Abstract:
A press for hydrostatic extrusion of tubes includes a press stand with a pressure cylinder movable therein to engage over a die supported by the press stand, and a pressure-generating punch movable in the other end of the cylinder. A sleeve slidable in the cylinder supports a mandrel which can engage through an annular billet into the die opening. A billet holder is slidable in the sleeve, the mandrel passing through it. The billet holder is so constructed that pressure fluid can pass from one side of it to the other.
Abstract:
In manufacturing blades for gas turbines with a plurality of inner cooling channels by isostatic compression, a sintering capsule of deformable material is provided with thin-walled tubes arranged substantially parallel to the capsule wall parts corresponding to the high and low pressure surfaces of the blade. A powdered material is poured into the capsule, which is then evacuated, sealed and heated to at least 800*C. Thereafter the heated capsule is subjected to an external gas pressure of at least 500 bars. Simultaneously with the compression, the tubes are subjected to such a high internal gas pressure that the linear decrease in the tube cross-section is at most 50 percent.
Abstract:
A vertical furnace for treating material at high temperature and under high pressure has a stand into which a cylindrical pressure chamber is introduced. This stand is formed of a high pressure cylinder with top and bottom end closures which project into the cylinder. A furnace chamber is formed within the pressure cylinder by two hat-shaped parts with insulating material between them. These parts rest on an annular portion of the bottom closure. The inner part of the bottom closure is removable for charging the furnace.
Abstract:
A furnace for vacuum-pressure-sintering has a furnace chamber which is enclosed in and insulated from a surrounding pressure chamber. The pressure chamber includes a bottom projecting into it at the lower end and has at the upper end a charging opening and a lid projecting into the charging opening. A housing can be applied over the charging opening and connected to a vacuum pump during the part of the operating cycle when the pressure in the furnace is to be below atmospheric pressure. The lid is formed of an outer annular part and an inner part, separate from each other, the outer annular part remaining in position when the inner part is removed. A heat radiation protection ring is provided for insertion into the opening into the annular part when the annular part is raised. A lifting device for the lid is provided inside the housing.
Abstract:
In a cylindrical elongated furnace for treating material at high temperature in a gaseous atmosphere under high pressure, the furnace chamber is insulated from the walls of the pressure chamber by at least three tubular parts arranged one inside the other with insulating parts. At least one ring is provided attached to one of the tubular parts and having a downwardly and inwardly sloping similar part secured to the inside of this part and directed towards, but terminating short of, the opposed part.
Abstract:
A cylindrical elongated furnace for treating material at high temperature in a gaseous atmosphere under high pressure is formed of a high pressure cylinder with end closures projecting into it and a furnace chamber arranged in the high pressure cylinder. The furnace chamber is insulated from the walls of the pressure chamber by a cylindrical casing having gas-impermeable tubes arranged one inside the other with an insulation between them. At least one layer of insulating material in the casing engages only the outer or inner surface of one tube and is spaced from the adjoining tube, the space between being filled with gas. The insulating material may be held against the outside of one of the tubes by rings or a spiral strip running helically.
Abstract:
A cylindrical elongated electric furnace placed in a pressure chamber for isostatic compression with its longitudinal axis substantially vertical. A heat-insulating mantle is provided for thermal isolation of the hot furnace chamber from the walls of the pressure chamber. This mantle is constructed of thin sheet metal arranged on a tubular frame and is free from insulating material of ceramic type. The sheet metal forms a plurality of cylindrical or conical layers located radially one outside the other and having gas-filled spaces between them.
Abstract:
A vertical furnace for isostatic hot-pressing of powder bodies includes a cylindrical pressure chamber formed of a high pressure cylinder and end closures projecting into the cylinder. Insulation arranged in the chamber includes a cylindrical insulating wall and end insulation members. There is a seal between the upper end closure and the high pressure cylinder. In order to protect this seal against heat from the inside of the chamber, a heat resistant seal of a semi-porous material such as asbestos is arranged below the first seal in the space between the pressure cylinder and the upper end closure projecting into the cylinder.