The invention relates to a method of making a steel Yankee cylinder 1 by welding a cylindrical shell 2 to two end walls 3, 4 such that the cylindrical shell 2 and the end walls 3,4 together form the Yankee cylinder 1. The welding operation is carried out exclusively from the outside of the Yankee cylinder 1 and in the welding operation is carried out as a butt welding operation in which a backing material 7 is used on the inside of the Yankee cylinder 1 such that, between each end wall 3, 4 and the cylindrical shell 1, a single weld bead 8 is formed which extends all the way between the opposing surfaces 5, 6 and completely fuses the opposing surfaces 5, 6 of each end wall 3, 4 and the cylindrical shell 2 respectively.

A backing plate for includes a synthetic diamond portion configured to abut a joint region during a welding operation. A welding clamp includes a plurality of clamping blocks, each including a synthetic diamond portion configured to abut a pipe joint region during a welding operation. Because the backing plate and clamping block each include a synthetic diamond portion, the backing plate and clamping block can withstand high welding temperatures without damaging or diminishing the quality of the weld.

A method for limiting fitting distortion when welding a fitting to an in-service pipeline—where the fitting includes a thick, longitudinally extending, seam located between fitting halves—involves welding, on each side of the fitting, a middle third section of the seam in a pyramid-like fashion using an inward progression starting from an end of the middle third section along a profile of a seam bevel, and welding outer third sections of the seam using an outward progression from an end adjacent to the middle third section along a profile of the seam bevel. The welding of each of the three sections per side includes a temper bead welding technique of at least two layers to provide stress relief in lieu of traditional post weld heat treatment.

A heat-resistant weld backing tape for placement between a backing member and a workpiece to be welded at a root gap. The weld backing tape includes a flexible tape substrate. The tape substrate has a longitudinal length that extends between first and second tape substrate ends, and a lateral width that extends between first and second tape substrate side edges. The tape substrate has a substantially planar first face and a substantially planar second face. The first and second tape substrate faces are mutually parallel and spaced from each other by a tape substrate thickness. The tape substrate length and the tape substrate width are substantially larger than the tape substrate thickness. A heat-resistant material is disposed on the first tape substrate face and arranged to face the workpiece during welding. An adhesive material is disposed on the second tape substrate face and arranged to face the backing member during welding.

A backing plate for includes a synthetic diamond portion configured to abut a joint region during a welding operation. A welding clamp includes a plurality of clamping blocks, each including a synthetic diamond portion configured to abut a pipe joint region during a welding operation. Because the backing plate and clamping block each include a synthetic diamond portion, the backing plate and clamping block can withstand high welding temperatures without damaging or diminishing the quality of the weld.

A one-side submerged arc welding method includes setting: a welding speed transition section, in which welding is performed such that a welding speed is lowered from a welding speed of main welding to a welding speed being 80% or less of the welding speed of main welding; and a low welding speed section, in which welding is performed at a welding speed being 80% or less of the welding speed of main welding. A length of the welding speed transition section is set to be more than 200 mm and 1,000 mm or less. The low welding speed section is set as a section from a position of 100 mm or more and less than 1,000 mm in front of the end part of the steel plates to the end part.

A one-side submerged arc welding method, includes joining two steel plates butted against each other by submerged arc welding from one side using a plurality of electrodes. During the submerged arc welding, at least one of electrode distances between adjacent electrodes in an end part region of the steel plates is reduced to be smaller than the at least one of electrode distances in a region in front of the end part region. Variation in heat input into the electrode moved so as to reduce the at least one of electrode distances in a transitional region in which the at least one of electrode distances is reduced is within 20% relative to the heat input at a starting point of the transitional region.

A method for welding two or more conduits includes aligning end portions thereof in an abutting relationship to define a gap. The method includes performing a spatter free root weld along the gap to configure a root layer while the inner circumferential surface side is unobstructed. After the root weld is complete, an outward thrust is applied along the inner circumferential surfaces of the conduits. During the application of the outward thrust, a filler weld is performed along the gap to fill the gap and to facilitate shrinkage of the filler and root weld materials longitudinally and radially outward while preventing pressing out of the filler and root weld materials radially inward of the inner circumferential surface.

A method for welding two or more conduits includes aligning end portions thereof in an abutting relationship to define a gap. The method includes performing a spatter free root weld along the gap to configure a root layer while the inner circumferential surface side is unobstructed. After the root weld is complete, an outward thrust is applied along the inner circumferential surfaces of the conduits. During the application of the outward thrust, a filler weld is performed along the gap to fill the gap and to facilitate shrinkage of the filler and root weld materials longitudinally and radially outward while preventing pressing out of the filler and root weld materials radially inward of the inner circumferential surface.

A backing plate for includes a synthetic diamond portion configured to abut a joint region during a welding operation. A welding clamp includes a plurality of clamping blocks, each including a synthetic diamond portion configured to abut a pipe joint region during a welding operation. Because the backing plate and clamping block each include a synthetic diamond portion, the backing plate and clamping block can withstand high welding temperatures without damaging or diminishing the quality of the weld.