A system that uses the male-female coupling concept, by mechanical interference between the serrated toothing on the parts to be fastened permanently together or by way of a sleeve-like couplings, but not before sealing elements which satisfy the IP 68 rating are placed therebetween. The outermost, female part or the sleeve-like couplings have particularly elastic peripheral ribs which allow them to expand sufficiently to fit the serrated toothing, such that the mounting can only be undone by cutting the rib, thus characterizing the violation of the sleeve-like coupling or of the outermost female part having a complex profile, used in the fastening system.

An insulating insert is positioned around a field joint of a pipeline to insulate the field joint. The insert includes a longitudinal series of annular or part-annular filler segments of insulating material, curved about a longitudinal axis, that are each joined to one or more adjacent segments of the series by at least one link. The links may be webs, rods or articulated links. The links are flexible relative to the segments to facilitate bending of the insert along its length by enabling relative angular displacement between adjacent segments of the series.

A joined body is formed by joining end surfaces of two joining members to each other by a friction welding. The joined body includes a hollow portion formed on at least one of the two joining members, the hollow portion being configured to have an opening at the joining face between the two joining members. The joined body also includes an annular groove portion formed on an inner circumferential surface of the hollow portion at a position separated from a joining face in an axial direction.

A welded structure makes a relationship between one intermittent weld which fixes a long member to a base material and the other intermittent weld which fixes a plate-shaped member to the long member appropriately respond to a type of a load which dominantly acts on the long member. A lower long side edge of a beam member which serves as the long member is fixed onto a machine body frame which serves as the base material by intermittent welds. A top plate which serves as the plate-shaped member is fixed onto an upper long side edge of the beam member by the other intermittent welds. In a region where a load which twists the top plate dominantly acts on the beam member, a parallel weld portion in which the intermittent welds and the intermittent welds are welded in a parallel weld form is employed, and in a region where a bending load from the top plate dominantly acts on the beam member, the zigzag weld portion in which the intermittent weld and the intermittent weld are welded in a zigzag weld form is employed.

An assembly of a first and second constructional part is provided, wherein the first constructional part has a first end and an opposite second end connected by a central part extending substantially perpendicularly to a surface of the second constructional part. The first end of the first constructional part is connected to said surface of the second constructional part with an encapsulating material at least partly surrounding said first end and adhering to said surface of the second constructional part. The first constructional part between its first and second ends is provided with at least one protruding part. The first constructional part in contact the encapsulating material is provided with a flange of which the vertical projection on said surface of the second constructive part completely covers the vertical projection of the protruding part on said surface. A method for making the assembly is provided.

A scaffolding pipe of a structural scaffolding system extends from a first axial pipe end to an opposing second axial pipe end. A receiving portion is provided on the first axial pipe end and an insertion portion is provided on the second axial pipe end. The insertion portion has a reduced cross-section compared with the receiving portion and terminates with a radial shoulder which forms a support face. The receiving portion inner diameter is greater than the insertion portion outer diameter. The receiving portion at the first axial pipe end has one positioning groove which is interrupted or continuous in a peripheral direction which reduces the inner diameter of the receiving portion and which defines the minimum inner diameter of the receiving portion. A pipe wall of the scaffolding pipe has at the first axial pipe end a maximum wall thickness greater than the otherwise smaller wall thickness.

A fixing element has a base area that is provided for the purpose of being welded to a component, and a functional head protruding from a base area that is formed by at least one spherical, or sphere-like element. The fixing element may be welded to a first component and function as a male fixing element that cooperates with a female fixing element of a second component such that the first and second components are detachably connectable via the fixing elements.

A second joining flange formed along an edge of a second panel and a third joining flange formed along an edge of a third panel are superimposed on a first joining flange formed along an edge of a first panel, a seam weld is made in a section in which the first joining flange and the second joining flange form two layers and a section in which the first joining flange and the third joining flange form two layers, and a spot weld is made in a section in which the first joining flange, the second joining flange and the third joining flange form three layers. Such structure enhances production efficiency by increasing welding speed, and facilitates spot welding in the section having three layers, for which seam welding is difficult due to the large number of superimposed sheets, thereby enhancing strength against peel-off.

The ends of two pipeline units are joined together at a pipe joint. Each pipeline unit has a pipe member and a pipe coating surrounding the pipe member. The pipe coating extends along a length of the pipe member. A joint coating surrounds the pipe joint and is made from a material comprising a silicone.

A component connection includes a first component which has a through-hole, from the hole rim of which at least one clamping element projects towards a first side of the first component, and a second component which has a through-hole, from the hole rim of which at least one clamping element projects towards a first side of the second component. The two components bear against one another with their sides remote from the first sides. A connecting element has at least two spherical or spheroidal elements and extends through the two through-holes such that the at least one clamping element of the first component bears against a first of the at least two spherical or spheroidal elements and the at least one clamping element of the second component bears in a clamping manner against a second of the at least two spherical or spheroidal elements.