| 摘要 |
<p>An improved pipe belling process is shown which features a mandrel (43) having spring loaded detents (61) at one circumferential position (63) on an outer working surface (51). A gasket (57) is installed on the outer working surface (51) in abutment with the exposed detents (61). The heated socket end of a thermoplastic pipe is forced over the mandrel exterior (51) and over the gasket (57) with the detents (61) in an extended position. This action causes the heated socket end of the pipe to flow over the gasket (57) and form a retention groove for retaining the gasket (57) before again contacting the working surface (51) of the mandrel (43). The retraction step serves to force the spring loaded detents (61) to the retracted position to allow travel of the thermoplastic pipe over the working surface (51) of the mandrel (43) with the gasket (57) being retained within the formed groove.</p> |
