JP7049871B2 - Pipe fittings and pipe joining methods - Google Patents

Description

The present invention relates to a pipe joint having a detachment prevention function and a method for joining a pipe.

Conventionally, as a pipe joint of this type, for example, as shown in FIG. 22, the insertion port 104 of the other pipe 103 is inserted into the receiving port 102 of one pipe 101, and the lock ring accommodating groove is formed on the inner circumference of the receiving port 102. 105 is formed, the lock ring 106 is accommodated in the lock ring accommodating groove 105 and fitted into the insertion port 104, and an outer peripheral protrusion 107 protruding outward in the pipe radial direction is formed on the outer periphery of the insertion port 104 to form an outer periphery. Some have a detachment prevention function that prevents the insertion port 104 from being pulled out from the receiving port 102 by engaging the protrusion 107 with the lock ring 106 from the back side of the receiving port 102.

The lock ring 106 is a ring having a split structure having a divided portion 108 (see FIG. 25) at one location. An elastic member 109 that presses the lock ring 106 inward in the pipe radial direction 114 is provided between the outer peripheral surface of the lock ring 106 and the bottom surface of the lock ring accommodating groove 105. As shown in FIG. 23, the elastic member 109 is a rubber annular member, and has a plate-shaped body 110 and a protruding body 111 protruding inward 114 in the pipe radial direction from the plate-shaped body 110. There is.

The method of joining the pipes 101 and 103 of the pipe joint 100 as described above will be described below.

First, the elastic member 109 is fitted into the lock ring accommodating groove 105 of the receiving port 102 of one of the pipes 101. Next, the lock ring 106 is housed on the inner peripheral side of the elastic member 109 in the lock ring accommodating groove 105. At this time, the divided portion 108 of the lock ring 106 is directed toward the bottom of the pipe.

Next, as shown in FIGS. 24 and 25, a plurality of mantis shrimp vices 112 are hung on the opening end of the receiving port 102 to expand the diameter of the lock ring 106. At this time, the diameter of the lock ring 106 is expanded to the extent that the inner peripheral surface of the lock ring 106 is flush with the inner peripheral surface of the receiving port 102. The mantis shrimp 112 is set at a plurality of locations along the circumferential direction of the lock ring 106.

With the expansion of the diameter of the lock ring 106 as described above, the divided portion 108 of the lock ring 106 is also expanded in the circumferential direction, and the elastic member 109 in the lock ring accommodating groove 105 is compressed in the pipe radial direction 115.

Next, a diameter reduction prevention stopper (not shown) is fitted into the enlarged divided portion 108, whereby the lock ring 106 is kept in the enlarged diameter state. After that, all the mantis shrimp vise 112 are removed from the socket 102. At this time, since the lock ring 106 is kept in the enlarged diameter state by the diameter reduction prevention stopper, the inner peripheral surface of the lock ring 106 is flush with the inner peripheral surface of the receiving port 102.

Next, the insertion port 104 is inserted into the lock ring 106 and the receiving port 102, and the outer peripheral protrusion 107 is passed through the lock ring 106 from the opening end 116 side of the receiving port 102 to the back side of the receiving port 102.

After that, the diameter reduction prevention stopper is removed from the divided portion 108 of the lock ring 106 to reduce the diameter of the lock ring 106, so that the lock ring 106 has its own elastic force and the pressing force of the elastic member 109 to reduce the outer diameter of the insertion port 104. Hugging to.

The pipe joint and the pipe joining method as described above are described in, for example, Patent Document 1 below.

JP 2006-70994

However, in the above-mentioned conventional form, as shown in FIGS. 24 and 25, when the diameter of the lock ring 106 is expanded by using the mantis shrimp 112, the elastic member 109 in the lock ring accommodating groove 105 becomes a tube. It is compressed over the entire circumference in the radial direction 115. At this time, the lock ring 106 is pressed inward 114 in the pipe radial direction over the entire circumference by the repulsive force of the compressed elastic member 109. Therefore, a large amount of force is required to expand the diameter of the lock ring 106, a large number of mantis shrimp vices 112 are required, and there is a problem that the joining work of the pipes 101 and 103 requires labor and labor.

An object of the present invention is to provide a pipe joint and a pipe joining method that can reduce the labor and labor required for the pipe joining work.

In order to achieve the above object, in the first invention, the insertion port of the other tube is inserted into the receiving port of one tube.
A lock ring accommodating groove is formed on the inner circumference of the receiving port,
The lock ring is housed in the lock ring housing groove and fitted outside the insertion slot.
An outer peripheral protrusion is formed on the outer periphery of the insertion port so as to project outward in the radial direction of the pipe.
A pipe joint having a detachment prevention function that prevents the insertion port from being removed from the receiving port by engaging the outer peripheral protrusion with the lock ring from the insertion / removal direction of the insertion port.
A pressing member for pressing the lock ring inward in the radial direction is provided between the outer peripheral surface of the lock ring and the bottom surface of the lock ring accommodating groove.
The pressing member has a plurality of pressing bodies arranged at predetermined intervals in the tube circumferential direction, and a plurality of spacing holding bodies that maintain the spacing between adjacent pressing bodies in the tube circumferential direction .
The end of the pressing body in the circumferential direction of the pipe and the end of the spacing holding body are detachably connected by a connecting member.
The pressing body abuts on the outer peripheral surface of the lock ring and presses the lock ring inward in the radial direction of the pipe.

According to this, the pressing body of the pressing member abuts on the outer peripheral surface of the lock ring and presses the lock ring inward in the pipe radial direction, so that the lock ring clings to the outer periphery of the insertion slot.

When a detachment force acts on the insertion port due to an earthquake or the like and the insertion opening moves in the removal direction with respect to the receiving port, the outer peripheral protrusion engages with the lock ring from the back side of the receiving port, thereby inserting. It is possible to prevent the mouth from coming off the receiving port.

When joining the pipes, first, the pressing body and the space holding body are connected by a connecting member and fitted into the lock ring accommodating groove of the receiving port, whereby the pressing member is easily formed and fitted into the lock ring accommodating groove. be able to. After that, the lock ring is fitted into the lock ring accommodating groove, and the diameter of the lock ring is expanded by using a jig for expanding the diameter such as a mantis shrimp to resist the inward pressing force in the pipe radial direction by the pressing body of the pressing member. do.

At this time, the lock ring is pressed inward in the pipe radial direction by a plurality of pressing bodies of the pressing member, but these pressing bodies are not arranged over the entire circumference of the pressing member, but are predetermined in the tube circumferential direction. They are arranged at intervals. Therefore, the lock ring is pressed inward in the pipe radial direction at a plurality of locations spaced apart in the pipe circumferential direction, and is not pressed inward in the pipe radial direction over the entire circumference.

As a result, the number of diameter-expanding jigs such as mantis shrimp vise required for expanding the diameter of the lock ring can be reduced, and the labor and labor required for the pipe joining work can be reduced.

In the pipe joint in the second invention , when the pressing body presses the lock ring, both ends of the pressing body in the tube circumferential direction are pressed against the bottom surface of the lock ring accommodating groove via the connecting member, and in this state, pressing is performed. The body is deformed into an arc shape that bulges outward in the radial direction of the pipe with both ends as fulcrums .

In the pipe joint in the third invention, the lock ring is a ring having a split structure having a divided portion at one place.

According to this, when joining pipes, first, the pressing body and the space holding body are connected by a connecting member and fitted into the lock ring accommodating groove of the receiving port to form the pressing member, and then the lock ring accommodating. The lock ring is fitted into the groove, and the diameter of the lock ring is expanded against the inward pressing force in the pipe radial direction by the pressing body of the pressing member by using a jig for expanding the diameter such as a shako vise.

After that, the diameter reduction prevention stopper is sandwiched between the divided parts of the lock ring to keep the lock ring in an expanded state, the insertion port is inserted into the lock ring and the receiving port, and the outer peripheral protrusion is inserted into the receiving port with respect to the lock ring. Pass from the opening end side to the back side of the socket.

After that, the diameter reduction prevention stopper is removed from the divided portion of the lock ring to reduce the diameter of the lock ring. As a result, the lock ring is pressed inward in the pipe radial direction by the pressing body of the pressing member, so that the lock ring is held on the outer periphery of the insertion port by its own elastic force and the pressing force from the pressing body.

In the pipe joint in the fourth invention, the pressing body is a metal plate, and the pressing body is a metal plate.
The spacing holder is a flexible resin plate.

The fifth invention is the method for joining pipes of a pipe joint according to the third invention.
A plurality of pressing bodies and spacing holders are fitted into the lock ring accommodating groove of the receiving port to form a pressing member.
Fit the lock ring into the lock ring storage groove and
Enlarge the diameter of the lock ring and put a diameter reduction prevention stopper in the divided part of the lock ring to keep the lock ring in the expanded state.
The insertion port is inserted into the lock ring and the receiving port, and the outer peripheral protrusion is passed through the lock ring from the opening end side of the receiving port to the back side of the receiving port.
The diameter reduction prevention stopper is removed from the divided portion of the lock ring to reduce the diameter of the lock ring.

As described above, according to the present invention, when joining the pipes, the lock ring is pressed inward in the pipe radial direction at a plurality of locations spaced apart in the pipe circumferential direction, and is inward in the pipe radial direction over the entire circumference. Since it is not pressed, the number of jigs for diameter expansion such as shako vise required to expand the diameter of the lock ring can be reduced, and the labor and labor required for pipe joining work can be reduced. be able to.

It is sectional drawing of the pipe fitting in embodiment of this invention. The same is a cross-sectional view of the receiving port of the pipe joint. It is a figure of the seal member of a pipe joint, and a part thereof is shown in cross section. It is the figure of the push ring of the pipe joint. It is the figure of the lock ring of the pipe fitting. The same is the cross-sectional view when the pressing member is fitted into the lock ring accommodating groove of the pipe joint. It is an enlarged view of a part of FIG. The same is an enlarged perspective view of a part of the pressing member of the pipe joint. The same is an enlarged perspective view of a part of the pressing member of the pipe joint. It is the figure which showed typically the cross section when the pressing member and the lock ring were fitted into the lock ring accommodating groove of the pipe joint, the insertion opening was inserted into the receiving opening, and the pipes were joined to each other. It is an enlarged view of a part of FIG. It is the cross-sectional view which shows the joining method of the pipe of the pipe joint, and shows the state which the push ring, the lock ring and the pressing member are inserted in the receiving port. The same is a cross-sectional view showing a method of joining a pipe of a pipe joint, and shows a state in which the diameter of the lock ring is expanded by using a mantis shrimp vise. It is the figure which shows the joining method of the pipe of the pipe joint, and shows the state which the diameter of the lock ring was expanded by using the mantis shrimp vise. It is the figure which shows the joint method of the pipe of the pipe joint, and shows the state which the stopper for diameter reduction prevention was fitted in the divided part of the lock ring. The same is a cross-sectional view showing a method of joining a pipe of a pipe joint, showing a state in which a stopper for preventing diameter reduction is fitted into a divided portion of a lock ring. It is a perspective view of the stopper for preventing diameter reduction used at the time of joining a pipe of a pipe joint. The same is a cross-sectional view showing a method of joining pipes of a pipe joint, showing a state in which an insertion port is inserted into a receiving port and a sealing member is deposited in the receiving port. The same is a cross-sectional view showing a method of joining a pipe of a pipe joint, and shows a state in which the distance between the push ring and the back end surface of the receiving port is expanded by using an expansion jig. The same is a cross-sectional view showing a method of joining a pipe of a pipe joint, and shows a state in which a spacer is set. The same is a cross-sectional view showing a method of joining a pipe of a pipe joint, showing a state in which an insertion slot is further inserted into a socket and the tip of the insertion slot abuts on the back end surface of the socket. It is sectional drawing of the conventional pipe joint. It is a partially enlarged view of the elastic member used for a pipe joint. The same is a cross-sectional view showing a method of joining a pipe of a pipe joint, and shows a state in which the diameter of the lock ring is expanded by using a mantis shrimp vise. It is the figure which shows the joining method of the pipe of the pipe joint, and shows the state which the diameter of the lock ring was expanded by using the mantis shrimp vise.

Hereinafter, embodiments of the present invention will be described with reference to the drawings.

As a method of piping a water pipe, a method of performing piping inside a shield or adopting a propulsion method is used. As a detachment prevention pipe joint of a ductile iron pipe that can be used for such a shield inner pipe or a propulsion method, for example, the structure of the detachment prevention pipe joint 1 shown in FIG. 1 will be described below.

The insertion port 5 of the other tube 4 is inserted into the receiving port 3 of one tube 2 joined to each other, and the outer periphery of the insertion port 5 at a position separated from the tip of the insertion port 5 in the pipe axis direction 7 An outer peripheral protrusion 6 protruding outward in the pipe radial direction 8 is formed over the entire circumference. The outer peripheral protrusion 6 has a form in which a rising portion (protrusion portion) is directly formed on the outer periphery of the insertion port 5, or a groove is formed on the outer periphery of the insertion opening 5 and another member is fitted into the groove to raise the outer peripheral protrusion portion (protrusion portion). ), Or a groove is formed on the outer periphery of the insertion slot 5 so that the space between the tip of the insertion slot 5 and the groove functions as an outer peripheral protrusion. Further, the present invention is not limited to these forms.

As shown in FIGS. 1 and 2, an annular protrusion 9 protruding inward in the pipe radial direction 8 is formed on the inner circumference of the receiving port 3.

A sealing material pressure contact surface 20 is formed on the inner circumference of the receiving port 3 and between the annular protrusion 9 and the back end surface 19 of the receiving port 3 in the pipe axis direction 7 over the entire circumference. The sealing material pressure contact surface 20 has a tapered portion whose diameter is reduced from the back side of the receiving port 3 toward the annular protrusion 9.

An annular seal member accommodating space 25 is formed over the entire circumference between the sealing material pressure contact surface 20 on the inner circumference of the receiving port 3 and the outer periphery of the insertion port 5. In the seal member accommodating space 25, a seal member 26 that seals between the inner circumference of the receiving port 3 and the outer circumference of the insertion port 5 is inserted.

Further, there is a mounting space 27 between the seal member 26 in the pipe axis direction 7 and the back end surface 19 of the receiving port 3 and between the inner circumference of the receiving port 3 and the outer periphery of the insertion port 5 in the pipe radial direction 8. It is formed all around.

The mounting space 27 is sandwiched between a push ring 29 that presses the seal member 26 against the seal member accommodating space 25 to keep it in a compressed state, and the back end surface 19 of the receiving port 3 and the push ring 29 in the pipe axial direction 7. A plurality of spacers 30 are accommodated.

As shown in FIG. 3, the sealing member 26 has a valve portion 32 having a circular cross section made of soft rubber (an example of an elastic body) and a heel portion 33 having a wedge shape having a cross section made of hard rubber (an example of an elastic body). It is an annular member having and is inserted into the seal member accommodating space 25 with the valve portion 32 at the tip.

As shown in FIG. 4, the push ring 29 is an annular ring having a split structure having a divided portion 40 at one position, whereby the diameter of the push ring 29 can be slightly reduced.

As shown in FIG. 1, the spacer 30 keeps a predetermined distance 31 between the back end surface 19 of the receiving port 3 and the push ring 29 in the pipe axis direction 7, and a metal plate is used, and FIG. As shown by the virtual line of No. 38, they are provided at a plurality of locations at intervals in the pipe circumferential direction 38. The predetermined interval 31 is an interval when the sealing member 26 is compressed to a compression amount required for sealing.

Further, as shown in FIGS. 1 and 2, a lock ring accommodating groove 11 located between the annular protrusion 9 and the opening end portion 10 of the receiving port 3 is formed on the inner circumference of the receiving port 3 over the entire circumference. Has been done. The lock ring accommodating groove 11 accommodates a lock ring 13 that is externally fitted to the insertion port 5 and a pressing member 14 that presses the lock ring 13 inward 17 in the pipe radial direction. The outer peripheral protrusion 6 is located between the annular protrusion 9 and the lock ring 13 in the pipe axis direction 7, and can be engaged with the lock ring 13 from the insertion / removal direction 12 of the insertion port 5.

The lock ring accommodating groove 11 has a bottom surface 21 and a pair of side surfaces 22 and 23 facing each other in the pipe axis direction 7. Of these, one side surface 22 close to the opening end portion 10 is a tapered surface whose diameter is reduced as the distance from the bottom surface 21 to the insertion / removal direction 12 of the insertion port 5.

As shown in FIG. 5, the lock ring 13 is an annular ring having a split structure having a divided portion 15 at one position, whereby the diameter of the lock ring 13 can be slightly expanded or contracted.

As shown in FIGS. 6 to 11, the pressing member 14 is an annular member, and is provided between the outer peripheral surface of the lock ring 13 and the bottom surface 21 of the lock ring accommodating groove 11. Further, the pressing member 14 is a plurality of pressing bodies 43 arranged at predetermined intervals A in the tube circumferential direction 38, and a plurality of spacing holding bodies that maintain a gap between adjacent pressing bodies 43 in the tube circumferential direction 38. It has a plurality of connecting members 45 for connecting the end portion of the pressing body 43 in the tube circumferential direction 38 and the end portion of the spacing holding body 44.

As shown in FIGS. 8 and 9, the pressing body 43 is a flat plate made of a material harder than the space holding body 44, for example, stainless steel (an example made of metal), and has a certain degree of elasticity. Further, the space holding body 44 is a resin plate that is more flexible and flexible than the pressing body 43.

The connecting member 45 is a U-shaped resin member, and is formed between a pair of plates 47 facing each other, a connecting portion 48 for connecting one end edges of the pair of plates 47, and a pair of plates 47. It has a gap 49 and a gap 49.

By inserting the end portion of the pressing body 43 and the end portion of the spacing holding body 44 into the gap 49 of the connecting member 45, the pressing body 43 and the spacing holding body 44 are detachably connected as shown in FIG.

Hereinafter, the operation in the above configuration will be described.

As shown in FIG. 1, in a state where the insertion port 5 is inserted into the receiving port 3 and one tube 2 and the other tube 4 are joined, the pressing member 14 is shown in the solid lines of FIGS. 10 and 11. Each pressing body 43 of the above abuts on the outer peripheral surface of the lock ring 13 and is slightly deformed outward in the pipe radial direction 18 and causes the lock ring 13 to be inward 17 in the pipe radial direction due to the elastic force trying to return to the original shape. Press. Therefore, the lock ring 13 is pressed inward 17 in the pipe radial direction by each pressing body 43 and hugs the outer periphery of the insertion port 5.

In addition, FIG. 10 shows each component in the cross-sectional structure when the pressing member 14 and the lock ring 13 are fitted into the lock ring accommodating groove 11, the insertion port 5 is inserted into the receiving port 3, and the pipes 2 and 4 are joined to each other. It is a figure which shows the arrangement schematically, and does not reflect a concrete shape such as deformation of a pressing body 43. The specific shape such as the deformation of the pressing body 43 is shown in the enlarged view shown in FIG.

As shown in FIG. 11, when each pressing body 43 presses the lock ring 13, both ends 43a of the pressing body 43 in the tube circumferential direction 38 pass through the connecting member 45 to the bottom surface 21 of the lock ring accommodating groove 11. In this state, the pressing body 43 is deformed from a flat shape (see virtual line) to an arc shape (see solid line) slightly bulging outward in the pipe radial direction 18 with both ends 43a as fulcrums. ..

Further, when a detaching force acts on the insertion port 5 due to an earthquake or the like and the insertion opening 5 moves in the removal direction 12 with respect to the receiving port 3, as shown in FIG. 1, the outer peripheral protrusion 6 moves to the receiving port 3. It engages with the lock ring 13 from the back side of the door, whereby it is possible to prevent the insertion port 5 from coming off from the receiving port 3.

At this time, since one side surface 22 of the lock ring accommodating groove 11 is a tapered surface, when the lock ring 13 abuts on one side surface 22 and is further pushed in the removal direction 12, the pipe radial direction inward 17 Since the reaction force of the lock ring 13 acts on the lock ring 13 from one side surface 22, the lock ring 13 more strongly clings to the outer periphery of the insertion slot 5.

The method of joining the pipes 2 and 4 of the pipe joint 1 will be described below.

First, as shown in FIG. 12, the push ring 29 is reduced in diameter and inserted from the opening end portion 10 of the receiving port 3 into the inner part of the receiving port 3 in this state.

Next, as shown in FIG. 8, the end portion of the pressing body 43 and the end portion of the spacing holding body 44 are inserted into the gap 49 of the connecting member 45 to be connected, and the pressing body 43 and the spacing holding body 44 are sequentially connected. It is fitted into the lock ring accommodating groove 11. As a result, as shown in FIG. 6, the pressing member 14 can be easily formed and fitted into the lock ring accommodating groove 11.

After that, an external force is applied to the lock ring 13 to reduce the diameter of the lock ring 13, and the lock ring 13 is fitted into the lock ring accommodating groove 11 from the opening end portion 10 of the receiving port 3 in this reduced diameter state. At this time, the divided portion 15 of the lock ring 13 is directed toward the bottom of the pipe. After that, by releasing the external force, the diameter of the lock ring 13 is restored, and the lock ring 13 is accommodated in the lock ring accommodating groove 11 with the divided portion 15 facing down. As a result, as shown in FIG. 12, the pressing member 14 in the lock ring accommodating groove 11 is provided between the outer peripheral surface of the lock ring 13 and the bottom surface 21 of the lock ring accommodating groove 11.

Next, as shown in FIGS. 13 and 14, a diameter-expanding jig such as a mantis shrimp 51 is hung on the opening end 10 of the receiving port 3 to expand the diameter of the lock ring 13. At this time, the lock is held until the inner peripheral surface of the lock ring 13 is flush with the inner peripheral surface of the receiving port 3 against the pressing force of the pressing member 14 inward 17 in the pipe radial direction. The diameter of the ring 13 is expanded. The mantis shrimp 51 is set at a plurality of positions along the tube circumferential direction 38.

At this time, the lock ring 13 is pressed inward 17 in the pipe radial direction by a plurality of pressing bodies 43 of the pressing member 14, but these pressing bodies 43 are not arranged over the entire circumference of the pressing member 14. , As shown in FIG. 6, are arranged at predetermined intervals A in the tube circumferential direction 38. Therefore, the lock ring 13 is not pressed inward 17 in the radial direction over the entire circumference, but is pressed inward 17 in the radial direction at a plurality of intervals in the peripheral direction 38 of the pipe.

As a result, the mantis shrimp 51 may be set with reference to the portion where the lock ring 13 is pressed by the pressing body 43, and the mantis shrimp vise 51 or the like required for expanding the diameter of the lock ring 13 may be expanded. By reducing the number of jigs, it is possible to reduce the labor and labor required for joining the pipes 2 and 4.

When the diameter of the lock ring 13 is expanded by using the mantis shrimp 51 as described above, the divided portion 15 of the lock ring 13 also expands in the circumferential direction. A stopper 53 for preventing diameter reduction is fitted into the enlarged divided portion 15. As a result, the diameter of the lock ring 13 is prevented from shrinking, and the lock ring 13 is kept in the expanded state.

The diameter reduction prevention stopper 53 is formed of a plate-like body as shown in FIG. 17, and has a wide fitting portion 54 fitted into the divided portion 15 of the lock ring 13 and an external protruding piece 55 integrally. The external projecting piece 55 projects from the position of the lock ring accommodating groove 11 toward the front and the outside of the opening end portion 10 of the receiving port 3 through the gap between the outer periphery of the insertion port 5 and the inner circumference of the receiving port 3. .. Further, a detaching wire 56 is connected to the external protruding piece 55.
As shown in FIGS. 15 and 16, after setting the diameter reduction prevention stopper 53, all the mantis shrimp vise 51 are removed from the opening end portion 10 of the receiving port 3. At this time, the disconnection wire 56 of the diameter reduction prevention stopper 53 is introduced into the other pipe 4 from the receiving side (not shown) opposite to the insertion port 5 of the other pipe 4.

Then, as shown in the virtual line of FIG. 16, the insertion port 5 is inserted into the inside of the receiving port 3 from the opening end portion 10 of the receiving port 3. At this time, since the lock ring 13 is kept in the enlarged diameter state by the diameter reduction prevention stopper 53, the outer peripheral protrusion 6 of the insertion port 5 receives the inside of the lock ring 13 from the opening end portion 10 side of the receiving port 3. It can pass to the back side of the mouth 3.

After that, as shown in FIG. 18, the sealing member 26 is inserted inside the receiving port 3 and deposited between the sealing material pressure contact surface 20 of the receiving port 3 and the outer periphery of the insertion port 5. At this time, the push ring 29 is set between the seal member 26 and the back end surface 19 of the receiving port 3.

Next, as shown in FIG. 19, the push ring 29 presses the seal member 26 by widening the space between the push ring 29 and the back end surface 19 of the receiving port 3 by using a plurality of expansion jigs 60. When pressed, the seal member 26 is pushed into the seal member accommodating space 25 and kept in a compressed state.

The expansion jig 60 includes a hydraulic piston cylinder device (not shown) and a pair of claws 61 and 62. When the piston cylinder device is operated, the other claw 61 is subjected to the operation of the piston cylinder device. It has a structure that allows the claws 62 to move and the distance between both claws 61 and 62 to be expanded or contracted.

One claw 61 is engaged with the back end surface 19 of the receiving port 3, the other claw 62 is engaged with the push ring 29, the piston cylinder device is operated, and the other claw 62 is moved with respect to one claw 61 to both of them. By widening the distance between the claws 61 and 62, the push ring 29 presses the seal member 26 from the back of the receiving port 3 toward the opening end portion 10.

The expansion jigs 60 are set at a plurality of locations in the pipe circumferential direction 38, and the push ring 29 is pressed by using the plurality of expansion jigs 60 as described above.

With the expansion jig 60 set as described above, as shown in FIG. 20, the spacer 30 is fitted between the push ring 29 and the back end surface 19 of the receiving port 3. In this way, the plurality of spacers 30 are set at places where the expansion jig 60 is not set at equal intervals.

Next, the expansion jig 60 is removed, and the insertion slot 5 is inserted into the socket 3 until the tip of the insertion slot 5 comes into contact with the back end surface 19 of the socket 3 as shown in FIG. After that, as shown by the virtual line of FIG. 15 and the virtual line of FIG. 16, the detaching wire 56 is pulled in the other tube 4, and the diameter reduction prevention stopper 53 is removed from the divided portion 15 of the lock ring 13. As a result, as shown in FIGS. 1, 10, and 11, the lock ring 13 is pressed inward 17 in the pipe radial direction by the pressing body 43 of the pressing member 14, so that the elastic force of the lock ring 13 and the pressing body 43 are used. The diameter is reduced by the pressing force of, and it hugs the outer circumference of the insertion port 5 over the entire circumference. This completes the joining work of the pipes 2 and 4.

In the first embodiment, the pressing member 14 is provided between the outer peripheral surface of the lock ring 13 and the bottom surface 21 of the lock ring accommodating groove 11, but the pressing member 14 is not provided and is locked. When the ring 13 is fitted into the lock ring accommodating groove 11 and the pipes 2 and 4 are joined, the lower part of the lock ring 13 is mainly inserted while the upper part of the lock ring 13 is supported by the pipe top of the insertion port 5. It may not be able to sufficiently hug the outer periphery of the opening 5, and the inner peripheral surface of the lower portion of the lock ring 13 may be slightly separated from the outer peripheral surface of the insertion port 5.
In order to deal with such a problem, in the first embodiment, the annular pressing member 14 is provided between the outer peripheral surface of the lock ring 13 and the bottom surface 21 of the lock ring accommodating groove 11. The pressing member 14 is not limited to an annular shape, and a semicircular annular pressing member 14 having only a lower region may be provided between the outer peripheral surface of the lock ring 13 and the bottom surface 21 of the lock ring accommodating groove 11.

In each of the above embodiments, a stainless steel flat plate is used for the pressing body 43, but a metal plate having elasticity other than stainless steel may be used.

In each of the above embodiments, as shown in FIG. 5, the lock ring 13 is a ring having a split structure, but it may be a ring having a structure that can be divided into a plurality of rings.

In each of the above embodiments, as shown in FIG. 9, the space holding body 44 and the connecting member 45 are detachably separated, but the space holding body 44 and the connecting member 45 are integrally molded with resin. You may. Further, the pressing body 43 and the connecting member 45 may be integrally molded, or the pressing body 43, the interval holding body 44, and the connecting member 45 may be integrally molded.

In each of the above embodiments, as shown in FIG. 8, the pressing body 43 has a plate shape, but the shape is not limited to this shape and may be a pillar shape. Further, the shape may have a concave portion or a convex portion in a part thereof. The spacing holding body 44 is not limited to the plate shape, and may be a pillar shape, as in the pressing body 43. Further, the shape may have a concave portion or a convex portion in a part thereof.

In each of the above embodiments, as shown in FIGS. 18 to 20, the insertion port 5 is inserted into the inside of the reception port 3 from the opening end portion 10 of the reception port 3, and the outer peripheral protrusion 6 is inside the lock ring 13. The seal member 26, the push ring 29, and the spacer 30 are set in the receiving port 3 in a state where the seal member 26, the push ring 29, and the spacer 30 have passed from the opening end portion 10 side of the receiving port 3 to the inner side of the receiving port 3. For example, the insertion port 5 is inserted from the opening end portion 10 of the receiving port 3 into the inside of the receiving port 3, and the outer peripheral protrusion 6 is inside the lock ring 13 or in front of the lock ring 13. The seal member 26, the push ring 29, and the spacer 30 are set in the receiving port 3 while being located on the opening end portion 10 side of the opening portion 10, and then the tip of the insertion opening 5 hits the back end surface 19 of the receiving port 3. The pipes 2 and 4 may be joined to each other by inserting the insertion port 5 into the receiving port 3 until they come into contact with each other and removing the diameter reduction prevention stopper 53 from the divided portion 15 of the lock ring 13.

1 Pipe fitting 2 One pipe 3 Receptacle 4 The other pipe 5 Insertion 6 Outer protrusion 11 Lock ring accommodating groove 12 Detachment direction 13 Lock ring 14 Pressing member 15 Divided part 17 Pipe radial inward 18 Pipe radial outside Orientation 21 Bottom surface of lock ring accommodating groove 38 Pipe circumferential direction 43 Pressing body 44 Spacing body 53 Stopper for preventing diameter reduction

Claims (5)

The insertion port of the other tube is inserted into the socket of one tube,
A lock ring accommodating groove is formed on the inner circumference of the receiving port,
The lock ring is housed in the lock ring housing groove and fitted outside the insertion slot.
An outer peripheral protrusion is formed on the outer periphery of the insertion port so as to project outward in the radial direction of the pipe.
A pipe joint having a detachment prevention function that prevents the insertion port from being removed from the receiving port by engaging the outer peripheral protrusion with the lock ring from the insertion / removal direction of the insertion port.
A pressing member for pressing the lock ring inward in the radial direction is provided between the outer peripheral surface of the lock ring and the bottom surface of the lock ring accommodating groove.
The pressing member has a plurality of pressing bodies arranged at predetermined intervals in the tube circumferential direction, and a plurality of spacing holding bodies that maintain the spacing between adjacent pressing bodies in the tube circumferential direction .
The end of the pressing body in the circumferential direction of the pipe and the end of the spacing holding body are detachably connected by a connecting member.
A pipe joint characterized in that the pressing body abuts on the outer peripheral surface of the lock ring and presses the lock ring inward in the radial direction of the pipe. When the pressing body presses the lock ring, both ends of the pressing body in the tube circumferential direction are pressed against the bottom surface of the lock ring accommodating groove via the connecting member, and in this state, the pressing body has the tube with both ends as fulcrums. The pipe joint according to claim 1, wherein the pipe joint is deformed into an arc shape that bulges outward in the radial direction . The pipe joint according to claim 1 or 2, wherein the lock ring is a ring having a 10-piece structure having a divided portion at one place. The pressing body is a metal plate,
The pipe joint according to any one of claims 1 to 3, wherein the space holding body is a plate made of a flexible resin. The method for joining a pipe of a pipe joint according to claim 3 above.
A plurality of pressing bodies and spacing holders are fitted into the lock ring accommodating groove of the receiving port to form a pressing member.
Fit the lock ring into the lock ring storage groove and
Enlarge the diameter of the lock ring and put a diameter reduction prevention stopper in the divided part of the lock ring to keep the lock ring in the expanded state.
The insertion port is inserted into the lock ring and the receiving port, and the outer peripheral protrusion is passed through the lock ring from the opening end side of the receiving port to the back side of the receiving port.
A pipe joining method characterized in that the diameter reduction prevention stopper is removed from the divided portion of the lock ring to reduce the diameter of the lock ring.

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