To provide a clamping mechanism, and an apparatus and a method for manufacturing joined object, all of which allow, with a simple configuration, clamping of clamp objects having sizes different from each other, stably at their positions. A clamping mechanism 10 includes a plurality of clamp claws 11 configured to clamp an object S to be clamped; a plurality of support shafts 16 configured to pivotally support a corresponding clamp claw 11, wherein the corresponding clamp claw 11 pivots around the support shaft 16 for opening or closing movement; and a mover apparatus 12 configured to cause the clamp claw 11 to perform the opening or closing movement. A joined object manufacturing apparatus includes the clamping mechanism 10, a holder configured to hold an object to be joined, and a joining apparatus configured to join the object S clamped by the clamping mechanism 10 and the object to be joined that is held by the holder. A method for manufacturing a joined object includes causing the clamping mechanism 10 to clamp the object S by use of the joined object manufacturing apparatus, causing the holder to hold the object to be joined, and joining the both.

An apparatus for aligning sections of pipe includes a first clamp member and a second clamp member coupled with the first clamp member. The first and second clamp members each include a first clamp jaw and a second clamp jaw longitudinally spaced from the first clamp jaw. Each one of a first plurality of turnbuckle assemblies is coupled with each one of the first and second clamp jaws of the first clamp member, and each one of a second plurality of turnbuckle assemblies is coupled with each one of the first and second clamp jaws of the second clamp member. An assembly made from a kit of components is also disclosed. The kit includes an apparatus for aligning sections of pipe, and a plurality of shoe inserts. The assembly includes the apparatus and at least two of the shoe inserts coupled with the apparatus.

An alignment tool for positioning and aligning the adjacent ends of pipes in optimum desired relation for joining the tubular sections by welding. The alignment tool comprises a first and second annularly shaped clamping rings and a plurality of swivel assemblies connecting and circumferentially spaced about the first and second clamping rings, wherein the swivel assemblies adjust the distance between the first and second clamping rings and adjust the first and second clamping rings transversely and axially with respect to each other. Each swivel assembly comprises a first swivel portion connected to the first clamping ring, a second swivel portion connected to the second clamping ring, and a threaded bolt extending through the first swivel portion and the second swivel portion. The first swivel portion comprises an axel alignment swivel including a longitudinal shaft with a first partial spherical portion at its center, wherein the first partial spherical portion is retained within a bore extending through the first clamping ring. The second swivel portion comprises a second partial spherical portion that is retained within a bore extending through the second clamping ring.

A system for carrying out operations along an annular junction portion of a pipeline is provided with: a frame comprising a C-shaped structure, which is configured to be selectively clamped about a pipeline extending along a longitudinal axis and near an annular junction portion, and at least one driving device arranged along an arc of an annular path and coupled to the structure; a support arm configured to rest on the pipeline and connected to the structure for maintaining the laying plane of the driving device substantially orthogonal to the longitudinal axis; a carriage slideably coupled to the driving device; and at least one operating device configured to carry out operations along the annular junction portion and cantilever supported by said annular segment.

A method of controlling a back weld root surface includes arranging a sealing portion along the back weld root surface of a workpiece to form a purge region adjacent to a section of a joint, supplying a shielding gas within the purge region at a first flow rate, and applying a weld deposit across a front surface of the section of the joint. The shielding gas displaces an ambient environment within the purge region, and the back weld root surface of the weld deposit includes a positive root penetration relative to the back weld root surface based at least in part on the shielding gas within the purge region.

A method of controlling a back weld root surface includes arranging a sealing portion along the back weld root surface of a workpiece to form a purge region adjacent to a section of a joint, supplying a shielding gas within the purge region at a first flow rate, and applying a weld deposit across a front surface of the section of the joint. The shielding gas displaces an ambient environment within the purge region, and the back weld root surface of the weld deposit includes a positive root penetration relative to the back weld root surface based at least in part on the shielding gas within the purge region.

The assembly and welding mill for production of pipes includes a tubular billet feed device with a roller table having a longitudinal axis and passing through the assembly and welding stand with radial hold-down roller beams intended for reduction of a tubular billet that travels along the roller table and a longitudinally oriented guide knife, a carriage with rollers enabling rotation of the rollers on the inner surface of the tubular billet being moved through the assembly and welding stand. On the supporting elements of assembly and welding stand there is a laser welding head or a laser-arc hybrid welding head that can travel in transverse and vertical directions and around longitudinal axis. The carriage is rigidly connected with the supporting elements of the assembly and welding stand through a vertically oriented and longitudinally directed connecting knife. The guide knife is intended for tubular billet positioning through opening of edges at 12 o'clock position and is mounted on the supporting elements of the assembly and welding stand configured to enable vertical travel and fixation. On the carriage, there is a hold-down roller facing upwards that can travel in vertical direction to act on the edges of tubular billet from the inner side, while one of the roller beams is installed vertically that can act on the tubular billet edges from the outer side. Technical result: application of a root weld with laser technologies with guaranteed alignment of tubular billet edges regardless of size.

The invention relates to a pipeline internal centering device for centering a first pipe (28) relative to a second pipe (30), having a centering unit (12) for aligning the second pipe (30) relative to the first pipe (28), and having a transport device (14) for moving along a longitudinal axis (L) of the pipeline internal centering device (10). According to the invention, a rotary device (48) is provided by means of which the pipeline internal centering device (10) can be rotated about its longitudinal axis (L).

The present disclosure provides a method of all-position plasma welding process for titanium alloy pipeline, which may be used for welding a titanium alloy pipeline made of TA2 or TC4, with a wall thickness of 3˜16 mm, and a pipe diameter of 108 mm or more. When the wall thickness is 3˜9 mm, a keyhole type technology may be used for one-time welding formation, and when the wall thickness is 9˜16 mm, grooving treatment needs to be performed for the pipeline, and the keyhole type technology is used for backing welding, and then filling welding and covering welding are performed using filler wire welding through a melt-in technology. The method includes following steps: S1: performing pre-welding treatment for the pipeline; S2: clamping the pipeline; S3: setting welding parameters; S4: starting the welding.

The present disclosure provides a method of all-position plasma welding process for titanium alloy pipeline, which may be used for welding a titanium alloy pipeline made of TA2 or TC4, with a wall thickness of 3˜16 mm, and a pipe diameter of 108 mm or more. When the wall thickness is 3˜9 mm, a keyhole type technology may be used for one-time welding formation, and when the wall thickness is 9˜16 mm, grooving treatment needs to be performed for the pipeline, and the keyhole type technology is used for backing welding, and then filling welding and covering welding are performed using filler wire welding through a melt-in technology. The method includes following steps: S1: performing pre-welding treatment for the pipeline; S2: clamping the pipeline; S3: setting welding parameters; S4: starting the welding.