Abstract: A branch piece for pipe-lines comprising a first part and a second part for forming a cylindrical housing, each of the two parts being provided with a coupling edge for engaging a connecting or closing part. The parts are provided with wedge-shaped tongues which fit in complementary wedge-shaped recesses in the other parts.

Abstract: A pipe having a sealing member (3) in an inner groove (2) at one pipe end (1). The sealing member provides a very effective seal relative to a spigot end (1a) of another pipe inserted in the pipe in question. The free ends of lip portions (6,7) of a sealing ring (4) (the cross section of which is of V-shape when undeformed) are provided with beads (8) so that behind a stiffening ring (5) surrounding said sealing ring (4) there is more volume of lip material than there is room for in the space confined by the adjacent part of the bottom of the groove (2), the exterior (1a') of said spigot end (1a), the rearmost sidewall (2') of the groove (2) and the stiffening ring (5). The pipe is preferably a plastic pipe.

Abstract: A tray for packaging fruit comprising a base and converging side walls, is provided with a wide rim at its upper side, said rim being integral with a suspending ledge, while a support can be pushed through an opening in the rim at the corners of the tray and a staggered part of the support fits the ledge, the support also being fixed by cams at the base of the tray.

Abstract: A method of manufacturing a fiber reinforced plastic pipe part, comprising a first wall part and a wall part adjoining the latter through an inner rounded corner transition having a radius of curvature of less than 5 mm, preferably 0,5 to 3 mm.

Abstract: A plastic well pipe comprising an outer wall, an inner wall, and channels formed by longitudinally extending partitions being integral with the walls, the outer wall being provided with bores opening into the channels, while at certain points the inner wall has been removed for recovering liquid from the channels, which liquid flows into the channels through the bores.

Abstract: A composite tubular assembly comprising a membrane for membrane filtration fixed to the inner side of a tube of non woven material, consisting of a wound band of a sealable fibres containing non woven material, which may be helically or non helically wound, consecutive overlapping windings of the band being completely interconnected by ultrasonic heatsealing and thereby forming a smooth inner wall of the tube.

Abstract: Thermoplastic tube part provided with a polyurethan foam layer with closed skin and containing an inorganic filler for reducing sound production during flow of water through such tube parts.

Abstract: A plastic pipe of a thermoplastic material, such as polyvinylchloride provided on its outside with a resilient sealing body of a polyurethane foam plastic, which has been foamed onto said outside and a layer of thermosetting resin with electrically conducting particles being between said body and the plastic pipe in order to ensure a proper conduction, the foam plastic body having a closed surface being integral with the foam plastic body.

Abstract: A heat sealed or welded pipe connection for thermoplastic pipes comprises a male pipe part which is sealed to the inner surface of a female pipe part, said female pipe part carrying centering abutment projections on its outer surface. The female pipe part may consist of a socket which starting from its openings has an outer circumference with an increasing size, the outside radius of curvature of the socket is 6 to 12 times the outside diameter of the male pipe part and the total length of the socket is equal to the outside diameter of the male pipe part.

Abstract: A tube of thermoplastic material is heated to plasticity, whereupon the heated tube is provided with a thickened end by subjecting the tube to an upsetting action in such a way that the thickening starts at a distance from the free end of the heated part and increases gradually from this point towards the free end of the heated part.

Abstract: Sealing member for a spigot and socket coupling, comprising a retaining part, a sealing part extending with two steps within the space bound by the inner circumference of the retaining part and of the extension thereof and a connecting part interconnecting the retaining part and the sealing sleeve. At any point between the junction with the retaining part and the free end of the sealing sleeve, the thickness of the sealing member is not greater than the thickness of the part extending between said point and said junction. The thickness does not exceed the thickness of the sealing member at said junction.The inner side of the steps of the sealing member are provided with leakage-preventing ribs and the retaining part is substantially perpendicular to the connecting part, whilst the first step of the sealing sleeve is situated within the inner side of the retaining part. The end of the sleeve is provided with a tapered lip forming preferably a sort of sickle with the sealing member.

Abstract: A device for manufacturing a plastic tube having a thickened socket end and being provided with an inner circular groove. The device includes a socket forming mandril having a core member associated with it. The mandril is provided with a groove-forming member. A hollow die is also provided which has a portion adapted to fittingly cooperate with the outer side of the mandril. A hollow mould lies in an adjoining relationship with the hollow die and is disposed in front of the core member. The hollow mould has an inner diameter which is greater than the outer diameter of the mandril.

Abstract: A conducting plastic pipe system comprising a male plastic pipe part and a female plastic pipe part with conducting covering layers which are interconnected by means of a conducting sealing ring between the male and female part. In case of outer covering layers on the pipe part the covering layer extends onto the inner side of the muff end of the female pipe part.

Abstract: A pipe having an outer coating of foam plastics, a tape of thermoplastics being wrapped around the foam plastics in an overlapping way, the overlapping parts being heatsealed to each other. At least one reinforcing filament is present on the original contacting surfaces of the overlaps. Preferably one straight and one zig-zag applied filament are present.

Abstract: A process for perforating plastic tubes, in particular thin-walled corrugated tubes, by a punching or cutting operation wherein the plastic tubes are subjected to a direct or indirect treatment by a cooling fluid prior to the punching and cutting operation. The process is performed by an apparatus comprising a guide structure and conveying device for conveying the plastic tubes, and further comprising punching or cutting members, while spraying devices are provided for effecting the above-mentioned cooling treatment.

Abstract: A branch piece for pipe branch connections comprising two parts. The first part is provided with two longitudinal edges extending parallel to the axis of the branch pipe, and the other part is provided with one longitudinal edge which can be coupled with one of the longitudinal edges of the first part. The second longitudinal edge of the other part tapered. A separate wedgelike connecting member has two lips each adapted to engage with a longitudinal edge of the first part and of the second part.

Abstract: A method for manufacturing perforated plastic pipes, in particular corrugated thermoplastic pipes of which the wave valleys are perforated by at least one punching member, to which a velocity is imparted in the direction of conveyance of the plastic pipes, which equals the rate of conveyance of these pipes. During the punching operation the punching member or members retain substantially a perpendicular position with respect to the plastic pipes.

Abstract: A thermally insulated pipe particularly destined for mining industries, comprising an outer and an inner pipe, whereinbetween an insulating layer is arranged, the outer pipe being made of a synthetic material. The surface of the outer pipe is provided with an outside surface layer, being electrically conductive, which layer is connected with the inner pipe in an electrically conducting manner. The insulating material inbetween the two pipes is heat resistant.

Abstract: Plastic bags are obtained from a tubular foil of thermoplastics by means of heatsealing. The heatsealing member acts upon a lower wall of the flattened non-tensioned tubular foil, and without a counter pressure to the upper wall of the foil. The entire thickness of the lower wall is plasticized but only a portion of the thickness of the upper wall is plasticized. The assembly of heated lower wall and partly heated upper wall facing each other is passed through two pressure rolls, the roller surface contacting the surface which has not been in contact with the heat sealing member consisting of metal is cooled.