Abstract: A mounting ring of synthetic material for fitting two pipe sections in place relative to each other, has a radial flange (1) and an axial neck (2). Tongues (3, 4, 5, 6) of differing lengths extend radially inwardly and radially outwardly from the neck. These tongues are preferably formed as part of the ring, for example, when molding the ring of synthetic material. The longer radially outer tongues bend over, snap into a groove, and center the ring in a pipe socket. The shorter radially outer tongues support the ring in the socket. When a pipe end is inserted into the socket through the ring the longer radially inner tongues bend and center the pipe in the socket while the shorter radially inner tongues support the pipe end. Thus, the inner surfaces of the pipe sections remain in alignment with each other because the shorter tongues act like spokes against forces acting crosswise on the pipe sections relative to their length.

Abstract: A stress relaxation characteristic of an elastomeric material such as rubber and other elastomers under pressure is established by determining the ratio of the difference between two forces acting on a test sample before and after the test sample is stored under compression, to the force acting on the test sample before the sample is stored under compression. First the sample is subjected to an initial deformation, whereby its initial thickness is reduced by 23-27%. Subsequent deformations then amount to not more than 0.05 mm. In order to achieve these quantitatively very small subsequent deformations, the sample is permitted to expand rather than being subjected to additional compressions. Maintaining the exact magnitude of these subsequent deformations in the form of expansions as well as carrying out accurate force measurements is much simpler than causing additional compressive deformations and measuring the respective forces.

Abstract: An endless conveyer or drive belt reaches with a portion of its cross-sectional configuration facing toward respective guide or drive rollers, into corresponding ring grooves in the rollers. The projecting portion includes an endless helical spring partially embedded in the drive belt. The ends of the helical spring are connected to each other. The spring keeps the belt trained on the rollers.

Abstract: A transport roller, especially for transporting sheet material such as sheets of paper, has a rigid core surrounded by a friction increasing jacket of elastic material. At least one member is inserted between the jacket and the roller for preventing a relative axial displacement between the core and the jacket. Such member is an endless helical spring partially embedded in the jacket and projecting into a ring groove in the core, whereby the jacket is firmly held in place on the core against any relative axial displacement.

Abstract: In order to produce a packing ring having a stiffening ring by a method which dispenses with the use of a complicated and expensive mold, an extrusion having the desired cross-section of the packing ring and having a cavity, extending in the extrusion direction, for the reception of the stiffening ring is firstly produced. The extruded material cut to length in accordance with the desired circumference of the packing ring is slipped onto a wire which is similarly cut to length and bent into a circle. The ends of the extruded material are pushed back while the ends of the wire are welded together, so that a closed stiffening ring is produced. Then the material ends are joined together and are bonded or vulcanized to one another.

Abstract: A sealing device for a pipe connection requires tighty clamping a sealing ring (1') made of elastomeric material in a socket and of a pipe section for the subsequent insertion of a plug-in end of an adjacent pipe section. An endless expanding ring (2) made of steel is held in an inwardly facing groove and butts in a gap-less manner against the base or bottom surface of an inwardly open groove (3) in the sealing ring (1'). The expanding ring (2) of steel is deformed by radially outwardly forces to increase the diameter of the steel ring slightly beyond the elastic limit of the steel of which the ring (2) is made. Thus, the circular outer periphery of the steel ring is still maintained even after the radially outwardly directed forces are removed, whereby the sealing device is locked in the socket against undesired displacement of the sealing ring (1').

Abstract: A seal for use with pipes to be inserted one into another with spigot and socket ends, comprising a sealing sleeve made of an elastomeric material and arranged in the socket, wherein the sleeve is provided with a radially resilient element, the arrangement being such that, after being mounted in the socket, the seal is clamped in the socket by the radial resilience of said element.

Abstract: A shaft with rubber rollers designed to be made in a simple and inexpensive manner. The rollers are made separately with a helical spring or split clamping sleeve vulcanized in them during manufacture. The required number of rollers are ground to size and placed in an assembly block in the required spaced and axially aligned relationship, and the shaft is forced through the central apertures of the rollers.

Abstract: A seal for use with pipes to be inserted one into another with spigot and socket ends, comprising a sealing sleeve made of an elastomeric material and arranged in the socket, wherein the sleeve is provided with a radially resilient element, the arrangement being such that, after being mounted in the socket, the seal is clamped in the socket by the radial resilience of said element.