JP2002130559A - Formation method of raised portion at insertion opening of pipe - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide such a method that an insertion opening ring can be always and easily positioned on a fixed position when installing the insertion opening ring on a perimeter for forming a raised portion at an insertion opening of a pipe and heat deformation does not occur when welding the insertion opening ring on the insertion opening. SOLUTION: A tool 20 is formed so as to engage with a circular body 18 having no-divided part along circumferential direction and having a perimeter groove 19 along circumferential direction. The circular body 18 is fitted in an outside of the insertion opening 9 under closed fit by moving the circular body 18 along a pipe axis direction with the tool 20, and the circular body 18 is positioned in axis direction in respect to the pipe and fixed by contacting the tool 20 with top end face 9b of the insertion opening 9. Since the circular body 18 has not divided part in the circumferential direction, it is possible to prevent the heat deformation from production when welding the circular body 18 on the insertion opening 9.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for forming a tube insertion projection.

[0002]

2. Description of the Related Art As one type of pipe joint, there is a slip-on type pipe joint. This slip-on type pipe fitting is configured such that a receiving material and a receiving material can be joined by inserting a sealing material into the receiving material while compressing the sealing material into the receiving material. ing. An earthquake-resistant joint having the configuration shown in FIG. 4 has been proposed as a type of such a slip-on type pipe joint which is provided with an earthquake-resistant function.

That is, in FIG. 4, a receiving port 2 is formed at an end of one of the cast iron pipes 1 joined to each other.
An annular rubber sealing material 4 is disposed in the sealing material receiving groove 3 on the inner periphery of the receiving port 2, and a lock ring receiving groove 5 is formed on the back side of the sealing material receiving groove 3. 5 is provided with a lock ring 6 divided in the circumferential direction. Between the outer peripheral side of the lock ring 6 and the inner peripheral side of the lock ring accommodating groove 5, a holding rubber ring 7 for holding the lock ring 6 in a centered state when the insertion opening 9 is inserted is arranged. The holding rubber ring 7 is bonded, for example, to the outer periphery of the lock ring 6.

A projection 10 is formed on the outer periphery of the tip end of the insertion port 9 of the other cast iron tube 8 so as to engage the lock ring 6 from the back side of the receiving port 2. A tapered surface 11 serving as a guide when inserting the insertion port 9 into the receiving port 2 in which the sealing material 4 and the lock ring 6 are accommodated is provided on the outer periphery of the front end of the insertion port 9 including the protrusion 10. Is formed.

[0005] As shown in FIG. 5, the projection 10 is formed by welding an insertion ring 12 and an insertion ring 13 to an outer peripheral surface 9 a of the insertion opening 9. The insertion ring 12 and the insertion ring 13 have a split structure in the circumferential direction, and a tapered surface 12a is provided on the end surface of the insertion ring 12 on the distal end side of the insertion hole 9 as shown in FIG. Are formed. 14 is a weld bead. After welding, the tapered surface 12a of the insertion ring 12
The taper surface 11 is formed by processing the tip of the insertion opening 9 so as to form a smooth surface along the outer surface 10 of the projection 10.
ridge 1 of weld bead 14 to smooth a
4a is scraped off.

[0006] When forming the projection 10 of the insertion opening 9, FIG.
As shown in (c), the insertion ring 12 and the insertion ring 13 are mounted on the outer peripheral surface 9a of the insertion port 9. At this time, the insertion ring 13 is set so that the distance from the distal end surface 9b of the insertion opening 9 to the end surface 13a of the insertion ring 13 opposite to the distal end side of the insertion opening 9 has a specified dimension R, and The mouth ring 12 is mounted at a predetermined position at a distance from the insertion ring 13 so as to form a groove 15 into which molten metal can be poured when the insertion ring 12 and the insertion ring 13 are welded. You.

In order to weld the insertion ring 12 and the insertion ring 13 attached to the outer peripheral surface 9a of the insertion opening 9 to the outer peripheral surface 9a, a C-shaped shape as shown in FIG. Jig 16 having a tightening portion 16a at the opening of the C-shape
And a C-shaped shape as shown in FIG.
Fixing is performed using a fixing jig 17 having a fastening portion 17a at the opening of the character.

[0008] As shown in FIG.
6 is attached to a position having the above-mentioned specified dimension R, and the inner peripheral surface 17b of the fixing jig 17 is brought into close contact with the outer peripheral surface 13b.
By tightening the nut 17c of the tightening portion 17a shown in (b), the insertion ring 13 divided in the circumferential direction is fixed to the insertion opening 9. The insertion ring 12 is similarly brought into close contact with the inner peripheral surface 16b of the fixing jig 16 on the outer peripheral surface 12b of the insertion ring 12,
By tightening the nut 16c of the tightening portion 16a shown in FIG.
Fixed to.

Then, the welding device is brought close to the groove 15 between the insertion ring 12 and the insertion ring 13 fixed to the insertion hole 9 as described above, and the molten metal is poured into the groove 15 to perform the entire circumference welding. . Then, the insertion ring 12 and the insertion ring 1
3. Penetration occurs in the surface of the insertion opening 9, and the welding is completed as shown in FIG.

[0010]

In such a conventional structure, the insertion ring 12 and the insertion ring 13 are mounted on the outer peripheral surface 9a of the insertion port 9 to form the projection 10, and the fixing jig 16 is used. When the insertion ring 12 and the insertion ring 13 are fixed by the fixing jig 17, the insertion ring is aligned with a position where the distal end surface 9 b of the insertion 9 and the end surface 13 a of the insertion ring 13 form a specified dimension R. It is difficult to fix 13. Further, it is also difficult to set the position where the insertion ring 12 is fixed to a fixed position at a distance from the insertion ring 13 in order to form the groove 15. In addition, there is a possibility that deformation may occur in the vicinity of a portion where the insertion ring 12 and the insertion ring 13 are divided in the circumferential direction by thermal influence when the insertion ring 12 and the insertion ring 13 are welded to the outer peripheral surface 9 a of the insertion hole 9. There is also.

Accordingly, the present invention solves such a problem, and when the insertion ring for forming the insertion projection of the pipe is mounted on the outer peripheral surface of the insertion port, it is always in a fixed position and easily. An object of the present invention is to make it possible to perform positioning at a predetermined position and to prevent thermal deformation of the insertion ring when welding the insertion ring to the insertion hole.

[0012]

SUMMARY OF THE INVENTION In order to solve the above-mentioned problems, according to the first aspect of the present invention, a jig is mounted on an annular body having no circumferential divided portion and having an outer circumferential groove along the circumferential direction. In addition, by moving the annular body in the pipe axis direction by the jig, the annular body is fitted to the pipe in an interference fit state, and the jig is brought into contact with the distal end surface of the pipe to thereby form the annular body. Is positioned in the axial direction with respect to the pipe, the jig is removed, the groove bottom of the annular body is removed, the outer peripheral surface of the pipe is exposed, and welding is performed in the groove to integrate the annular body with the pipe. It is characterized by the following.

According to such a configuration, when the jig is engaged with the annular body and the annular body is fitted to the outer periphery of the pipe in a tight fit, the jig is brought into contact with the tip of the pipe. The position of the annular body at that time, that is, the position where the annular body is most moved in the tube axis direction by the jig is the position where the annular body is to be positioned. In this way, the annular body can be easily positioned by bringing the jig into contact with the tip of the tube, and since the annular body is fitted in the above-mentioned interference fit state, the annular body can be easily removed. This eliminates the need for fixing.

Since the annular body used to form the insertion projection is not divided in the axial direction, the positioning and fixing of the annular body can be easily performed. Furthermore, since this annular body has a structure having no divided portion in the circumferential direction,
It is possible to eliminate thermal deformation that occurs when the annular body is welded to the pipe.

[0015]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS As shown in FIG.
Ring 1 for forming an insertion projection by being externally fitted
8 is provided with an outer peripheral groove 19 along the circumferential direction, and the cross-sectional shape of the insertion ring 18 in the axial direction is concave. 19a is a groove bottom. A taper surface 18b is provided on the outer periphery of the distal end portion 18a of the insertion opening 9 in the insertion ring 18, and a tapered surface 18b is provided radially outward on a rear side portion 18c separated from the distal end portion 18a by an outer circumferential groove 19. Protruding part 18d
Are provided in the circumferential direction.

The projection 1 as shown in FIG.
In order to form 0, the insertion ring 18 is fitted over the outer peripheral surface 9a of the insertion hole 9, but the inside diameter of the insertion ring 18 is set so that the insertion ring 18 is tightly fitted to the insertion hole 9. 9 is configured to be slightly smaller than the outer diameter. For this purpose, a fitting jig 20 is used. Further, since the insertion opening 9 is a cast product, its outer diameter may be slightly different within a dimensional tolerance.
In order to cope with a change in the outer diameter of the insertion hole 9 within this dimensional tolerance, it is desirable to prepare at least three types of insertion rings 18 from a small inner diameter to a larger one.

The fitting jig 20 is a bottomed cylindrical body having a U-shaped cross section in the axial direction. The inner diameter of the fitting jig 20 is large enough to allow the distal end portion 18a to enter. The projection 18d of the rear side portion 18c is configured such that the projection 18d cannot enter.
The end face 20a on the side of the opening portion of 0 is configured to engage with the projection 18d.

As shown in FIG. 1A, the insertion ring 18 is inserted into the fitting jig 20, and the fitting jig 2
In a state where the end face 20a of the “0” and the projection 18d of the insertion ring 18 are engaged with each other, the insertion ring 18 is fitted to the outer peripheral surface 9a of the insertion port 9 in an interference fit state.

As shown in FIG. 1B, the insertion ring 18 is fitted in the tube axis direction of the insertion port 9 until the inner end face 20b of the fitting jig 20 contacts the front end face 9b of the insertion port 9. . When the inner end face 20b of the fitting jig 20 comes into contact with the tip end face 9b of the insertion port 9, the distance from the inner end face 20b of the fitting jig 20 to the end face 18e of the insertion ring 18 opposite to the tapered face 18b is opposite. The distance is the specified dimension R shown in FIG. 6C and described above. Since the insertion ring 18 is fitted over the insertion hole 9 in a tightly fitted state, it is positioned and fixed at this position.

As shown in FIG. 2 (a), the fitting jig 20 is removed, and as shown in FIG. 2 (b), the groove bottom 19a of the outer peripheral groove 19 is scraped off with a sander 21, and the outer peripheral surface of the insertion opening 9 is removed. 9a is exposed.

As shown in FIG. 2C, the protrusion 18d of the insertion ring 18 is scraped off with a sander 21, and the insertion ring 1 is removed.
8 is made to have a smooth outer peripheral surface as shown in FIG. The insertion ring 18 is connected to the insertion ring 9 by using 22 shown in FIG.
To weld. As shown in FIGS. 3A and 3B,
The welding device 22 is configured by attaching a carriage 24 to which a welding torch 23 is attached to a rail 25 fixed to the outer periphery of the insertion opening 9.

The rail 25 has an assembling structure divided in the circumferential direction. The rail 25 is provided with a push bolt 26 which is screwed inward. The rail 25 is concentrically fixed to the insertion port 9 by pressing the outer peripheral surface 9 a of the insertion port 9 with the tip of the push bolt 26.

The carriage 24 is provided with a roller 27. The roller 27 sandwiches the rail 25 from the inside and outside in the radial direction, and movably supports the carriage 24 on the rail 25 without falling off the rail 25. ing.

The carriage 24 includes a drive-type pinion 28.
Is provided, and a rack 29 that meshes with the drive pinion is provided in the circumferential direction of the rail 25.
The carriage 24 is configured to be able to travel along the outer periphery of the insertion slot 9 without causing slip on the rail 25.

Using the welding apparatus 22 having the above structure, FIG.
As shown in (a), the molten metal 30 when the insertion ring 18 is welded to the insertion hole 9 is poured into the outer peripheral groove 19 along the circumferential direction, and is welded in a state as shown in FIG. And the insertion ring 18 are integrated.

[0026]

As described above, according to the present invention, the jig is engaged with the annular body used to form the insertion projection, and the annular body is fitted over the outer periphery of the pipe in a tightly fitted state. At this time, the position of the annular body when the jig is brought into contact with the tip of the pipe,
That is, the position where the annular body is moved most in the tube axis direction by the jig is the position where the annular body is to be positioned. In this way, the annular body can be easily positioned by bringing the jig into contact with the tip of the tube, and since the annular body is fitted in the above-mentioned interference fit state, the annular body can be easily removed. This eliminates the need for fixing.

Since the annular body is not divided in the axial direction, the positioning and fixing of the annular body can be easily performed. Further, since the annular body has a structure having no divided portion in the circumferential direction, it is possible to eliminate thermal deformation generated when the annular body is welded to the pipe.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view showing a method of forming an insertion projection according to an embodiment of the present invention.

FIG. 2 is a cross-sectional view of the vicinity of the insertion projection showing a method of forming the insertion projection according to the embodiment of the present invention.

FIG. 3A is a side view of a welding device for welding an insertion ring to an insertion hole, and FIG. 3B is a front view of the welding device.

FIG. 4 is a cross-sectional view illustrating a pipe joint using a pipe having an insertion projection.

FIG. 5 is a cross-sectional view of the vicinity of an insertion projection when an insertion ring is welded to the insertion opening.

FIG. 6 is a diagram illustrating a conventional method for forming an insertion projection.

[Explanation of symbols]

 Reference Signs List 9 insertion opening 9a outer peripheral surface 9b tip end surface 18 insertion ring 19 outer peripheral groove 19a groove bottom 20 fitting jig 30 molten metal

Claims (1)

[Claims] 1. A jig is engaged with an annular body having no circumferential divided portion and having an outer circumferential groove along the circumferential direction, and the annular body is moved in the pipe axis direction by the jig.
The annular body is fitted to the pipe in an interference fit state, and the jig is brought into contact with the distal end surface of the pipe to position the annular body in the axial direction with respect to the pipe. The jig is removed, and the annular body is removed. Removing the bottom of the groove, exposing the outer peripheral surface of the tube, welding the inside of the groove, and integrating the annular body into the tube.