FIELD: manufacture of pipe-lines and tubings from thermoplastic material. SUBSTANCE: process includes putting of pipe on mandrel at temperature of orientation of thermoplastic material. Mandrel has expanded part that creates expansion towards circumference of pipe. Drawing effort is applied to pipe. Then pipe oriented biaxially is cooled and its outer dimensions are calibrated. Pipe is drawn through calibration hole at some distance from mandrel. Calibration hole is limited by calibration aid. Calibration hole reduces outer dimensions of pipe. EFFECT: manufacture of biaxially oriented pipes with precise outer dimensions. 4 cl, 1 dwg
