JPS58192693A - Shape of butt welding groove of pipes - Google Patents

Abstract

PURPOSE:To provide a titled shape of a welding groove which enables the exact and easy mating of beveled ends and tack welding in butt welding of pipes, by forming the beveled end part of one of the pipes to be butt welded to a female shape and forming the beveled end part of the other pipe to a male shape conforming to said female shape. CONSTITUTION:The groove of the case in which, for example, a butting part 3 is inclined with respect to the axial center of a pipe in butt welding of a pipe 1 and a nozzle stub 2 is formed to the following shape: Bevels 4 and 5 are formed by edge preparation respectively on the inside circumferential surface in the joint part of the pipe 1 and the inside circumferential surface in the joint part of the stub 2. The beveled end part 6a on the pipe 1 side is formed to a convergent male shape and the beveled end part 6b on the stub 2 side is formed to a female shape conforming to said male shape. The end part 6a on the pipe 1 side is butted and fitted to the end part 6b on the stub 2 side and the bevels 4, 5 are welded successively from the inside by a welding machine 7 in the stage of welding the pipe 1 to the stub 2. The mating of the beveled ends and tack welding are accomplished easily and exactly by the above-mentioned method even without any special jig.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to improving the shape of a groove formed in a weld joint of a pipe when butt welding the pipe.

The following problems arise in pipe butt welding when the butt part of the pipe is inclined with respect to the pipe axis and there is no space necessary for welding on the outside of the pipe.

(1) Difficult to align grooves.

(11) Slip-off and deformation occur during tack welding.

(ili) The jig for aligning the grooves and the jig for fixing the groove during tack welding cannot be used for a single period unless there is a work space on the outside of the pipe, so they cannot be used, resulting in incomplete welding. .

The present invention has been made with the object of making it possible to accurately and easily perform groove alignment and temporary welding in pipe butt welding under the above conditions.

Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 shows an example in which the present invention is implemented as a groove shape when the butt part (3) is inclined with respect to the pipe axis in butt welding of a pipe (1) and a nozzle (2). Bevel processing is performed on the inner circumferential surface of the joint of the pipe (1) and the inner circumferential surface of the joint of the nozzle stub (2) to form a bevel (4) and a groove (5). (6α) has a tapered female shape, and the open end portion (6b) on the nozzle side has a female shape that matches the female shape. Note that (7) is a welding machine.

When welding the pipe (1) to the nozzle stub (2) in a configuration where no ) to weld grooves (4) and (5) from the inside.

In this way, the joints of the pipe (1) and nozzle (2) can be fitted and fixed by male and female shapes, making groove alignment and tack welding easy and accurate without the need for special jigs. It can be carried out. Also, since the grooves (4) and (5) are provided on the inner peripheral surface of the joint and welded from the inside, the groove angle will not change due to deformation of the joint due to welding, and the groove angle will not change in the lateral direction of the joint. Since the contraction (in the axial direction of the pipe) is uniform, there is no collapse of the pipe axis due to welding, and furthermore, T I G
Good Uranami welding can be obtained by welding.

FIG. 2 shows another embodiment of the present invention, in which a pipe (1
) is made into a female stepped shape, and the nozzle base (2
) has a female stepped shape that fits into the female stepped shape. In other respects, the configuration is the same as that in FIG. 1, and the same reference numerals as in FIG. 1 indicate the same parts.

Further, FIG. 3 shows an example in which the present invention is implemented when the abutment part (3) is made perpendicular to the pipe axis; here, the pipe (
The open end (9a) of 1) is made into a female stepped shape, and the nozzle holder (
The open end portion (9b) of 2) has a female stepped shape that fits into the female stepped shape.

In each of the above embodiments, the present invention has been explained in relation to butt welding of a pipe and a nozzle, but the present invention can also be implemented as a pipe groove shape when butt welding pipes together, and the groove can be changed to a conventional shape. It goes without saying that it may be implemented by providing it on the outer circumferential surface of the joint portion in the same manner as in the above, and that various modifications may be made without departing from the gist of the present invention.

According to the present invention, as described above, the open end of one pipe to be butt welded and the open end of the other pipe are shaped so that they can fit into q4. (I) Butt part (cutting angle) of the pipes Even if it is diagonal,
The pipe does not fall off during groove alignment or temporary welding, so groove alignment and temporary welding can be performed easily and accurately. Since no work space is required on the outer periphery of the IID vibrator, the welding work can be simplified, and other excellent effects can be achieved.

[Brief explanation of the drawing]

FIG. 1 is a sectional view showing an embodiment of the present invention, FIG. 2 and FIG.
The figure is a sectional view showing another embodiment of the present invention. (1)...pipe, (2)...nozzle, (3)...
Butt part, (4) (5)...Bevel, (6a) (66
) (aa) (86) (9α) (96) --- Open end, (7) -- Welding machine. Patent applicant Ishikawajima Harima Heavy Industries Co., Ltd. Patent applicant agent

Claims (1)

[Claims] 1) A pipe butt weld groove shape characterized in that the grooved end of one pipe to be butt welded has a female shape, and the opened end of the other pipe has a female shape that matches the female shape.