| 摘要 |
1,127,756. Helically-wound pipes. M. HAWERKAMP. 21 Dec., 1965 [30 Dec., 1964], No. 54242/63. Heading F2P. [Also in Division B8] A process for making a tubular member which may be utilized as a tube or a container comprises helically wrapping a thermo-plastic strip 1 in a plastic condition, for example when taken directly from an extruder or preheater, together with a profiling section 6 about a plain mandrel 3, welding together edges of adjacent strip turns using a press roller 4 having a matching recessed profile to force the strip into conformity with-the profile section, and removing the profiling section from the recess it has formedin the wound strip. As shown, the profiling section is semi-circular in cross-section. In a modification, Fig. 3 (not shown), the tubular member is formed with end flanges by using annular members 6A inaddition to the helically wound profiling section-. Althorgh the adjacent turns of the strip are shown as having oblique butt joints 2, they may also be joined-in overlapping relationship. |
