Allmanna Svenska Elektriska Aktiebolaget

Asea

Bertil Lundback

Jan Nilsson

Hans Gunnar Larsson

Hans Larker

Pertti Syvakari

Erik Lundblad

Sven-Goran Gustafsson

Kjell Lilja

In the hydrostatic extrusion of tubes in a press which has a pressure chamber containing a high pressure cylinder, a pressure generating portion insertable into the cylinder, a die arranged in the cylinder and a mandrel axially fixed in relation to the die and composed of a carrier portion and a tip, and in which the tip forms with the opening in the die a gap in which a tubular billet is shaped into a tube by hydrostatic extrusion, in connection with the insertion of the tubular billet, a seal is produced initially between the mandrel and the hole in the billet at a point between the front part of the mandrel carrier and the hollow wall of the billet. This may be done by producing a constriction of the front end of the hole in the billet before the mandrel is inserted therein or by upsetting the billet against the die.

Method for hydrostatic extrusion of tubes

A press for hydrostatic extrusion includes a pressure chamber for enclosing a pressure medium which is formed of a high pressure cylinder, a pressure generating piston, a die and a die support and seals. The die support includes an exchangeable support ring which engages the end surface of the liner and bridges the gap between the liner and the die. A metallic sealing ring is arranged within the liner in engagement therewith, forming a gap between the inner surface of the sealing ring and the outer surface of the die or die support. The die support has a groove in its upper surface which contains a sealing member against which the edge of the metallic sealing ring engages. The lower outer corner of the metallic sealing ring is bevelled to form a space which communicates with the outside of the press.

High pressure press

Growing community of inventors

Robertsfors, Sweden

Bertil Lundback