POLYETHYLENE PIPE MAKING METHOD Russian patent published in 2002 - IPC

FIELD: laying of pipelines for transportation of gaseous and liquid chemically aggressive media at variable pressures and temperatures mainly in middle and southern latitudes. SUBSTANCE: method of pipe making includes making of spiral grooves in pipe and fitting-in long-length member in groove with subsequent coating with elastic material. Single-layer polymer pipe is used on which spiral groove is made using a cutter. Depth of groove should not exceed half of pipe wall thickness, and is defined by section of long-length member. Coating of long-length member is done by welding using extruder with preliminary heating of groove walls. EFFECT: provision of reliable operation of pipe at high temperatures, reduced labour input at manufacture. 2 dwg