Abstract: A casting furnace is fed an inert gas under pressure through a feed line with the pressure being regulated by a melt level control device. When the pressure is reduced, the inert gas is exhausted from the casting furnace by an exhaust line, the feed line having a check valve to prevent gas which is contaminated by magnesium from entering the feed line. An oxidizing gas, preferably pressurized air, is periodically fed into the exhaust line by an oxidizing gas line for cleaning the drain line and the pressure-controlling aperture therein by oxidizing the magnesium.

Abstract: In a closed system a shock pressure wave of a burning gas is used for packing granular mold material loosely distributed around a model. Before the shock pressure is produced, the pore volume of the upper layer of the granular material exposed to the pressure is reduced. Through the pore volume reduction, the active surface of the granular material is increased, so that the gas pressure acts on an increased working surface and, consequently, greater mold hardness is achieved.

Abstract: A method of compacting particulate material includes providing a primary fuel mixture of air and natural gas in a closed chamber enclosing a surface of the material to be compacted. An additive gas, such as hydrogen, having a higher combustion velocity is added to the primary fuel/air mix and ignited, creating an exothermic reaction which compacts the material. The additive gas increases the gradient of the pressure rise curve of the combustion. Various fuels and additive gases and disclosed.

Abstract: A permanent mold is equipped with a core pulling device covered with a thin sand jacket, that can be peeled off, in order to produce unregular caves in the cast.

Abstract: A one-piece, cast vehicle wheel rim for tubeless tires comprises a rim portion and a supporting ring extending from the rim portion. The rim portion has a drop center portion between first and second side walls. The support ring mounts the rim on a disc and has a recess between its end areas. A valve hole is formed in the first side wall of the rim portion adjacent the recess for mounting a valve such that the valve extends into the recess. Radially extending ribs can connect a shoulder of the rim portion to the end areas of the support ring on opposite sides of the valve hole. The ribs can be angularly oriented toward each other in a radially outward direction and can be spaced from the valve hole by a distance between about 15 mm and about 30 mm. When used in combination with another rim to form dual wheels, a coupling on the support ring attaches the rims. The coupling and recess permit the valve to be exposed for ready access.

Abstract: A welded joint for plastic pipe is formed by apparatus including a sleeve (6) which is placed over the place where the pipes are joined and a heating mat (3) which is inserted between the sleeve and the pipes. The heating mat (3) and the sleeve (6) are provided with gear-tooth system (4, 5, 114, 115) which engage each other in the assembled condition of the device. Consequently, the surfaces of the ends of the heating mat (3) and the sleeve (6) which are in contact are circumferentially extended, resulting in a satisfactory welded joint, even where large pipe tolerances are involved.

Abstract: A vehicle wheel rim has a tire-engaging rim portion with two conical portions, one of which lies radially outwardly of a support ring having a conical surface for mounting the rim on a spider or the like. The outer ends of the conical portions terminate at tips and a drop center lies between the conical portions. A radial crosspiece extends from the support ring to about the center of the conical portion outside the support ring. The rim is cast in a mold having two mold halves and an annular core member defining the outer rim surface.

Abstract: An apparatus for cutting and threading pipe comprising a portable support frame formed by disengagable members, cutting and threading units mounted on the frame and a pipe clamp fixed to the frame between the cutting and threading units. The cutting and threading units have separate drive motors. The threading unit is slidably and rotatably mounted on a guide pipe for pivotal movement between operative and inoperative positions and for axial movement toward and away from the cutting unit during threading operations. The pipe clamp non-rotatably holds the pipe during the cutting and threading operations and extends the entire distance between the cutting and threading units when located closest to one another.

Abstract: A cast, one-piece vehicle wheel is made such that the wheel pan with hand-holes passing through it is fastened to the rim such that the intermediate parts of the pan abut on the shoulder, which is formed on the side adjacent the offset wheel pan, and the shoulder extends by lobes in the direction of the drop-center. In the areas of the rim corresponding to hand-holes 10, the shoulders extends over inclined elements into the drop-center.

Abstract: A process for compacting moulding sand to form a casting mould comprises the steps of filling a moulding space located between a pattern plate and a pressure plate with moulding sand, pre-compacting the moulding sand, after the moulding space is filled with moulding sand and closed by the pressure plate, by an explosive-type shock pressure, and subsequently re-compacting the moulding sand by mechanically pressing the moulding sand between the pattern plate and the pressure plate.

Abstract: A butterfly valve includes a gasket on the pivotable member which has a peripheral ring portion and two end rings which are concentric to the shaft supporting the pivotable member, each end ring having a flange held under spring pressure between the pivotable member and bushings on the shaft ends. The gasket thus seals the valve against leakage to the outside and to the shaft.