Backward Extrusion – Hollow Shapes With Precision and Stability

Backward extrusion is a cold bulk forming process used to produce hollow components with high dimensional accuracy and consistent wall thickness. In this process, the material flows opposite to the direction of the punch, enabling very controlled shaping and excellent material distribution. Walter Schneider uses this process to manufacture high-precision serial components for clients in mechanical engineering, medical technology, electrical engineering, and more.

What happens during backward extrusion?

In backward extrusion, a blank is placed into a die. A punch presses into the blank, causing the material to flow in the opposite direction—into the space between punch and die—forming the hollow geometry.

Technical Features

Material flow opposite to the punch movement
Cold forming at room temperature
Chipless forming – almost 100% material utilization
Excellent dimensional accuracy and smooth internal surfaces
Suitable for uniform or variable wall thicknesses

This process is particularly suitable for components with internal cavities, smooth inner contours, or thin-walled structures that need to be strong and robust.

Typical Components for Backward Extrusion

Sleeves and bushings
Cup or cap shapes with internal geometry
Hollow cylinders for electrical connectors
Tubular segments or sealing components
Hollow parts for medical devices or sensor housings

Your Advantages With Backward Extrusion

High Dimensional Accuracy in Hollow Components

The process allows for very controlled wall thickness distribution – ideal for rotationally symmetrical precision parts with an internal contour.

Smooth Internal Surfaces – Minimal Post-Processing

The flowing material behavior results in especially uniform, dense surfaces – often without additional processing steps.

Work Hardening for Higher Strength

The forming process compacts the material and improves the mechanical load capacity of the component – without heat treatment.

Cost-Efficient for High Volumes

Automated processes and durable tools make backward extrusion particularly attractive for serial production starting at approximately 50,000 pieces.

Combinable with Forward and Lateral Extrusion

Complex geometries with various forming directions can be efficiently manufactured in a single process.

Materials Suitable for Backward Extrusion

Walter Schneider processes a wide range of metallic materials – including demanding alloys:

Stainless steel – for durable, corrosion-resistant parts

Aluminium – light, malleable, and ideal for thin-walled hollow bodies

Copper & lead-free copper alloys – for electrical applications

Special materials – for specific strength or temperature resistance requirements

Walter Schneider GmbH: Your Specialist for Backward Extrusion

With decades of experience in extrusion technology, we offer:

Technical consultation & feasibility assessment
Own tool development and production
Backward, forward, and lateral extrusion – also combined
Serial production with CAQ-supported quality assurance
Complete solutions including subsequent processes like vibratory finishing or heat treatment

Are you planning a hollow-shaped component?

Whether it’s a sleeve, bushing, or cup-shaped component – we will provide a non-binding assessment to determine if backward extrusion is the right solution for your application.