Abstract: A pipe, the inner surface of which is lined with a thermoplastic layer, is produced by a process comprising the following steps: a) a metal pipe is provided, b) a tubular inliner composed of a thermoplastic material is provided, c) a tape is cohesively helically bonded to the inliner, wherein the region of the contact surface of the tape consists of a moulding composition or an adhesive which adhere firmly to the surface of the inliner, and wherein the region of the opposing surface of the tape consists of a moulding composition or an adhesive which adhere firmly to the metal of the pipe, wherein the tape contains unidirectional reinforcing fibers; d) the cross section of the inliner is optionally reduced by exposure to an external force, e) the inliner is inserted into the metal pipe, f) by means of contact pressure and optionally heat, the inliner and metal pipe are firmly bonded to each other.

Abstract: A pipe, the inner surface of which is lined with a thermoplastic layer, is produced by a process comprising the following steps: a) a metal pipe is provided, b) a tubular inliner composed of a thermoplastic material is provided, c) a tape is cohesively helically bonded to the inliner, wherein the region of the contact surface of the tape consists of a moulding composition or an adhesive which adhere firmly to the surface of the inliner, and wherein the region of the opposing surface of the tape consists of a moulding composition or an adhesive which adhere firmly to the metal of the pipe, wherein the tape contains unidirectional reinforcing fibers; d) the cross section of the inliner is optionally reduced by exposure to an external force, e) the inliner is inserted into the metal pipe, f) by means of contact pressure and optionally heat, the inliner and metal pipe are firmly bonded to each other.

Abstract: The invention relates to a positioning device (203) for a manual welding machine (300), particularly for a plastic welding machine, comprising at least one contact shield (16) associated with the manual welding machine (300) and a positioning ring (3) associated with the material to be welded. In order to perform precise welding and to prevent the subsequent slipping of the manual welding machine (300), according to the invention, the positioning ring (3) can be fixed to the material to be welded and a contact shield (16) that can be inserted in the positioning ring (3) transfers a pressure distributed evenly over the circumference to the materials to be welded, in order to allow secure welding over a large area.

Abstract: An arrangement is provided for securing a lining material of a wall inner surface of a load-bearing construction, such as a container, apparatus, duct, housing, or column, which is acted upon by a gaseous or liquid medium. Multiple securing points are provided, and are arranged in a distributed manner and connected to the wall inner surface in order to secure the lining material. In order to reliably secure a lining material to a wall inner surface subject to great tractive forces, the fastening elements have at least one holding element which connects the wall inner surfaces to the lining material, and which can be fixed by a pressure element in a force- and/or form-fit manner.

Abstract: An arrangement is provided for securing a lining material of a wall inner surface of a load-bearing construction, such as a container, apparatus, duct, housing, or column, which is acted upon by a gaseous or liquid medium. Multiple securing points are provided, and are arranged in a distributed manner and connected to the wall inner surface in order to secure the lining material. In order to reliably secure a lining material to a wall inner surface subject to great tractive forces, the fastening elements have at least one holding element which connects the wall inner surfaces to the lining material, and which can be fixed by a pressure element in a force- and/or form-fit manner.

Abstract: The invention relates to a positioning device (203) for a manual welding machine (300), particularly for a plastic welding machine, comprising at least one contact shield (16) associated with the manual welding machine (300) and a positioning ring (3) associated with the material to be welded. In order to perform precise welding and to prevent the subsequent slipping of the manual welding machine (300), according to the invention, the positioning ring (3) can be fixed to the material to be welded and a contact shield (16) that can be inserted in the positioning ring (3) transfers a pressure distributed evenly over the circumference to the materials to be welded, in order to allow secure welding over a large area.

Abstract: Polyethylene compositions, which can be processed by injection molding, comprising 40% to 99% of a polyethylene having a limiting viscosity number of 1000 to 5000 ml/g and 60% to 1% of a polyethylene having a limiting viscosity number of 100 to 700 ml/g. The molecular weight distribution of each of the polyethylene components is less than 9. The limiting viscosity number of the compositions is at least 1500 ml/g. Shaped articles produced from these compositions have excellent wear resistance, high notched impact strength, and do not delaminate.

Abstract: Polyethylene compositions for producing moldings have a surface resistance of at most 10.sup.9 .OMEGA. includinga) 0.1% to 80% of a polyethylene or an ethylene copolymer having an intrinsic viscosity of from 100 to 700 ml/g;b) 99.9% to 20% of a polyethylene having an intrinsic viscosity of at least 1600 ml/g;c) 1.0% to 10.0, based on the polymer mixture of a and b, of carbon black; andwherein the sum of Components a and b is 100% and the intrinsic viscosity of the polymer mixture of a and b is at least 1600 ml/g.

Abstract: Porous moldings of ultrahigh-molecular-weight polyethylene obtained by injection molding polyethylenes having an intrinsic viscosity of 500 to 5000 ml/g, a mean particle size of 100 to 1500 .mu.m, and a bulk density of at least 0.35 g/cm.sup.3. The polymer is preferably molded in an injection-molding machine at 160.degree. to 260.degree. C. and an injection pressure of 80 to 150 MPa. The ratio between the flow distance of the material in the injection mold and the wall thickness of the molding is a maximum of 7.5.