Asea Aktiebolag

Allmanna Svenska Elektriska Aktiebolaget

Hans Gunnar Larsson

Erik Westman

Jan Nilsson

Pertti Syvakari

Bertil Lundback

Sven-Goran Gustafsson

Carl Bergman

Kjell Lilja

An apparatus for granulating a metal melt which comprises a closed housing having a granulating section and a collecting section for the collection of manufactured powder, the granulating including a casting box and one or more primary nozzles which form decomposing, groove-shaped gas jets which impinge against the stream of metal melt falling from the casting box to form droplets which are then thrown in a parabolic trajectory into the collecting section. The apparatus further includes one or more secondary nozzles producing one or more auxiliary gas jets which are used to increase the breakdown or granulating effect of the groove-shaped gas jets, to control the trajectory of the formed droplets in the collecting section of the housing and to prevent the eddying of the formed droplets towards the primary nozzles from which the groove-shaped gas jets emanate.

Apparatus for manufacturing a metal powder by granulation of a metal melt

A method for granulating a metal melt wherein a tap stream of molten metal is granulated by directing a jet of gas having a trough-shaped cross-section against the side of the tap stream such that the tap stream is formed into droplets which are thrown into a parabolic trajectory. An additional gas jet is also directed towards the tap stream so that it hits both the trough-shaped gas jet and the tap stream, the additional gas jet acting to prevent the droplets of metal melt from moving towards the nozzle from which the trough-shaped jet of gas emanates. The nozzle which emits the trough-shaped jet of gas can thus be positioned very closely to the side of the tap stream without becoming clogged with deposited droplets of metal melt.

Method for manufacturing a metal powder by granulation of a metal melt

A method for manufacturing billets intended to be subsequently machined into a desired shape by plastic deformation, as by rolling, includes the heating to a predetermined bonding temperature of powder grains enclosed in a capsule, and subjecting the capsule at the bonding temperature to a high pressure sufficient to bond the powder grains together to form a substantially solid body. The capsule is inserted at the bonding temperature into an over-sized forming cavity of a press which includes relatively movable punches, the capsule being completely surrounded within the press by a layer of heat-insulating and pressure-transmitting solid material, such as talc or the like. Thus, when the capsule is subjected to the high pressure upon operation of the press, such material serves as a pressure-transmitting medium through which pressure is applied completely against all sides of the capsule.

Method for manufacturing billets, from metal powder, intended to be

In a press for hydrostatic extrusion, the die has a conical inlet portion and a portion forming a die opening. The die has draining channels which bypass the smallest cross-section of the die opening for the purpose of intercepting and diverting pressure medium which accompanies the billet as it moves down towards the smallest cross-section of the die. This removes any pressure medium which might otherwise pass through the die opening and damage the surface of the extruded article.

Hydrostatic extrusion press

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

A compound billet for extrusion by isostatic liquid pressure which has a core and a casing with a gap therebetween is produced by applying a sealing ring with greater thickness than the gap between the core and the casing around the rear end of the core, then inserting the core into the casing, and pressing the sealing ring to stick in the gap between the core and the casing so that the sealing ring and/or the casing are deformed. The rear end of the casing is beveled inwardly.

Method for hydrostatic extrusion

In isostatic hot pressing of powder in a collapsible container, the powder is enclosed in a container which is provided with one or more evacuation openings, and a conical support is held in position adjacent the evacuation openings. A funnel-shaped body of sheet metal is secured above the support and the evacuation openings by welding its edge to the wall of the container. The body is evacuated through a suction tube connected to the funnel and the tube is sealed. Thereafter the container is subjected to heat and pressure, and the funnel-shaped member collapses into engagement with the conical support.

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Vasteras, Sweden

Hans Gunnar Larsson