Abstract: Pipes of a weldable polymer material are welded with a muff of a weldable polymer material. The method includes placing the muff with an overlap over the ends of the pipes, welding the muff to the ends of the pipes through placement of an electrically conducting band that is permeable to molten plastic between the pipe and the muff, connecting a power supply to the band through feed cables, and supplying an electrical current in order to heat the band and the surrounding polymer material such that they melt together around the band in order to form a weld. The temperature of the weld is calculated through adding the initial ambient temperature of the weld and the increase in temperature of the band.

Abstract: A method for joining or repairing a pipe system that comprises a least two pipes made of weldable plastic material, comprising: fitting a sleeve made of weldable plastic material the distance between the two pipes, the sleeve having a length A that exceeds the distance B between the mutually opposing pipes, such as to overlap each pipe end to a given extent C; placing an electrically conductive band around one of the pipes, the band having two ends; connecting the band ends to each other by placing the band ends overlapping each other; fitting the sleeve over and against the pipe and the band, and applying an electric current to the band over a given period of time, thereby heating the band to a determined temperature for a determined time and fusing the band with the plastic surfaces of the pipe and the sleeve lying in abutment therewith to form a welding joint being fully executed around the pipe and inside the sleeve.

Abstract: A method for installation and repair of insulated piping includes placing a sleeve coupling, made of a weldable polymer material incorporating a slit that runs lengthwise along the piping, and whose length exceeds the distance between the outer pipes' ends, over the exposed section of the inner pipe so as to overlap the ends of the outer pipes, and welding the sleeve coupling to the outer pipe at the ends of the outer pipes, by placing an electrically conductive band between the outer pipe and the sleeve coupling, ensuring that free ends of the band project upward through the slit. A power converter which has a quasi-resonant converter is employed to produce the electric current that is to be connected to the band.

Abstract: Pipes of a weldable polymer material are welded with a muff of a weldable polymer material. The method includes placing the muff with an overlap over the ends of the pipes, welding the muff to the ends of the pipes through placement of an electrically conducting band that is permeable to molten plastic between the pipe and the muff, connecting a power supply to the band through feed cables, and supplying an electrical current in order to heat the band and the surrounding polymer material such that they melt together around the band in order to form a weld. The temperature of the weld is calculated through adding the initial ambient temperature of the weld and the increase in temperature of the band.

Abstract: The present invention relates to a method for the installation and repair of insulated piping, wherein the insulated piping comprises an outer pipe 1, 1.1 or 1.2 made of a weldable polymer material that encases an inner pipe 2, 2.1 or 2.2 embedded in an insulating layer 4, and wherein the inner pipe 2, 2.1 and 2.2 has been substantially exposed over a section A between the ends 1 a and 1 b of the two outer pipes. The method comprises placing of a sleeve coupling 7, made of a weldable polymer material incorporating a slit 8 that runs lengthwise along the piping, and whose length 5 exceeds the distance A between the outer pipes' ends 1 a and 1 b, over the exposed section A of the inner pipe 2, or 2.1 and 2.2, and with overlapping of the outer pipes' ends 1 a and 1 b; welding the sleeve coupling 7 to the outer pipes 1, or 1.1 and 1.2, the outer pipes' ends 1 a and 1 b, by placing an electrically conductive band 9 that is pervious to molten plastic between the outer pipe 1, or 1.1 and 1.