METHOD OF SHAPING THE PIPES AND HOLLOW PROFILES Russian patent published in 1995 - IPC

FIELD: plastic metal working. SUBSTANCE: hollow blank having flat face ends is placed in the container between the die and the press-plunger. Then the container is encapsulated by the blank deformation at the expanse of shifting the press-plunger by the value not exceeding the blank length. When container hermetic sealing is finished, the pressure of the working plasticizing liquid in it is raised by introducing the additional volume of the liquid from the autonomous source of high pressure up to the value exceeding the pressure of the pressing out. After that the blank material is extruded through the die hole. EFFECT: enhanced effectiveness of the article shaping process and reduced mass of the required equipment. 1 dwg