| 摘要 |
<p>The pipe-bending mandrel may be used by plumbers etc. and fits inside a metal pipe to permit its formation in situ into bends of up to 90 deg. The mandrel comprises a series of co-axial identical interconnected washers (1) of a dia. equal to or nominally less than that of the pipe. A split spring steel ring (5) may be provided between each washer, and a lever-(15) operated tendon (3) may be used to draw the washers together and wedge the rings against the bore of the pipe. The washers re-arrange themselves during bending to adapt to the curvature of the pipe and unlock in succession as traction is relaxed in prepn. for withdrawal. The washers may have a radial flange on each circumferential edge. The outer flange (4) locates a ring (5) to wedge it against the bore of the pipe and the inner flange locates connecting wires (6).</p> |
