JP2000329265A - Pipe having insertion port protrusion part and method for forming the protrusion part - Google Patents

Abstract

PROBLEM TO BE SOLVED: To facilitate formation of the protrusion part of the outer periphery of the insertion port of a cast iron pipe. SOLUTION: A plurality of protrusions 22 are formed at the outer periphery of the insertion port 11 of a pipe 10. A protrusion part ring 23 having an inner peripheral groove 26 in which the protrusion part 22 is fitted is fitted on externally of the insertion port 11. Further, by welding a plurality of pieces to the outer periphery of the insertion port 11 of the pipe 10, a plurality of the protrusions 22 are formed on the outer periphery of the pipe 10 and a protrusion ring having an inner peripheral groove 26 in which the protrusion 22 is fitted is externally fitted on in the insertion port 11.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

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

[0002]

2. Description of the Related Art In order to form a projection on the outer periphery of an insertion hole in a cut tube or the like, a projection ring is fitted on the outer periphery of the insertion hole and welded, for example, Japanese Patent Application No. 11-595.
No. 24. FIGS. 6 and 7 show a tube having an insertion projection of Japanese Patent Application No. 11-59524. That is, reference numeral 10 denotes a ductile cast iron pipe, in which an insertion port 11 is formed by a cut pipe, and a tapered surface 12 is formed on an outer periphery of the cut pipe portion. Insertion 11
Has a projection ring 13 fitted therein. The projecting ring 13 is formed of ductile cast iron or the like similar to the pipe 10, is formed in a circumferentially-divided configuration, and is tightly fitted to the insertion opening 11. The projection ring 13 has a tapered surface 14 that is continuous with the tapered surface 12 of the tube 10. The projecting ring 13 has a through hole 15 in the pipe diameter direction.
Are formed at equal pitches along the circumferential direction. The through-hole 15 is formed with a radially outward step 16.

[0003] A welding piece 17 is fitted into each through hole 15 of the projection ring 13. This welding piece 17
Is formed of an Fe-Ni-based alloy or the like, and has a step 18 which can be engaged with the step 16 of the projection ring 13 from the outside in the tube radial direction. In such a configuration, when a projection is formed on the outer periphery of the insertion opening 11, a projection ring 13 is mounted on the outer periphery of the insertion opening 11, positioned at a predetermined position, and temporarily fixed with an adhesive tape or the like. . Then, a welding piece 17 is attached to the through hole 15, and the welding piece 17 is welded to the outer surface of the insertion opening 11 by stud welding or the like. 19 is the welded portion. By attaching the welding pieces 17 to all of the through holes 15 and welding them to the outer surface of the insertion hole 11, a protrusion can be formed on the outer periphery of the insertion hole 11.

[0004]

However, in the case where the welding piece 17 is attached to the through hole 15 of the projecting ring 13 for welding as described above, the gap between the welding piece 17 and the projecting ring 13 is made at the time of welding. In some cases, the welding between the welding piece 17 and the insertion opening 11 may not be performed properly due to electric discharge or difficulty in centering the welding piece 17.

Accordingly, an object of the present invention is to solve such a problem and to easily form a projection on the outer periphery of the insertion opening.

[0006]

According to the present invention, a plurality of projections are formed on the outer periphery of an insertion opening of a pipe, and a projection ring having an inner peripheral groove into which the projections fit is inserted. It is made to fit in the mouth. Further, the present invention forms a plurality of projections on the outer circumference of the pipe by welding a plurality of pieces to the outer circumference of the insertion opening of the pipe, and inserts a projection ring having an inner circumferential groove into which these projections fit. It is an external fit.

Therefore, according to the present invention, a plurality of projections are formed by welding a piece directly to the outer periphery of an insertion opening of a pipe without intervention of a projection ring, and then the projection ring is fitted to the insertion opening. By fitting the protrusion into the inner circumferential groove,
The projection on the outer periphery of the insertion hole is easily formed as compared with the case where a piece is attached to the through hole of the projection ring and welded.

[0008]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, embodiments of the present invention will be described in detail with reference to FIGS. 1 to 5 by attaching the same reference numerals to the same members as those shown in FIGS. Will be described. As shown in FIGS. 1 and 2, an insertion port 11 is formed by a cut pipe of a cast iron pipe 10, and an end face 21 of the insertion port 11 is formed in a thickness direction thereof. A plurality of protrusions are formed at a plurality of positions at equal pitches along the circumferential direction on the outer periphery of the insertion hole 11 by welding the disc-shaped pieces 22 of a Fe-Ni-based alloy or the like at the welding portion 19. Have been.

A projection ring 23 is provided at the portion of the insertion opening 11 where the projection is formed by welding the piece 22.
Has been fitted. As shown in FIGS. 1 and 3, the protruding ring 23 is formed of the same ductile cast iron as the pipe 10, and has a circumferentially-divided configuration.
Numeral 24 is the dividing portion. A connection hole 25 is formed at each end of the division ring 24 in the circumferential direction of the projection ring 23. And the projecting ring 23 is a piece 22
Is configured to cover the outer surface of the end portion of the insertion opening 11 and the end surface 21. Also, the piece 22
The inner peripheral groove 26 having a rectangular cross section which is continuous in the circumferential direction and which can be fitted therein, and the outer peripheral taper surface 27 which replaces the taper surface at the tip of the insertion opening 11 are formed.

In such a case, the insertion opening 1 of the pipe 10
When a projection is formed on the outer periphery of the insertion surface 1, the end surface 2 of the insertion opening 11 having the end surface 21 as shown in FIGS.
The disc-shaped piece 22 is welded to a plurality of positions at a constant pitch in the circumferential direction along the outer circumference at a position at a fixed distance in the pipe axis direction from 1, for example, by stud welding. Each piece 22 is configured as a projection as described above, but corresponds to the inner peripheral groove 26 of the projection ring 23 when the insertion ring 11 is covered with the projection ring 23 as shown in FIG. To be welded at a predetermined position in the pipe axis direction.

However, the piece 22 can be welded to an arbitrary position in the circumferential direction of the insertion opening 11, and when welding to a position of a predetermined equal pitch fails, the failed piece is welded. For example, by shaving both ends of the tube 22 in the axial direction so as not to interfere with the inner peripheral groove 26 of the projecting ring 23, along the circumferential direction of the insertion opening 11 as shown by a virtual line in FIG. Another piece in another position 2
2 can also be welded. The piece 22 can be satisfactorily stud-welded by forming it into a disk shape as described above, but is not limited to this.
Any shape can be used as long as it fits into the inner peripheral groove 26 of the projection ring 23. For example, a rectangular cross section having a certain length in the circumferential direction may be used.

At this time, since the piece 22 is directly welded to the outer surface of the insertion opening 11 of the tube 10 without the intervention of the projection ring 23, discharge between the projection ring 23 and centering of the piece 22 is performed. Pieces 22 can be easily and reliably welded without causing a defect or the like. If a predetermined number of pieces 22 are welded to the outer periphery of the insertion port 11, then the projection ring 23 shown in FIG. By releasing, the piece 22 is fitted in the inner circumferential groove 26,
The protrusion ring 23 is formed between the outer surface of the end of the insertion port 11 and the end surface 21.
And cover. FIG. 4 shows the situation of the dividing unit 24 at this time.

Next, a dedicated connecting member 28 as shown in FIG.
If the connection and fixation are performed using a blind rivet or the like using the third connection hole 25, the formation of the insertion projection is completed. The fixing of the projection ring 23 to the insertion opening 11 can be performed by any appropriate means other than the fastening of the connecting member 28 as described above.

In the above description, the case where the insertion ring 11 having no tapered surface is covered with the projection ring 23 having the outer peripheral tapered surface 27 instead of the tapered surface of the insertion hole 11 has been described. In the same manner as the above, a configuration in which both the insertion opening 11 and the projection ring 23 have tapered surfaces may be adopted.

[0015]

As described above, according to the present invention, a plurality of projections are formed on the outer periphery of the insertion opening of the tube, and the projection ring having the inner peripheral groove into which these projections fit is fitted to the insertion opening. Also, by welding a plurality of pieces to the outer circumference of the insertion opening of the pipe, a plurality of projections are formed on the outer circumference of the pipe, and a projection having an inner circumferential groove into which these projections fit is provided. In order to fit the outer ring into the insertion hole, a plurality of protrusions are formed by welding pieces directly to the outer periphery of the insertion hole of the pipe without going through the projection ring, and then the projection ring is removed from the insertion hole. By fitting the protrusion into the inner circumferential groove, the protrusion on the outer periphery of the insertion hole can be formed easily compared to the conventional method of mounting and welding a piece in the through hole of the protrusion ring. Can be.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view of a main part of a pipe having an insertion projection according to an embodiment of the present invention.

FIG. 2 is a perspective view showing a state before a projection ring is fitted into an insertion opening of the pipe of FIG. 1;

FIG. 3 is an overall perspective view of a protrusion ring in FIG. 1;

FIG. 4 is a perspective view showing a state after a projection ring has been fitted into an insertion opening of the pipe of FIG. 1;

FIG. 5 is a view showing a state in which the protrusion ring of FIG. 4 is fixed to an insertion opening.

FIG. 6 is a cross-sectional view of a main part of a pipe having a conventional insertion projection.

FIG. 7 is an overall cross-sectional view of the tube of FIG. 6;

[Explanation of symbols]

 Reference Signs List 10 cast iron tube 11 insertion opening 22 piece 23 protruding ring 26 inner circumferential groove

 ────────────────────────────────────────────────── ─── Continuing from the front page (72) Inventor Naohisa Akiyama 2-26-2 Ohama-cho, Amagasaki-shi, Hyogo F-term in Kubota Mukogawa Works (reference) 3H111 AA01 BA02 CB27 CB28 DB03 DB05

Claims (2)

[Claims] 1. A plurality of projections are formed on an outer periphery of an insertion opening of a pipe, and a projection ring having an inner peripheral groove into which these projections are fitted is fitted into the insertion opening. A tube with a lip. 2. A plurality of pieces are welded to the outer circumference of an insertion opening of a pipe to form a plurality of projections on the outer circumference of the pipe, and a projection ring having an inner circumferential groove into which these projections fit is inserted. A method for forming an insertion projection, wherein the insertion projection is fitted to the mouth.