JPS5877774A - Method and device for build-up welding of internal surface of elbow pipe - Google Patents

Abstract

PURPOSE:To form a successive padding layer with uniform thickness on the internal surface of an elbow pipe by moving a welding torch opposed to one place of the internal wall surface of the elbow pipe with a weaving width proportional to the lengthwise width of the pipe. CONSTITUTION:Welding is carried on while a welder mount base 14 is moved to left or right at a specified speed from a position where a limit switch 12 is located at one end of a guide zone 10. When the switch 12 reaches the other end of the guide zone 10, a rotating shaft 2 is rotated by an extremely small angle through an angle detector, etc., using a timer or rotary pulse oscillator, etc., thus allowing an elbow pipe 1 to rotate slightly on its axis. Then, the base 14 is moved in the opposite direction to said motion and welding is carried on until the switch 12 reaches the end of the guide zone 10. Once the pipe 1 finishes making one turn on its own axis, an elastic lever 8 is extended or contracted to change weld zones, and said operation is repeated.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for overlaying the inner surface of an elbow pipe and an apparatus used therefor.

Conventionally, when applying a corrosion-resistant material to the inner surface of an elbow pipe, the lengths of both sides of the elbow pipe are different, so it is necessary to change the welding torch according to the change in length. Most of the Wii! This was done in a non-competitive way.

The present invention relates to a method and apparatus for continuously applying a build-up layer of uniform thickness to the inner surface of an elbow pipe, and the gist thereof is to form an elbow pipe with a center of each cross-sectional circle at the center of the central cross-section of the elbow pipe. In order to rotate about the tangent line that is in contact with the connecting central arc, and with the center of curvature of the elbow tube as the fulcrum, the center of the circle of one cross section of the elbow tube faces one place on the inner wall surface. Move at a riving speed and with a riving width that is proportional to the longitudinal width of the elbow pipe, and when the welding torch reaches the end of the riping width, the elbow t also moves one pipe around the upper axis. The welding torch is rotated by a certain angle, and then the welding torch is moved in the opposite direction to that described above to complete one round of welding.Then, the elbow tube is rotated about the above-mentioned fulcrum by an amount corresponding to the riving width. Elbow pipe inner wall surface welding method characterized by welding and welding M! There is a rotary plate whose axis is the middle jbF9 arc connecting the centers of each cross-sectional circle of the elbow pipe which is 41F & the tangent touching at the center of the central cross-sectional circle, and a rotary plate that protrudes on the rotary plate and has an elbow pipe at its tip. One end was pivotally supported on the pillar where the center of curvature was located, and the a-ratio center of the elbow tube on the same pillar, and the other end was movably connected to the expandable member installed on the disk. An elbow tube support device consisting of an elbow tube support body, and an elbow tube to be welded to a rotating shaft Rg1 that is synchronized with the rotation of the elbow tube to be welded.
A guide band consisting of a convex or concave band similar in shape to the shape of the part cut out by two radii extending at a certain angle from the center of the pipe is provided around the pipe, and the tip of the rod is placed on the guide band. This is a Nilpo W inner surface welding device consisting of a m-contact torch that is attached to or abuts a cross-section switch and moves forward and backward in response to the disturbance of the profiled material.

The present invention will be described in detail below with reference to the drawings. As shown in FIG. The elbow tube (1) is held so as to rotate around the tangent C-C tangent to the central arc BB connecting the centers of the cross-sectional circles, and any part of the elbow tube is held with the bending center 0 of the elbow tube as the center. It is held movably so that the center of the cross-sectional circle always moves on the BB. For that purpose, as shown in Figure 2, the elbow tube (1) is
! The extension of the line C-C in Figure T1 is on a straight line with the rotating shaft (2), and the fulcrum 0 in Figure 1 is the pillar (4) protruding from the rotating plate (3) and the elbow tube support. Axial fulcrum (6) with body (5)
) Hold the elbow tube (1) so that it is aligned with the Second
In the figure, (7) is an elbow tube holder, and (8) is a retractable member installed on the rotary plate, which is the elbow tube support (5).
The other end is movably supported.

Also, in the figure (9) is a synchronous rotating shaft that rotates in synchronization with the rotation of the elbow tube (1), (10) is a guide band, and this guide band is the third
As shown in Figure 4, the elbow pipe to be welded has a shape similar to that of the part cut by two radii extending at a certain angle from the center of curvature, as shown in Figure 4. Installed on the synchronous rotating shaft. (11) A welding torch (13) is attached to the tip of the side eave, and in response to the movement of this side eave (11) in the direction of the fan on the guide strip, a welding torch (13) is attached. The welding equipment mounting table (14), including the welding equipment mounting table (14), moves back and forth.

That is, the welding equipment mounting table (14) is moved to the first position from a place where the limit switch (12) is located at one end of the guide strip (10).
Do not move at a constant speed to the left or right in the figure.
Continue to connect the limit switch (12) to the guide band (10).
When the other end is reached, the elbow tube (
1) is rotated around Wakachi, and then 1! on the welding equipment mounting table (14). ! Set le in the opposite direction to the previous one and insert the limit switch (
The operation of welding is repeated until 12) reaches the end of the guide band (10).

When the elbow tube (1) completes one rotation,
The above-described operation is repeated by changing the part to be welded by expanding or contracting the extendable member (8).

As described above, according to the present invention, since welding is performed without changing the riping layer to match the elbow pipe to which the solution is to be applied, the thickness of the WI contact layer built up on the inner surface can be adjusted in some places. It does not vary depending on the thickness, and can be made to a uniform thickness, and can be applied to elbow pipes with various curvatures.
This can be solved by changing the distance from the center axis of rotation of the tube to the fulcrum as appropriate.

[Brief explanation of the drawing]

Figure m1 is an explanatory diagram showing the holding state of the elbow tube in the present invention, Figure 2 is a schematic diagram of the device of the present invention, Figure 3 is an explanation diagram of the development of the guide band, and Figure 4 is the main part of the synchronous rotating shaft. Explanatory diagram. In the figure, (1): Elbow tube (2): Rotating shaft (3): Rotating plate (6): Elbow tube support (9): Synchronous rotating shaft (10): Guide band (12): Limit switch (13) ): Welding torch patent applicant Kuroki Kogyo Co., Ltd. Agent Noriharu Ariyoshi

Claims (1)

[Claims] / In order to rotate the elbow tube about the tangent line that is in contact with the central arc connecting the centers of each cross-sectional circle at the center of its central cross-section,
and holding the center of a cross-sectional circle of the elbow tube so as to move on the central arc using the center of curvature of the elbow tube as a fulcrum,
A welding torch that faces one location on the inner wall surface of the elbow pipe is moved at a constant riving speed and with a riping width proportional to the longitudinal width of the elbow pipe (WIW)
-When the torch reaches the end of the riving width, rotate the elbow tube by a certain angle about the above-mentioned axis, and then move the welding torch in the opposite direction to the above-mentioned direction, repeating this process to complete one round of welding. and then welding is performed by rotating the elbow pipe by an amount corresponding to the riving width with the above-mentioned fulcrum as the middle zfp, and welding is performed. 2. A rotary plate whose axis is a tangent line that connects the centers of each cross-sectional circle of the elbow pipe, which is the object to be welded, and the center of the central cross-sectional circle, and an elbow protruding from the rotary plate at its tip. A column where the center of curvature of the tube is located, and an elbow on the same column.One end is pivotally supported on the column at the center of curvature of the tube, and the other end is movably connected to the telescopic structure installed on the disk. An elbow tube support device consisting of an elbow tube support body, which is a workpiece to be welded, is placed at a certain angle from the center of curvature of the elbow tube on the circumferential side of a rotating shaft that is synchronized with the rotation of the elbow tube, which is a workpiece to be welded. A guide band consisting of a convex or concave band similar in shape to the shape of the part cut out by the two radii extended by , a welding method for overlaying the inner surface of an elbow pipe, comprising a welding torch that moves forward and backward in response to the movement of the eaves.