All About Stretch Forming

It is a manufacturing process in which sheets of metal are stretched and bent through a die to form large, contoured pieces. The process is carried out using a stretch press where a piece of sheet metal is secured at its edges with gripping jaws.

The jaws gripping the sheet are linked to a carriage that is pulled by hydraulic or pneumatic pressure to extend the sheet. The tool employed in this process is the stretch form block, also commonly referred to as a form-die, which is a solid, contoured piece that is used to press the sheet of metal.

The stretch-forming process is an excellent method to create large edge leading edges for wing door panels, wing leading edges, and nose sections because of the lower cost of non-recurring expenses and less physical size limitations on the equipment required.

Stretch forming - OpenLearn - Open University

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Advantages of Stretch forming

Stretch forming offers numerous benefits

  • Reduces internal stress The stress is decreased due to regularised grain structures of material following heat treatment and the making process, drastically decreasing spring-back.
  • The large volume of output It is a stretch form is a fast procedure that is suitable for high volume output.
  • Big parts bigger parts can be created using the Senior Aerospace Thermal Engineering’s open-access Cold Stretch presses
  • Low cost The stretch forms are less costly than cold-draw forming, due to the use of simpler tools for forming.