Combined Extrusion

Combined Extrusion combines different extrusion principles within a single forming process. In this process, the material can flow simultaneously or selectively in different directions to form multiple geometric areas of a component.

For example, elements of Forward, Reverse and Cross-Flow Extrusion can be combined. This enables the production of complex component geometries that could not be produced with just one direction of material flow, or only with additional manufacturing steps.

In cold forming, combined extrusion enables targeted material distribution and can help to produce complex geometries with high material utilisation.

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Combined Extrusion in cold forming
Combined Extrusion: Questions and answers

Combined Extrusion in cold forming

In combined flow forming, the material is guided in such a way that multiple directions of material flow can occur within a single forming operation. Depending on the tool and component geometry, material can, for example, flow simultaneously in the direction of and against the punch movement, or additionally in a radial direction.

This allows different areas of the component to be formed simultaneously. For example, external contours, hollow areas, steps, flanges, collars or other geometric features can be produced within a coordinated forming sequence.

Combined extrusion offers particular advantages for complex components. Instead of producing individual geometries through separate manufacturing operations or subsequent machining, several geometric features can be created during the forming process itself. This can reduce material usage, processing effort and the number of manufacturing steps required.

At the same time, the design of the process places high demands on the control of material flow. The material, degree of forming, tool geometry, friction conditions and forming forces must all be coordinated. For complex components, Finite Element Simulations can help to analyse material flow and tool loading as early as the process development stage.

Combined Extrusion: Questions and answers

What is Combined Extrusion?

Combined Extrusion refers to the combination of different extrusion principles within a single forming process. The material can flow in multiple directions to shape different areas of a component simultaneously or in a coordinated manner.
Which flow forming processes can be combined with one another?

Depending on the component geometry, forward, reverse and transverse extrusion in particular can be combined. The combination used depends on the desired geometry and the required material distribution.
What geometries can be produced using Combined Extrusion?

The process is suitable for complex components with different shaped geometric elements. These may include, for example, stepped outer contours, hollow areas, flanges, shoulders, steps and other functional geometries. The specific manufacturability depends, amongst other things, on the material, component geometry and degree of forming.
What are the advantages of Combined Extrusion?

By combining different directions of material flow, multiple geometric features can be created through forming. This makes it possible, for suitable components, to reduce the need for additional manufacturing operations, achieve high material utilisation and produce complex geometries cost-effectively in series production.
Why is process design particularly important in Combined Extrusion?

As the material flows in different directions, material distribution, forming forces and tool loads must be specifically coordinated. For complex components, forming simulations can be used to analyse the material flow even before the tool is manufactured and to design the process accordingly.

Combined Extrusion

Combined Extrusion in cold forming

Combined Extrusion: Questions and answers

What is Combined Extrusion?

Which flow forming processes can be combined with one another?

What geometries can be produced using Combined Extrusion?

What are the advantages of Combined Extrusion?

Why is process design particularly important in Combined Extrusion?