JPH08233170A - Breakaway preventing pipe joint - Google Patents

Abstract

PURPOSE: To let a slip-on type pipe joint be endowed with a breakaway preventing function with no ring shaped groove formed at the outer circumference of a spigot. CONSTITUTION: A projected section 18 in a rectangular shape in cross section is welded in the outer circumference of a spigot 14 at the outside of a socket 12, and a brim section 17 is thereby formed in the outer circumference at the opening section of the socket. A first lock ring 28 capable of being engaged with the brim section 17, is fitted in the first ring shaped groove 24 of a ring shaped housing 21. A second lock ring 32 capable of being engaged with the projected section 18 by fastening the ring itself to the outer circumferential surface of the spigot 14, is fitted in the second ring shaped groove 25 of the housing 21. The second lock ring 32 side at the projected section 18 is formed into a bevel welded structure. A cut-out section 39 capable of housing welding beads formed by the bevel welding of the projected section 18 is formed in the inner circumference of a section engaged with the projected section 18 at the second lock ring 32.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a separation prevention pipe joint.

[0002]

2. Description of the Related Art As a type of pipe joint, there is known one in which an annular sealing material is compressed between an inner surface of a receiving port and an outer surface of an insertion port. With this pipe joint, simply insert the insertion port inside the receiving port with the annular sealing material in the receiving port.
It is called a slip-on type pipe joint because it can exert a predetermined sealing function by compressing the sealing material between the receiving and inserting ports.

This slip-on type pipe joint has a sufficient expansion / contraction function because it has a construction in which the insertion port is inserted into the receiving port and the sealing material is compressed as described above.
However, in some cases, it may be desirable to provide a slip-on type pipe fitting with a separation prevention function that prevents expansion and contraction.In such a case, an annular groove is formed on the inner circumference of the receiving opening and the outer circumference of the insertion opening. In general, the lock ring is engaged with the both annular grooves.

[0004]

However, when the annular groove is formed on the outer periphery of the insertion port, the wall thickness is reduced accordingly, so that the strength is lowered and the sealing performance between the receiving port and the insertion port is also reduced. It has a problem that it may have an adverse effect.

SUMMARY OF THE INVENTION Therefore, an object of the present invention is to solve such a problem and to provide a slip-on type pipe joint with a separation preventing function without forming an annular groove on the outer periphery of the insertion opening. And

[0006]

In order to achieve this object, the present invention provides a pipe joint for compressing an annular sealing material between the inner surface of the receiving opening and the outer surface of the receiving opening. An annular protrusion having a rectangular cross section is welded to the outer periphery to form a brim on the outer periphery of the opening of the receiving opening, and the brim is passed from a position farther from the receiving opening than the protruding portion of the insertion opening. And a first annular groove is formed on the inner circumference of the housing at a position corresponding to the receiving portion beyond the flange portion in the housing. A first lock ring engageable with the collar is fitted in the annular groove, and a second annular groove is formed on the inner periphery of the housing at a position farther from the receiving port than the protrusion, and In the second annular groove,
By fitting a second lock ring having a rectangular cross section that can engage with the protrusion by tightening on the outer peripheral surface of the insertion slot,
The second lock ring side of the protrusion has a groove welding structure, and the weld bead of the groove welding of the protrusion can be accommodated on the inner circumference of the engaging portion of the second lock ring with the protrusion. The cutout portion is formed.

[0007]

According to this structure, the first lock ring fitted in the first annular groove of the housing engages with the flange portion of the receiving opening, and also fits in the second annular groove of the insertion opening. The second lock ring, which is tightened on the outer peripheral surface, engages with the protrusion of the insertion slot, so that a separation prevention function is provided between the socket insertion slots. At that time, since the annular protrusion is simply welded to the outer periphery of the insertion opening, a required separation preventing function is provided without forming an annular groove on the outer periphery of the insertion opening. Further, the second lock ring side of the protrusion has a groove welding structure, and the weld bead of the groove welding of this protrusion can be accommodated on the inner circumference of the engaging portion of the second lock ring with the protrusion. Since the notch portion is formed, it is possible to engage with the second lock ring even if the protrusion is formed to be low in the radial direction. Therefore, it is possible to reduce the size of the protrusion and the second lock ring that engages with the protrusion.

[0008]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS As shown in FIG. 1, a receiving port 12 is formed at the end of one cast iron pipe 11 to be joined to each other, and a receiving port 12 is provided at the end of the other cast iron pipe 13. Inserted inside 14
Are formed. A sealant accommodating portion 15 is provided on the inner circumference of the receiving port 12.
The sealing material 16 accommodated in the sealing material accommodating portion 15 is formed by inserting the insertion opening 14 into the receiving opening 12.
By being compressed between the inner surface of 12 and the outer surface of the insertion port 14,
It is configured to have a predetermined sealing function.
A collar 17 is formed on the outer periphery of the opening of the receiving port 12.

An annular projection 18 having a rectangular cross section is fitted on the outer periphery of the insertion opening 14 outside the receiving opening 12 and fixed by welding. 9 and 10 are the weld beads. The protrusion 18 is configured to be located near the opening end face 20 of the receiving opening 12 when the insertion opening 14 is inserted to a predetermined position inside the receiving opening 12.

From the outer peripheral portion of the receiving port 12 beyond the brim portion 17,
The annular housing 21 made of cast iron is externally fitted over the range from the projection 18 of the insertion opening 14 inserted to a predetermined position inside the receiving opening 12 to the outer peripheral portion of the position farther from the receiving opening 12. There is. In this housing 21, a receiving side inner peripheral surface 22 having a diameter slightly larger than that of the flange portion 17 is formed in a portion fitted into the receiving opening 12, and a portion fitted in the inserting opening 14 is fitted. At the insertion side inner peripheral surface 23, which has a diameter slightly larger than that of the protrusion 18,
Are formed. The collar portion 17 on the inner peripheral surface 22 on the receiving side
A first annular groove 24 in the circumferential direction is formed at a position corresponding to the receiving portion beyond. Further, a second annular groove 25 in the circumferential direction is formed on the insertion-side inner peripheral surface 23 at a position farther from the receiving opening 12 than the protruding portion 18. Each of the first and second annular grooves 24, 25 is formed in a rectangular cross section.

A first annular groove formed on the inner peripheral surface 22 of the receiving side
A first lock ring 28 is accommodated in 24. The first lock ring 28 has a rectangular horizontal cross section and is formed in one division in the circumferential direction. First set bolts 29 screwed in the pipe radial direction from the outer surface of the housing 21 toward the first annular groove 24 are arranged at a plurality of positions in the circumferential direction. This first set bolt 29 is formed with a hexagonal hole without a head, and by pressing the outer surface of the first lock ring 28 with its outer end screwed into the housing 21, this first set bolt 29 is Keep the lock ring 28 of No. 1 in a tight state and receive it
It is possible to hold it on the outer peripheral surface 30 of 12. When the first lock ring 28 is thus tightened on the outer peripheral surface 30 of the receiving port 12, the first lock ring 28 can engage with both the first annular groove 24 and the flange portion 17 in the pipe axial direction. Become.

A second annular groove formed on the inner peripheral surface 23 on the insertion side
A second lock ring 32 is accommodated in 25. Similar to the first lock ring 28, the second lock ring 32 has a rectangular transverse cross section and is formed in a circumferential direction.
Then, like the above-mentioned first lock ring 28, a headless hexagonal hole in which the outer end of the housing 21 is screwed in the pipe radial direction toward the second annular groove 25 and the outer end is screwed into the housing 21. By the action of a plurality of second set bolts 37 in the circumferential direction, the insertion state is maintained in a tight state.
It is held on the outer peripheral surface of 14. This second lock ring
When the outer peripheral surface of the insertion opening 14 is thus tightened, the 32 can engage with both the second annular groove 25 and the protrusion 18 in the pipe axial direction.

As shown in FIGS. 1 and 2, regarding the welding structure of the projection 18 to the insertion opening 14, the portion of the projection 18 on the receiving opening 12 side is welded to the insertion opening 14 by fillet welding. There is. On the other hand, the second lock ring 32 in the protrusion 18
A welded structure with a groove is used for the side portion. Therefore, the weld bead 10 on the second lock ring 32 side can be formed smaller than the weld bead 9 on the receiving port 12 side. Therefore, even if the height of the protrusion 18 is reduced, it is possible to form the engagement end face 38 capable of achieving the required engagement with the second lock ring 32. Moreover, the second lock ring 32 correspondingly
The height of the second lock ring 32 and the protrusion 18 can be made small. Further, when the second lock ring 32 is formed in a small size, its rigidity does not become so strong, and the second annular groove 25 of the housing 21 is not formed.
Can be easily installed. A tapered notch 39 capable of accommodating the weld bead 10 is formed on the inner periphery of the second lock ring 32 on the side of the protrusion 18.

That is, if fillet welding is performed on both sides of the protrusion 18 as shown in FIG.
Since 41 becomes large, the height of the protrusion 18 must be correspondingly increased in order to form a required engaging end surface. In addition, the second lock ring 32 must be enlarged correspondingly, which causes a drawback that the projection 18 and the second lock ring 32 become large in size. In addition, if the second lock ring 32 becomes large in size, its rigidity becomes strong, and it becomes difficult or impossible to mount it in the second annular groove 25.

When joining the joints, with the second lock ring 32 mounted in the second annular groove 25 of the housing 21, the housing 21 is moved to a position where the second lock ring 32 exceeds the protrusion 18. Cover the insertion slot 14. Further, the sealing material 16 is previously stored in the storage portion 15 of the receiving port 12.

Next, the first lock ring 28 is housed in the first annular groove 24 of the housing 21 mounted in the insertion opening 14, and then the insertion opening 14 is inserted into the receiving opening 12. Then, the sealing material 16 is compressed between the outer peripheral surface of the insertion opening 14 and the inner peripheral surface of the housing portion 15 of the receiving opening 12, and a required sealing function is provided between the receiving opening and the insertion opening. Then, if the flange portion 17 of the receiving opening 12 is fitted to a position corresponding to the receiving-side inner peripheral surface 22 on the inner side of the first lock ring 28, at that time, the first lock in the annular groove 24. Receptacle for the part where the ring 28 exceeds the brim 17
Since it is positioned corresponding to the outer peripheral surface 30 of 12, the first lock ring 28 is received by the first set bolt 29 as shown in the drawing.
Tighten the outer peripheral surface 30 of 12. Moreover, the second lock ring 32 is tightened on the outer peripheral surface of the insertion opening 14 with the second set bolt 37.

Then, the first lock ring 28 engages with both the first annular groove 24 of the housing 21 and the flange portion 17 of the receptacle 12, and the second annular groove 25 fitted in the second annular groove 25. The lock ring 32 has an engaging end surface of the second annular groove 25 and the protrusion 18.
By engaging with 38, a predetermined separation prevention function is provided between the receiving opening 12 and the insertion opening 14.

By doing so, a separation preventing function can be imparted without forming an annular groove on the outer periphery of the insertion opening 14, and the separation can be carried out without causing a problem in the strength and sealing property of the joint portion. A preventive function can be added. Further, as described above, the welding structure in which the groove is provided in the portion of the protrusion 18 on the side of the second lock ring 32 is adopted, and as a result, the welding bead 10 can be formed small and the protrusion 18 Also, the second lock ring 32 can be constructed in a small size, and the rigidity of the second lock ring 32 can be suppressed to a low level, so that the second lock ring 32 can be easily mounted in the second annular groove 25 of the housing 21.

[0019]

As described above, according to the present invention, the flange portion of the receiving opening is formed in the first annular groove and the second annular groove of the housing which are fitted by fitting over the receiving opening. Since the first lock ring that can engage with the first lock ring and the second lock ring that can engage with the annular protrusion welded to the outer periphery of the insertion opening outside the receiving opening are engaged with each other, Not only can a separation prevention function be provided between the receiving and inserting openings without forming an annular groove for accommodating the lock ring on the outer periphery, but also the second lock ring side of the protrusion is groove welded. In addition to having a structure, a notch capable of accommodating the welding bead of the groove welding in the protrusion is formed in the inner circumference of the engaging portion of the second lock ring with the protrusion, so that the protrusion is radially formed. Engages with the second lock ring, even if formed low Bets can be, Therefore, the this projection,
The second lock ring that engages with this protrusion can be downsized, and by downsizing, the rigidity of the second lock ring can be lowered, and this second lock ring can be easily made. It can be fitted into the second annular groove.

[Brief description of drawings]

FIG. 1 is a sectional view of a separation prevention pipe joint according to an embodiment of the present invention.

FIG. 2 is a diagram illustrating the engagement between a protrusion and a second lock ring in FIG.

FIG. 3 is a diagram showing a comparative example of engagement between a protrusion and a second lock ring.

[Explanation of symbols]

 10 Weld bead 12 Receptacle 14 Insertion mouth 17 Collar 18 Protrusion 21 Housing 24 First annular groove 25 Second annular groove 28 First lock ring 32 Second lock ring 39 Notch

Claims (1)

[Claims] 1. A pipe joint for compressing an annular sealing material between an inner surface of a receiving opening and an outer surface of an insertion opening, wherein an annular projection having a rectangular cross section is welded to the outer periphery of the insertion opening outside the receiving opening. ,
A collar portion is formed on the outer circumference of the opening of the receiving opening, and an annular housing is provided which is fitted over the receiving portion beyond the flange from a position farther from the receiving opening than the protruding portion of the insertion opening. A first annular groove is formed on the inner periphery of the housing at a position corresponding to the receiving portion beyond the brim portion, and the first annular groove is capable of engaging with the brim portion. A lock ring is fitted to form a second annular groove in the inner periphery of the housing at a position farther from the receiving portion than the protrusion, and the second annular groove is fastened to the outer peripheral surface of the insertion opening. With this, a second lock ring having a rectangular cross-section capable of engaging with the protrusion is fitted, and the second lock ring side of the protrusion has a groove welding structure, and the protrusion of the second lock ring is formed. Part of the relationship with the department The circumferential, separation preventing fitting, characterized in that the formation can accommodate Ketsuto section weld bead groove welding in the projection.