| 摘要 |
PIPE STRETCHING APPARATUS An apparatus for stretching pipe having first and second elongated mandrels each having a longitudinal axis and an outer surface of a predetermined cross-section transverse to the longitudinal axis of each mandrel. A displacement means is included for adjusting the relative distance between the mandrels. A cylindrical spiral ribbed pipe is positioned lengthwise over the mandrels with the mandrels fitting against the inner wall of the pipe, The displacement means increases the relative distance between the mandrels so as to reform the original circular end cross-sectional shape of the pipe. |
