Abstract: Hoop expanded PVC pipe and biaxial self-reinforcement PVC pipe were produced with a continuous expansion equipment with cloth bag. When the diameter of the pipe was expanded from Ф40 mm to Ф50 mm ，the hoop tensile strength increased 23 % ～25 %, the hoop young's modulus increased 12 %. Through biaxial self-reinforcement, the hoop tensile strength of the pipe increased 26 % ～33 %, hoop young's modulus increased 30 %～33 %. For the biaxial self-reinforcement pipe, the hoop tensile strength increased with increasing axial stretching ratio.

Key words: biaxial orientation, pipe, biaxial self-reinforcement, poly(vinyl chloride), mechanical property, axial stretching ratio