Abstract: This invention relates to a capsule for pressings pressed by isostatic pressure and to these pressings used for extruding metallic objects, particularly tubes, of stainless steel, the outer and inner wall of the capsule consisting of thin-walled sheet metal, and at least the outer wall having substantially the same strength properties in the axial direction over its circumference and particularly consisting of a spiral-welded tube and being preferrably provided with a bulge which is directed outwardly against the shrinkage occurring during isostatic pressing, and at least on the front end of the capsule an insert being provided, which consists of one or more pieces of a ductile solid material or a ductile material pressed from powder. The invention further relates to a process for the production of such capsules and pressings and to a process for extruding tubes and to the tubes obtained according to this process.

Abstract: This invention relates to a capsule for pressings pressed by isostatic pressure and to these pressings used for extruding metallic objects, particularly tubes, of stainless steel, the outer and inner wall of the capsule consisting of thin-walled sheet metal, and at least the outer wall having substantially the same strength properties in the axial direction along its circumference and particularly consisting of a spiral-welded tube, and preferably at least on the front end of the capsule an insert being provided, which consists of one or more pieces of a ductile solid material or a ductile material pressed from powder. The invention further relates to a process for the production of such capsules and pressings and to a process for extruding tubes and to the tubes obtained according to this process.

Abstract: A process for the after-treatment of powder-metallurgically produced extruded tubes of stainless steel or highly alloyed nickel steels, pressings initially being produced by introducing into a capsule of thin sheet steel a powder consisting predominantly of spherical particles which have been produced from the required starting material by sputtering and, after the capsule has been closed, the density of the powder is increased to at least about 80% to about 93% of the theoretical density by cold isostatic pressing and the pressings obtained are then extruded into tubes at temperatures around 1200.degree. C.

Abstract: A method and a capsule and a blank for producing tubes, bars or similar profiled elongated dense metal objects, preferably in stainless steel qualities, by single or multi-stage extrusion of capsules which are filled with powder of metals or metal alloys or mixtures thereof or with mixtures of powder of metals and/or metal alloys with ceramic powder and sealed and which are adapted in their form to the desired object or intermediate product, as starting material a powder being used which consists at least predominantly of substantially spherical grains and the capsule filled with said powder and sealed being compressed by means of cold-isostatic pressure acting all round until the density of the powder reaches at least 80% of the theoretical density.

Abstract: A long-distance heating conduit comprising one or more tubes which carry the heating medium, are laid in the conduit and are surrounded individually or jointly by at least one layer of heat-insulating material and are covered by at least one cover foil which extends in a closed path round the tube or tubes and is provided with holes.

Abstract: A method and a capsule and a blank for producing tubes, bars or similar profiled elongated dense metal objects, preferably in stainless steel qualities, by single or multi-stage extrusion of capsules which are filled with powder of metals or metal alloys or mixtures thereof or with mixtures of powder of metals and/or metal alloys with ceramic powder and sealed and which are adapted in their form to the desired object or intermediate product, as starting material a powder being used which consists at least predominantly of substantially spherical grains and the capsule filled with said powder and sealed being compressed by means of cold-isostatic pressure acting all round until the density of the powder reaches at least 80% of the theoretical density.

Abstract: A method for producing stabilized ferritic stainless chrome steels which are distinguished in the welded state by high notched bar impact strength, wherein in powder-metallurginal manner by atomizing melts of the said chrome steels under argon a powder is produced which is pressed and agglomerated in known manner and that the pressed bodies are finally brought by hot or cold working into the desired semi-finished product form, preferably sheet form.

Abstract: A mandrel, in particular a floating mandrel, for the cold drawing and/or sizing of tubes comprising a drawing portion and a shoulder portion section, wherein corresponding to the various functional requirements which are made of its different sections the mandrel consists of two or more different portions which are joined to form a resilient structure and comprise between them at least one intermediate space whose volume is variable by resilient deformation of the mandrel portions and/or relative movement of the mandrel portions with respect to each other, and is substantially completely sealable by engagement of the mandrel portions on the inner wall of the tube to be drawn.

Abstract: A method and a capsule and a blank for producing tubes, bars or similar profiled elongated dense metal objects, preferably in stainless steel qualities, by single or multi-stage extrusion of capsules which are filled with powder of metals or metal alloys or mixtures thereof or with mixtures of powder of metals and/or metal alloys with ceramic powder and sealed and which are adapted in their form to the desired object or intermediate product, as starting material a powder being used which consists at least predominantly of substantially spherical grains and the capsule filled with said powder and sealed being compressed by means of cold-isostatic pressure acting all round until the density of the powder reaches at least 80% of the theoretical density.

Abstract: A method and means of controlling the air pressure in a sound-proofed hangar in which jet engines are tested, the amount of cooling air sucked into the exhaust gas silencer by the injection action of the exhaust gas jet being adjusted by varying the flow resistance or the free flow cross-section of the area difference between the inlet cross-section of the exhaust gas silencer and the exhaust jet cross-section by inserting screens so that the pressure in the sound-proofed hangar does not drop below a predetermined value.