SU1266692A1 - Method of welding annular joints - Google Patents

Abstract

A METHOD FOR WELDING RING BITS, in which weld joints are assembled on a backing ring provided with a forming groove, and are welded with a simultaneous running-in butt with a roller located in front of the welding torch and moving with a welding speed that is different in that when welding parts of different rigidity, the joint run-in is made with a roller, on the cylindrical working surface of which two annular grooves are made and a conical ledge located between it The smaller diameter of the protrusion is equal to the diameter of the cylindrical part of the roller, the larger diameter exceeds the diameter of the cylindrical part by not less than 0.2 of the wall thickness of the part of lesser rigidity, and the width of the protrusion is less than 0.5 of the width of the forming groove; a meter of a conical protrusion is placed (L C over the butt line, the second groove above the edge of the forming groove from the part of lesser rigidity, and the roller itself is less than 100 wall thicknesses from the welding torch th details.

Description

The invention relates to welding, in particular to methods of arc welding of annular joints of parts, and can be used in various fields of engineering.

The purpose of the invention is to improve the quality of the joint when welding parts of different rigidity.

FIG. 1 shows a scheme for carrying out the method; in FIG. 2, section A-A in FIG. one.

The method is carried out as follows.

Before welding, parts 1 and 2 are assembled on a manipulator or roller stand. The parts to be welded 1 and 2, having different rigidity, are assembled with the help of a backing ring 3, which is arranged symmetrically relative to the joint 4. A forming groove 4 is made on the backing ring 3 and when assembling the joint 5, edges 6 and 7 are arranged along its axis. The width of the groove is 2-6, and the depth of the 1-5 throng of the wall of the less rigid jets 2.

A roller 8 is installed above the joint, on the cylindrical working surface of which two grooves 9 and 10 are made and a conical protrusion 11 located between them. The diameter of the smaller base of the protrusion 11 is equal to the diameter of the cylindrical surfaces 12 and 13 of the roller 8. The diameter of the larger bases of the protrusion 11 is larger than the diameter of the cylindrical surfaces 12 and 13 by at least 0, 2 wall thickness of the less rigid part 2. The width of the protrusion 11 is less than half the width of the forming groove 4.

The roller 8 is mounted on the welding device so that the distance from the point of contact with the edges 6 and 7 to the welding torch 14 is more than 100 wall thicknesses of the less rigid part 2, while the groove 9 from the larger diameter of the protrusion 11 is positioned above the line the joint, and the second groove 10 above the edge 15 of the forming groove 4 from the side of the less rigid part 2.

After preparing the parts for welding, they put on the retaining rings 16 and 17, using the handle 18, lower the roller 8 until the contact of its cylindrical surfaces 12 and 13 with parts 1 and 2, while the conical protrusion 11 bends the edge less

rigid part 2 inside the groove, include the rotation of parts 1 and 2 and start welding.

Geometrical parameters of the groove 4

and the protrusion 11 is determined experimentally on the condition of ensuring the formation of a reverse roller and of excluding the welding of the washer 3 to the product, as well as on the condition of ensuring the hem of the less rigid part. With smaller values of the width and depth of the groove, as well as when exceeding the larger diameter of the conical protrusion 11 relative to the diameter

cylindrical surfaces 12 and 13 are less than 0.2 times the wall thickness of a less rigid pipe, due to the presence of residual stresses in the edge 7, it returns to its original state and does not bend. For large values of the geometrical parameters of the groove 4, excessive bending of the edge 7 inwards is possible, which leads to a reverse bias of the edges of the parts being welded.

The distance between the welding torch 14 and the roller 8 is also determined experimentally. Increasing this distance to more than 100

the wall thickness of the less rigid part 2 may prematurely return the edge 7 to its original position under the action of the welding arc. In the process of welding under the action

heating on aluminum parts

alloys deformation (swelling) of the edges being welded, however, due to the simultaneous pressing of the more rigid edge 6 and bending

less hard edge 7 roller 8

total residual strain becomes minimal. After the roller 8 has reached the start point of welding, it is lifted using the handle 18,

and continue welding until closure

ring seam with overlapping of the beginning of welding.

The application of the proposed method allows to improve the quality of welded

joints, to ensure its required geometrical parameters and to exclude the deformation of edges, their relative displacement caused by thermal, fasciation during welding. The combination of hemming and welding operations improves productivity and also reduces the costs associated with edge preparation.

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Claims (1)

METHOD FOR WELDING RING JOINTS, in which the welded joints are assembled on a washer equipped with a forming groove, and welding is performed with simultaneous rolling of the joint with a roller located in front of the welding torch and moving with a welding speed, characterized in that, in order to improve the quality of the connection when welding parts of different stiffness, the joint is run-in by a roller, on the cylindrical working surface of which two annular grooves and a conical protrusion located between them are made, while The larger diameter of the protrusion is equal to the diameter of the cylindrical part of the roller, the larger diameter exceeds the diameter of the cylindrical part by at least 0.2 of the wall thickness of the part of less rigidity, and the width of the protrusion is less than 0.5 of the width of the forming groove, when running the first groove from the side of a larger diameter a conical protrusion is placed above the junction line, a second groove above the edge of the forming groove from the side of the part of lower stiffness, and the roller itself is placed from the welding torch at a distance of not more than 100 wall thicknesses of a less rigid part. FIG;