBK conditions to be discoloured, but they shall be free from loose scale.

Where tubes, in the GBK condition are required bright annealed, this shall be the subject of an agreement between the

purchaser and the manufactuer.

DOM(weld drawn-over-mandrel) Steel Tubing Characteristic:
Good concentricity
Good OD and ID tolerance
High Precision
Stable quality
Smooth Roughness

High Straightness

Production Processs:

Seamless tube and Cold Drawing or Cold Rolling Production