for tubes and profiles – HAKUFORM, HAKUDRAW

Some requirements and application areas demand seamless tubes (also with external and internal profiles), others welded tubes and/or welded profiles. Highly specialized HAKUFORM and HAKUDRAW forming lubricants are used for the sometimes vastly different production and processing methods.

Seamless tubes

After coating with DECORRDAL conversion layers (e.g., zinc phosphate for steel) and HAKUFORM/HAKUDRAW lubricants, the hollow blanks produced by hot rolling are drawn to tapering wall thicknesses and diameters. In some applications, the conversion layer can be omitted when special HAKUFORM high-performance lubricants are used. This forming process may be performed repeatedly depending on the desired final dimensions, whereby the pipes often have to be recrystallized before the subsequent drawing operation due to work hardening. The parts are often stripped (HAKUPUR and DECORRDAL products) before soft annealing. Recoating is required after heat treatment. In many cases a final bright drawing operation is applied: with HAKUFORM lubricants (also reactive ones), but without DECORRDAL zinc phosphating layer or only with a very thin phosphate coating.

Welded tubes and profiles

Welded tubes and profiles which are manufactured from hot or cold strip (roll-forging with HAKUFORM lubricants, then welding) are drawn similar to seamless tubes. Often only one drawing is needed when the width and thickness of the used strip is selected accordingly and close to the final dimensions.

Large-scale tubes

Large-diameter tubes (longitudinal or spiral welded, e.g., for pipelines) are expanded and compacted with expander oils (HAKUFORM EXP, HAKULUBE). KLUTHE expander oils are characterized by high process reliability, very low and uniform residues and easy removability.

Further processing

Numerous special HAKUFORM products are available for cutting to length via saw cutting, tube bending, and welding. CUSTOS 627 is used for pressure testing.