Methods and apparatus for making fiber reinforced plastic pipe

Claim 1

A device for sealing the end of a pipe comprising a bearing plate having a central, internally threaded opening, a solid threaded shaft extending through said opening to clamp and unclamp the device from a pipe, manually operable means for rotating the shaft, the forward end of the shaft having a disk fixed thereto of a larger diameter than the diameter of the shaft, an O-ring positioned adjacent the rear side of the disk, a hollow plug having a central bore, said O-ring being cooperable with the wall of said bore, said plug having a counterbore to receive said disk, the intersection of the bore and counterbore providing a shoulder cooperable with said disk in the clamped position of the device, whereby the O-ring is in sealing engagement with the bore's wall, the outer side of said plug being convergingly tapered toward said bearing plate to provide a ramp, a plurality of segments providing a split, expandable sleeve overlying said plug, said segments being matingly tapered on their inner sides for cooperation with said ramp, the segments being provided on their outer sides with means for gripping the interior of a pipe, an elastic retaining ring to resiliently maintain said segments against the underlying plug, and means connecting the segments to said bearing plate in a manner permitting the segments to move in a radial direction.

Claim 2

A device for sealing the end of a pipe comprising a bearing plate having a central, internally threaded opening, a solid threaded shaft extending through said opening to clamp and unclamp the device from a pipe, manually operable means for rotating the shaft, the forward end of the shaft having a disk fixed thereto of a larger diameter than the diameter of the shaft, an O-ring positioned adjacent the rear side of the disk, a hollow plug having a central bore, said O-ring being cooperable with the wall of said bore, said plug having a counterbore to receive said disk, the intersection of the bore and counterbore providing a shoulder cooperable with said disk in the clamped position of the device, whereby the O-ring is in sealing engagement with the bore's wall, the outer side of said plug being convergingly tapered toward said bearing plate to provide a ramp, a plurality of segments providing a split, expandable sleeve overlying said plug, said segments being matingly tapered on their inner sides for cooperation with said ramp, the segments being provided on their outer sides with means for gripping the interior of a pipe, an elastic retaining ring to resiliently maintain said segments against the underlying plug, and means connecting the segments to said bearing plate in a manner permitting the segments to move in a radial direction.