Swaging Press

The Swage machine, also called an Autofrettage, is a manufacturing process used to strengthen high-pressure gun barrels primarily used in artillery cannons. The main goal is to increase the barrel’s resistance to internal pressures during firing and to extend its service life.

What is Autofrettage?

Autofrettage is a cold working process where the inner portion of a thick-walled cylinder is subjected to internal pressure high enough to plastically deform the inner layers of the barrel while the outer layers remain elastic. After the pressure is removed, the outer elastic layers compress the inner plastic layers, putting them in a state of residual compressive stress.

Benefits of Autofrettage:

• Improved fatigue life – The residual compressive stress counters the tensile stress created when the gun is fired.
• Increased pressure limits – The barrel can withstand higher internal pressures without yielding.
• Improved safety – Reduces the risk of barrel rupture or fatigue cracks.