POLYMER PIPE LINE Russian patent published in 2002 - IPC

FIELD: manufacture of pipe lines for oil, gas and chemical industries; transportation of aggressive media. SUBSTANCE: pipes made from reinforced thermoplastic are connected by means of permanent joints provided with outer metal sectional sleeve; parts of bush inside this sleeve are welded, thus obtaining thermoplastic lock. Body of permanent joint is made in form of metal sleeve assembled from sections of metal pipes welded together over end surfaces at angle of 0≤α<90^°; walls of said sleeve are provided with cavities in form of holes for escape of flash and circular bores made in inner surfaces of sections of pipes with generating surfaces at angle of β≥0 relative to axes of pipes being connected; metal sleeve embraces cylindrical surfaces of thermoplastic bush with tips for introducing pipes; bush consists of two parts welded together over end surfaces ; tips embrace cylindrical surfaces of pipes; body has thermoplastic lock formed in the course of welding the end faces of bush by filling the cavities made in joint with molten thermoplastic; parts of bush are introduced in thermostatted sleeve and are welded there at the same angle of 0≤α<90^°, as sections of metal pipes. EFFECT: possibility of using pipe line at any turn of route without additional units and inserts; facilitated procedure under field conditions; enhanced reliability during operation with aggressive media at high pressures. 1 dwg