Clyde F Kaunitz

US Patent:

45948739, Jun 17, 1986

Filed:

Oct 29, 1984

Appl. No.:

6/666177

Inventors:

Clyde F. Kaunitz - Bay City MI

International Classification:

B21D 4102
B21D 1900

US Classification:

72340

Abstract:

A method and apparatus is disclosed for preparing the ends of large diameter metal pipe, such as that employed in cross-country pipelines, for welding of two pipe sections in end-to-end relationship with each other. Apparatus is provided for performing the method under which the pipe end to be prepared is first radially expanded uniformly around the entire circumference beyond its elastic limit to a predetermined diameter. While the expanding device holds the pipe end in this expanded position, a lathe aligned and associated with the expanding device is actuated to a machine beveled surface on the pipe end. Upon release and removal of the expansion mechanism, the pipe end remains in a permanently deformed truly circular configuration of a precisely predetermined diameter with the general plane of the pipe end accurately located in true perpendicularly to the pipe axis, thus enabling ends of a pair of adjacent pipe sections to be precisely aligned with each other around the entire pipe circumference in preparation for the welding of the two sections to each other.