Forming Parts

Forming parts are products made using the same cold-extrusion production process as for connecting elements.

They are generally distinguished by a more complex geometry and, therefore, can be made only using a multistage pressing process. Some examples for such products are door hinge axles, drive shafts, locating pins, cores for rubber-to-metal elements, ball pins or bushings.

Development processes carried out jointly with our customers have often turned out that there is a more efficient production variant of cold forming available for mechanical parts processed so far rather expensively. To do so, some minor modifications are only required on the product which will not adversely affect its functionality. ESKA applications engineering is always by the side of our customers to provide adequate support at any time.


The use of forming parts features a high technical and economic potential for our customers:


  • parts with big diameter gradations can almost be made without material removal/waste.
  • Additional functional elements can be fitted in the same process step (e.g. gearings, longitudinal slots etc.)
  • very high production output rates are possible (100 to 300 pieces/min)
  • strain hardening upon forming makes heat treatment superfluous, as the case may be
  • as compared to turning parts, there is a substantially higher load-bearing capacity in forming direction


The range of forming parts at ESKA is generally defined as follows:


  • shank diameter M4 up to max. M40
  • maximum outer diameter 50 mm
  • length 6 mm up to 220 mm
  • cup depths approx. 40 mm


As to the complex forming parts, ESKA has particularly specialized in the field of hollow parts and parts with collapse die.


Hollow parts: particularly high cost saving as compared to cutting manufacture by minimizing of material waste


  • wall thickness: 1.3 mm up to 5.8 mm
  • head diameter: 16 mm up to 42 mm
  • inner diameter: 6 mm up to 26 mm
  • shank diameter: 10 mm up to 29 mm
  • shaft length: 10 mm up to 87 mm
  • cup-depth ratio: 0.5 up to 5.0 x cup diameter
  • inner geometry: cylindrical, square and hexagon, multi-tooth
  • hollow parts with double collar and/or undercut geometry
  • male and female threads




Parts with collapse die: thanks to this special technology of forming tools, it is possible to make geometries with undercut such as ball pins, double-collar screws and bushings, reduced-shank screws etc. even by means of cold forming without secondary cutting or subsequent processes such as     friction welding and the like. Further, the forming production process leads to a favourable stress curve inside the component which counteracts the notch effect of such geometries.

Boron-alloyed steel grades (e.g. 23MnB3), low-alloyed (e.g. 34Cr4) and alloyed steel grades (e.g. 40CrMoV4.7) as well as work-hardening and hot-hardening high-strength aluminum alloys are used as materials for forming parts. In accordance with the definite application, the material can be selected together with the customer.