Abstract: A welding jig for ensuring concentricity of an interior surface of a pipe with a circular outer periphery of a bolting flange thereon, comprising (i) a frame member; (ii) two spaced-apart rollers positioned at one end of said frame member, each adapted to remain in contacting engagement during welding with said circular outer periphery of said bolting flange; and (iii) a chill block, having a convexly-curved outer surface of a curvature corresponding to a desired inner diameter of said pipe, adapted to be positioned proximate said interior surface of said pipe. The rollers permit translational movement of the chill block about a center point of said pipe flange when the welding jig is placed on the pipe flange, to permit uniform diametrical deposition of weld material on said inner diameter of said pipe flange. A method of making a pipe is further disclosed and claimed.

Abstract: A welding jig for ensuring concentricity of an interior surface of a pipe with a circular outer periphery of a bolting flange thereon, comprising (i) a frame member; (ii) two spaced-apart rollers positioned at one end of said frame member, each adapted to remain in contacting engagement during welding with said circular outer periphery of said bolting flange; and (iii) a chill block, having a convexly-curved outer surface of a curvature corresponding to a desired inner diameter of said pipe, adapted to be positioned proximate said interior surface of said pipe. The rollers permit translational movement of the chill block about a center point of said pipe flange when the welding jig is placed on the pipe flange, to permit uniform diametrical deposition of weld material on said inner diameter of said pipe flange. A method of making a pipe is further disclosed and claimed.

Abstract: A welding jig for ensuring concentricity of an interior surface of a pipe with a circular outer periphery of a bolting flange thereon, comprising (i) a frame member; (ii) two spaced-apart rollers positioned at one end of said frame member, each adapted to remain in contacting engagement during welding with said circular outer periphery of said bolting flange; and (iii) a chill block, having a convexly-curved outer surface of a curvature corresponding to a desired inner diameter of said pipe, adapted to be positioned proximate said interior surface of said pipe. The rollers permit translational movement of the chill block about a center point of said pipe flange when the welding jig is placed on the pipe flange, to permit uniform diametrical deposition of weld material on said inner diameter of said pipe flange. A method of making a pipe is further disclosed and claimed.

Abstract: A welding jig for ensuring concentricity of an interior surface of a pipe with a circular outer periphery of a bolting flange thereon, comprising (i) a frame member; (ii) two spaced-apart rollers positioned at one end of said frame member, each adapted to remain in contacting engagement during welding with said circular outer periphery of said bolting flange; and (iii) a chill block, having a convexly-curved outer surface of a curvature corresponding to a desired inner diameter of said pipe, adapted to be positioned proximate said interior surface of said pipe. The rollers permit translational movement of the chill block about a center point of said pipe flange when the welding jig is placed on the pipe flange, to permit uniform diametrical deposition of weld material on said inner diameter of said pipe flange. A method of making a pipe is further disclosed and claimed.