Improved PVC-O pipe production method

The invention provides an improved PVC-O pipe production method. The improved PVC-O pipe production method comprises the steps of raw material blending, extrusion traction, vacuum heating, two-way stretching of a PVC pipe through a stretching device at a set temperature, cooling and shaping of a stretched PVC-O pipe, and simultaneous cutting and flaring operation. According to the method, a pipe blank is gradually and uniformly stretched and shaped in the radial direction, and a fan is matched in the rotating and expanding process through a spiral blade, so that a good ventilation condition and a uniform temperature environment are always kept in an outer barrel, a good radial stretching effect is achieved, and the radial strength of the PVC-O pipe is further enhanced. 本发明提供一种改进的PVC-O管材的生产方法，包括原料调配、挤出牵引、真空加热、在设定温度下通过拉伸装置对PVC管材进行双向拉伸、对拉伸后的PVC-O管材进行冷却定型，之后一次进行切割、扩口的操作。本发明将管坯的径向逐渐均匀拉伸并定型，且在螺旋叶片转动撑胀过程中配合风机，使得外筒内始终保持良好的通风条件和均匀的温度环境，达到良好的径向拉伸效果，从而进一步增强PVC-O管材的径向强度。