Upsetting

Upsetting is a forming process in which a workpiece is shortened in its longitudinal direction by compressive forces. As the volume of the material is essentially preserved during plastic forming, the shortening results in an increase in cross-sectional area.

In cold forming, upsetting is used to distribute material in a targeted manner for further shaping or to form specific component areas directly. For example, this can be used to produce heads, flanges, collars, thickened sections or other cross-sectional enlargements.

Upsetting can be carried out as a standalone forming operation or combined as part of a multi-stage forming sequence with other processes such as forward, reverse or transverse flow pressing.

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Upsetting in cold forming
Upsetting: Questions and answers

Upsetting in cold forming

In upsetting, a workpiece is subjected to axial loading between the forming tools. The applied compressive force causes the material to undergo plastic deformation: the length of the formed area decreases, whilst its cross-section increases.

This enables, for example, heads, flanges, collars and local thickening to be produced directly from the existing material. At the same time, upsetting can be used to specifically prepare material for subsequent forming stages and to concentrate it at those points on the component where it is required for further shaping.

Controlled material distribution plays a key role in this process. The extent to which a material can be upset in a single stage depends, amongst other things, on the material, the initial geometry, the length-to-diameter ratio, the degree of forming and the tool design. For more significant changes in shape, the forming process can therefore be divided over several stages.

In multi-stage cold forming, upsetting can be combined with other forming processes. In this way, complex component geometries can be created step by step from a section of wire, without the required contours having to be produced entirely by machining.

Upsetting: Questions and answers

What does upsetting mean?

Upsetting is a forming process in which a workpiece is shortened in its longitudinal direction by compressive forces. In the process, the material is plastically displaced and the cross-section of the formed area is increased.
What geometries can be produced by upsetting?

Upsetting is particularly suitable for creating cross-sectional enlargements such as heads, flanges, collars or local thickening. The process can also be used to specifically prepare material for subsequent forming operations.
What happens to the material during upsetting?

During upsetting, the material is compressed in the axial direction. The length of the formed area decreases and the cross-section increases. The volume of the material remains approximately constant during plastic forming.
Why is upsetting often carried out in several steps?

The extent of shape change possible within a single forming stage is limited. For large changes in cross-section or complex geometries, the material can therefore be distributed across several stages. This enables controlled material flow and reliable shaping.
How does upsetting differ from extrusion?

In upsetting, the focus is on the axial shortening of the workpiece whilst simultaneously increasing its cross-section. In extrusion, by contrast, the material is specifically forced through or within shaping tool sections. In multi-stage cold forming, upsetting and various extrusion processes are frequently combined.

Upsetting

Upsetting in cold forming

Upsetting: Questions and answers

What does upsetting mean?

What geometries can be produced by upsetting?

What happens to the material during upsetting?

Why is upsetting often carried out in several steps?

How does upsetting differ from extrusion?