Patent ID: 7810696

Claim:
An apparatus for clamping adjacent ends of a first pipe section and a second pipe section, said apparatus comprising: a) a frame; b) a plurality of clamping members for engaging said adjacent ends of said first pipe section and second pipe section extensibly mounted to said frame, said clamping members being movable between a retracted position and an extended clamping position; 1) wherein each of said plurality of clamping members comprises a clamping shoe and a connecting member that connects said clamping shoe to said frame; 2) wherein each of said clamping shoes comprises a clamping surface which contacts the internal surface of said first pipe section and said second pipe section when said clamping members are in the extended clamping position; 3) wherein each of said clamping shoes comprises a longitudinal groove on said clamping surface, said longitudinal groove being oriented parallel to said adjacent ends of said first pipe section and said second pipe section, thereby dividing said clamping shoe into a first pipe contact surface and a second pipe contact surface; 4) wherein each of said clamping shoes further comprises at least one gas passageway through said clamping shoe, said gas passageway extending from a point on a surface of said clamping shoe away from said clamping surface to a termination point within said longitudinal groove on said clamping surface; and 5) wherein each of said clamping shoes further comprises one or more alignment guide devices protruding from one or more of said clamping surfaces along said longitudinal grooves; c) a means for delivering a purge gas to said groove through said gas passageway; and d) a means for moving said clamping members between said retracted position and said extended clamping position.