Abstract: Corrugations are removed from the end of a helically corrugated pipe by compressing the end of the pipe between a plurality of radially movable die segments. By choosing appropriately-shaped die segments and die-actuating cams, the end of the pipe can be expanded, or shrunk to a diameter less than that of an imaginary cylinder defined by a surface of revolution contacting the innermost surfaces of the pipe. Products manufactured in accordance with the method of the invention have an end portion with an accurately controlled diameter; a minimum of pipe length is taken up by the modification.

Abstract: Corrugations are removed from the end of a helically corrugated pipe by compressing the end of the pipe between a plurality of radially movable die segments. By choosing appropriately-shaped die segments and die-actuating cams, the end of the pipe can be expanded, or shrunk to a diameter less than that of an imaginary cylinder defined by a surface of revolution contacting the innermost surfaces of the pipe. Products manufactured in accordance with the method of the invention have an end portion with an accurately controlled diameter; a minimum of pipe length is taken up by the modification.

Abstract: A composite pile includes a wooden section and a helically corrugated shell secured to the wooden section by a transition fitting. The transition fitting is fitted telescopically to a tubular end portion of the shell by a circumferential weld which is embedded in the wooden section. Because the weld is very strong and is disposed within the wooden section, the strength of transition-to-shell connection is increased over prior composite piles. The pile manufacture includes the step of removing corrugations from the end of a shell by squeezing the end of the shell between radially movable, annular die segments.