Abstract: A pipe tape tensioner (26) is disclosed for applying tape (12) with constant tension to a pipe (14). The pipe tape tensioner (26) employs a primary roller (32) rotatably mounted on a base (34). First clutch disks (92) and second clutch disks (100) are urged against each other by clutch springs (104) to generate a frictional resistance to rotation of the primary roller relative to the base (34) to tension the tape (12) engaged with the outer surface (36) of the primary roller (32). The first clutch disks (92) are splined to the splines (58) formed on the interior of the base (34). The second clutch disks (100) are splined to the hub (96) of the primary roller (32). A cooling fluid can be employed to cool the splines and surrounding components.

Abstract: Apparatus for applying a primer paint coating onto a pipe wherein a structure movable along the pipe forms an enclosed annular cavity about the pipe. Primer paint fills the cavity and wets the complete circumference of the pipe. The cavity is filled by means of gravity flow with the surplus primer being collected in a reservoir and pumped back to the top of the cavity. Means are provided to wipe the primer to a predetermined thickness and returns the surplus to the reservoir. A gas rich environment surrounds the paint filled cavity and wiper means.

Abstract: An internal mandrel (10) is disclosed which is used for supporting the inner wall (30) of a pipe (12) during bending. The internal mandrel includes a urethane plug (31) which is compressed between the piston (60) of a hydraulic cylinder (56) and an end plate (36). This expands the urethane radially outward into contact with the inner wall (30) of the pipe to support the pipe during bending. Resilient steel strips (88) can be mounted on the exterior surface of the urethane plug (31) at the inside bend of the pipe to increase the effective wall thickness of the pipe at the inner bend to reduce the likelihood of deformation during bending. In a second embodiment, internal mandrel (200) includes an annular urethane plug (204) positioned between a resilient cylinder (202) and the inner wall of the pipe (12).

Abstract: An improved tape applying device (12) is provided. A number of tape roll support spindles (34) are pivotally mounted to a wrapping sprocket (14) which rotates about an axis (18). The spindles (34) support tape rolls (22). As the wrapping sprocket (14) rotates, the tape from these tape rolls are wrapped about a pipe (26). A rigid ring (66) is supported on a number of struts (50) spaced from and coaxial with the wrapping sprocket (14). A brace arm assembly (69) is secured between the ring (66) and selected spindles (34) to oppose centrifugal forces generated when the annular member rotates to apply the tape to the pipe.

Abstract: A pipe bending machine (10) is described which incorporates a bending die (14) which supports coated pipe during bending without damaging the coating. In one embodiment, the bending die (14) employs a conventional die (30) with a plurality of longitudinal rods (40, 42, 44) spaced from the inner surface of the die (30) and in pipe confronting relation. When the pipe is urged against the bending die in the machine, the rods precompress the material thereunder for transmitting the bending forces. The rods (40, 42, 44) are spaced a sufficient distance from each other in the transverse direction about the inner surface of the die to permit the material to flow outward therebetween to reduce the stresses in the coating. In a second embodiment, a plurality of transversely extending rings (62, 64 66) are positioned on the inner surface of a conventional die (30) which further act to support bending forces without damage to the coating.