Internal pressure-deformation method for hollow body, involves compressing workpiece by feed motion of plunger, increasing internal pressure, and widening workpiece in cavity under deformation pressure of specific bars

摘要

The method involves subjecting a metallic workpiece (2) to a front side within a deforming tool (1) by a plunger (8), and providing hot gas into the workpiece under pressure. The workpiece is compressed by feed motion of the plunger under internal pressure, which is smaller than deformation pressure, for deformation so as to displace material in an area of a deforming cavity (5). The internal pressure is increased, and the workpiece is widened in the cavity under the deformation pressure of more than 200 bars, where the workpiece is made of steel and a hollow body is made of metal. An independent claim is also included for a device for internal pressure-deformation of a hollow body.