Abstract: A throttle device, especially a throttle valve, is a throttle cage which is a composite of at least two or three layers including an engineering ceramic layer and at least one metal sleeve. In a two-layer embodiment the ceramic is provided on the upstream side and the metal sleeve on the downstream side. In a three-layer configuration the ceramic layer is sandwiched between metal sleeves. The throttle device is particularly adapted to take up shock stresses and alternating stresses namely temperature and or pressure stresses, and also provides the requisite resistance to corrosion, abrasive action, cavitation and the like to materially increase the useful life of the throttle body.

Abstract: A ball cock for fluids carrying abrasive materials has its inlet passage terminating with a smaller cross section than the mouth of a ball passage which, in turn, has a smaller cross section than the mouth of the outlet passage aligned therewith. The cross sectional differences exceed manufacturing and assembly tolerances and have been found to minimize wear of the ball cock.

Abstract: An assembly of a first expansion stretch, a first throttle, a second throe and a second expansion stretch have respective metal casings and elements defining the flow paths therein composed of engineered ceramics. The throttle are adjustable and the assembly can be used effectively to control pressure and flow rate of compressible or incompressible fluids which can have solid particles entrained therein.

Abstract: A valve has a housing having an inlet connection and an outlet connection d formed with a valve seat having spaced inlet and outlet ports connected to the respective connections and a valve element formed with a throughgoing passage having an upstream end and a downstream end. This valve element fits in the seat and is displaceable therein between an open position with its passage aligned between the respective inlet and outlet ports and a closed position with its passage out of alignment between the ports. The passage is formed upstream of its downstream end and downstream of its upstream end as a restriction and is of larger flow cross section at its downstream end than at the restriction so that on fluid flow through the valve from the inlet to the outlet pressure drops in the passage downstream of the restriction.

Abstract: A method of making a joint implant prosthesis which has a shaft adapted to fit into the bone cavity of a tubular bone and having a core region and a shaft region. The geometry of the bone cavity is determined by an irradiation method and based upon the detected geometry, the shaft is dimensioned. First a geometric centroid axis of the bone passage is determined and then the core region built up by computer around this axis with the aid of finite element analysis based upon geometry of the bone cavity. The boundary conditions of an undercut-free shaft and uniform distribution of the normal stresses in the shaft bone transition region are observed. The second boundary condition is also used as a control in the coating of the core with synthetic bone material and in the configuration of the surface region.

Abstract: A pipe section of an outer metallic pipe and a nonmetallic inner lining is provided so that the lining can be removed. To this end, the lining consists of lining segments, the terminal members of which are braced against the ends of the pipe in a form fitting manner and the successive lining segments can interfit with, for example, complementary frustoconical formations.

Abstract: A joint prosthesis, especially for a hip joint has a metal shaft receivable in the marrow cavity of the bone, a closure plate at the upper end of the shaft, and a formation adapted to form the ball joint. The underside of the plate and the shaft along its length are provided with a layer of synthetic bone material which is of greater thickness in the region of the plate and adjoining the plate, corresponding to the greater stress region of the bone, than along the shank remote from the plate.

Abstract: A pipe section of an outer metallic pipe and a nonmetallic inner lining is provided so that the lining can be removed. To this end, the lining consists of lining segments, the terminal members of which are braced against the ends of the pipe in a form fitting manner and the successive lining segments can interfit with, for example, complementary frustoconical formations.

Abstract: A valve in which the movable valve member, e.g. a ball or slider, has at st one valve seat braced thereagainst and is composed of an engineering ceramic which differs from the engineering ceramic of the valve seat with the two ceramics being paired to reduce adhesion between them. One of the ceramics can be an oxide ceramic while the other is a nitride or carbide ceramic or one can be a nitride ceramic while the other is a carbide ceramic.

Abstract: A joint prosthesis, especially for a hip joint has a metal shaft receivable in the marrow cavity of the bone, a closure plate at the upper end of the shaft, and a formation adapted to form the ball joint. The underside of the plate and the shaft along its length are provided with a layer of synthetic bone material which is of greater thickness in the region of the plate and adjoining the plate, corresponding to the greater stress region of the bone, than along the shank remote from the plate.

Abstract: A joint prosthesis insertable, for example, in the marrow cavity of the femur, has a shaft formed with three longitudinally extending angularly equispaced contact surfaces by reason of a triangular of Y section. A statically determinate engagement of the prosthesis shaft in the bone is thus obtained.

Abstract: A flow-setting valve has a housing, a flow-guiding duct, a ceramic valve ball and a flow-regulating spindle. The flow-regulating spindle has a plurality of form-fitting elements fitting in complementary receptacles of the valve ball. At least the valve ball is made of an engineering ceramic material. The form-fitting elements are located in the vicinity of the outer edge of a disk which is connected with the flow-regulating spindle. The diameter of the disk is approximately half the diameter of the valve ball.

Abstract: A controlling valve, especially a valve ball, for a gaseous and liquid flow material, comprises a housing, two connector pipes, a flow-adjusting component and associated valve seat components. The flow-adjusting component and the valve seat components have corresponding flow ducts, which are provided in a special component made from sintered ceramic material. At least the flow duct of the flow-adjusting component is located in a sintered ceramic sleeve. This sleeve is inserted in a passage in the flow-adjusting component and pressure-relieved in regard to material flow. The sleeve is held under frictional forces or just fits in the passage.

Abstract: A forged piston blank for a forged piston of an internal combustion engine is formed with undercuts between the eye portions and crown side or head portions of the ears so that a larger piston pin may be accommodated by virtue of the fact that the wall thickness at the upper portion of the eye is greater than the wall thickness of the head portion of the ear.

Abstract: Our invention is a three-way valve including a pressure-tight housing, a ve seat, a closing member mounted movable in the valve seat and an operating member guided through a shaft seal. The housing is formed with three connecting channels and the valve seat with associated connecting passages. The closing member has a metering passage by which two of the connecting channels are connectable alternately with a third channel with connecting passages intervening. In an additional controlling position the closing member seals the connecting channels. Our invention is characterized by a closing member formed like a sliding plate and the valve seat has two sealing disks between which the sliding plate is positioned moveable up and down. The sealing disks are equipped with the connecting passages and at least one of the sealing disks has its connecting passages in a controlling spacing which is larger than the diameter of the metering passage in the sliding plate.

Abstract: The ball valve according to my invention comprises a pressure-tight housing ith at least one inlet-side and at least one outlet-side connecting pipe element, a valve ball made of sintered ceramic material, a valve seat and an operating shaft connected to the ball valve and guide through a shaft seal of the housing. The valve seat comprises seat rings which are clamped between the connecting pipe elements sealing the housing and are compressed on the valve ball. According to my invention the inlet-side seat ring placed on the inlet-side connecting pipe element is made of a flexible sealing material and the outlet-side seat ring put on the outlet-side connecting pipe element comprises a sintered ceramic ring which is inserted in the housing with a sealing element interposed and is resiliently supported on the outlet-side connecting pipe element.

Abstract: The connector pipe segment for conductor pipes or conduits for gaseous as well as fluid flow media comprises a pressure-tight outer shell, at least two connector pieces, a plurality of sealing surfaces and a wear-resistant sleeve, advantageously of a sintered ceramic material. The wear-resistant sleeve is inserted in the outer shell and the sealing surfaces are located on the outer shell. The wear-resistant sleeve is inserted with radial play and with axial play free of force in the outer shell so that a gap is formed between the outer shell and the wear-resistant sleeve. The gap is connected with the open cross section of the wear-resistant sleeve and admits the flow media.

Abstract: The ball valve, especially for a solvent-containing flow and/or an abrasive solid mixture, has a housing, a sintered ceramic valve seat, a sintered ceramic valve ball and an operating shaft for the valve ball guided through a shaft seal in the housing. The valve ball is positioned free of an elastic seal between seating surfaces of the valve seat and the valve seat has at least two sintered ceramic seat rings which are mounted in the housing and which are acted on with a pressing force by an elastic element supported in the housing. The valve ball is positioned between the seat rings which seal on the housing and are acted on with a sealing force. The seat rings have a plurality of seating surfaces which are formed like the surface of an inner core and contact tangentially on the valve ball along circumferential sealing lines.

Abstract: A ball cock having sinter ceramic valve ball and seat rings, also has wear-resistant bushings between the pipe connectors joined to the ends of the housing sleeve and the seat rings. Compressible seals bearing upon the bushings and clamped between the bushings and the pipe connectors press the bushings against the seat rings and the seat rings against the valve ball.

Abstract: Tensioning elements for construction purposes comprising reinforcing rod for prestressing concrete can be fabricated from steel of the following composition:0.7 to 1.0% by weight Mn0.7 to 2.2% by weight Cr0.3 to 0.6% by weight Mo0.5 to 2.2% by weight Niup to 0.45% by weight C (preferably at least 0.1% by weight C.)balance iron and unavoidable steel impuritieswhich is subjected to austenitization, oil quenching and optional tempering to a tensile strength of 1400 to 2000 N/mm.sup.2 and an elongation to break in excess of 7% and preferably about 10% and is welded to a terminal element of the same composition but having a tensile strength substantially 10-20% less than that of the rod, and then incorporated into a concrete structure.