JPH11325347A - Pipe joint - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a pipe joint to facilitate operation of inserting fluid pipes into a pipe joint body and to prevent leakage, when the fluid pipes are joined. SOLUTION: When fluid pipes 2 are inserted into a pipe joint body 3 in which packings 6 are installed, a minimum internal diameter of the packaging 6 is set larger than a outer diameter of the fluid pipes 2 to enable smooth insertion of the fluid pipes 2 without occurrence of insert resistance. The packings 6 are disposed in a spreading diameter portions 3a. After the fluid pipes 2 are inserted into the pipe joint body 3 engaged with pushing rings 4 by engaging apparatuses 3b, the packings 6 are pressed into the spreading diameter portions 3a by the pushing rings 4. The packings 6 are abutted on walls to be fixedly positioned. By further pressing the packings 6 to be compressed and thereby to make the spread diameter portions 3a stop water, and then seal portions are press-contacted with peripheral surfaces of the fluid pipes 2, resulting in preventing occurrence of leakage.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

TECHNICAL FIELD The present invention relates to a water pipe, a gas pipe,
The present invention relates to a pipe joint for joining a fluid pipe such as a pipe for a plant.

[0002]

2. Description of the Related Art Conventionally, there has been known a pipe joint whose joining is completed only by inserting a fluid pipe as shown in FIG. 8, and this pipe joint has an enlarged diameter portion C for accommodating a packing B on an inner peripheral surface. It comprises a joint body A provided and a packing B for joining the fluid pipe P and the joint body A in a watertight manner.

[0003] The fluid pipe P is inserted into the joint body A in which the packing B is installed at the enlarged diameter portion C while compressing the packing B. The packing B is formed between the outer peripheral surface of the fluid pipe P and the inner periphery of the enlarged diameter portion C. The seals are tightly sealed on both sides with the restoring force compressed between them.

[0004] As another conventional example, there is known a pipe joint which pushes a packing B shown in Fig. 9 into a joint body A with a pressing wheel F to stop water, and this pipe joint has a packing B on an inner peripheral surface of an end portion.
Is provided, and a tapered surface E whose diameter is sharply reduced toward the back is formed on the inner side of the expanded portion C,
A joint body A provided with a flange D on the outer peripheral surface;
An annular packing B having a substantially trapezoidal cross-sectional shape, a pressing wheel F provided with a flange I that matches the flange D, and a pressing portion G abutting the packing B protruding from the joint body A side;
Bolt / nut H for joining flange D and flange I
It is composed of

[0005] Fluid pipe P with press ring F and packing B fitted outside
Is inserted into the joint body A, and the flange D and the flange I are fastened with the bolts and nuts H, the pressing ring F is drawn to the joint body A, the packing B is pressed by the pressing portion G, and the enlarged diameter portion C
Stuffed inside. The packing B is compressed by the inner peripheral surface of the tapered surface E and the inner peripheral surface of the enlarged diameter portion C and the outer peripheral surface of the fluid pipe P to be in close contact with each other to stop water.

[0006]

In the former pipe joint of the prior art, since the fluid pipe P is inserted into the joint body A while compressing the packing B fitted in the enlarged diameter portion C, the insertion resistance is large. Since the joining operation has to be performed using a dedicated device for insertion, it seems to be a simple operation of merely inserting the fluid pipe into the joint body, but the workability is not so good. If the fluid pipe P is inserted in a wrong direction, the packing B may be rolled up or come off the enlarged diameter portion C, and the state of the packing after joining cannot be confirmed. There was a leak.

[0007] In the latter pipe joint, a push ring F and a packing B are externally fitted to a fluid pipe P and then inserted into a joint body A.
Since the pressing ring F and the packing B have to be moved, the workability is poor, and if the pressing ring F is not evenly tightened to the joint main body A, the pressing ring F tilts and the packing may be cut off to leak water.

[0008] The problem to be solved by the present invention is to solve the above-mentioned problem, and at the time of joining the fluid pipes, the work of inserting the fluid pipe into the joint body is easy and there is no fear of water leakage. It is in providing a pipe joint.

[0009]

In order to solve the above-mentioned problems, a pipe joint according to the present invention is provided with an enlarged-diameter portion for accommodating a packing having an opening at a front end and a wall formed at a center side, and is provided with a packing. A fitting body into which the fluid pipe is inserted, a push ring for pushing the packing into the enlarged diameter portion, and an engaging device for pulling and engaging the push ring with the joint body, wherein the packing is a fluid pipe. When the gasket is inserted, that is, when the gasket is not pressed, the minimum inner diameter of the gasket is set larger than the outer diameter of the fluid pipe. It is characterized in that a seal portion is provided in contact with the outer peripheral surface of the pipe.

A seal surface formed near the outer peripheral surface and abutting against the wall to determine the position of the packing; a lip portion provided closer to the inner peripheral surface and protruding from the abutment surface; It is preferable that the recess is formed between the abutment surface and the lip.

The enlarged diameter portion is provided with an inner tapered surface which is reduced in diameter from the end of the joint body toward the center, and an outer tapered surface which matches the inner tapered surface is provided on an outer peripheral surface of the packing. Is preferred.

It is preferable that the inner peripheral side of the end face on the pressing wheel side of the packing is convex.

According to the pipe joint of the present invention, when the fluid pipe is inserted into the joint body to which the packing is attached, since the minimum inner diameter of the packing is set larger than the outer diameter of the fluid pipe, insertion resistance is generated. It can be inserted smoothly without doing. In addition, after the packing is arranged in the enlarged diameter portion and the fluid pipe is inserted into the joint body in which the pressing ring is engaged by the engagement device, the packing is pushed into the enlarged diameter portion by the pressing ring, and the position abuts on the wall and is fixed. When further pushed in, it is compressed to stop the water at the enlarged diameter portion, and the seal portion is pressed against the outer peripheral surface of the fluid pipe, so that there is no fear of causing water leakage.

[0014]

Embodiments of the present invention will be described below with reference to the drawings.

1 to 4 show a first embodiment in which fluid pipes 2 and 2 made of polyethylene are joined by using a pipe joint 1 of the present invention. Reference numeral 3 denotes a joint body made of ductile cast iron.
A push ring fastened to the joint body 3, a lock ring 5 arranged on the inner peripheral surface of the push ring 4, and a fluid ring 2 connected to the joint body 3
, A retainer 7 for pressing the packing 6, and 8 an in-core mounted on the inner circumference of the end of the fluid pipe 2.

At the center of the inner surface of the joint body 3, there is provided a stopper 3d projecting toward the center of the pipe, and at both ends thereof, an enlarged diameter portion 3a for accommodating the packing 6 is formed. A locking device 3c is provided at an end of the enlarged-diameter portion 3a to prevent the retainer 7 from abutting and preventing its movement.

The joint body 3 may be made of not only ductile cast iron but also stainless steel, or may be made of synthetic resin.

The enlarged diameter portion 3a is composed of a first enlarged diameter portion 3e for accommodating a main body of the packing 6, which will be described later, and a second enlarged diameter portion 3f for accommodating a lip portion. Diameter part 3
The inner peripheral surface of e is formed with an inner tapered surface 3g whose diameter is reduced from the end surface of the joint body 3 toward the center, and a wall 3h is provided on the inner side of the inner tapered surface 3g toward the center of the pipe. ing.

The inner peripheral surface of the second enlarged-diameter portion 3f is formed with a housing tapered surface 3i whose diameter is reduced from the end surface of the joint body 3 toward the center, and continues from the wall 3h to the housing tapered surface 3i. Is a tapered wall 3j whose diameter is rapidly reduced toward the center.
Is provided.

A flange 4b (engaging device) of the pressing wheel 4 is attached to a flange 3b provided on an outer peripheral surface of the joint body 3 by a plurality of T-head bolts 9 (engaging device) and nuts 10 (engaging device). The lock ring 5 is tightened by the inner tapered surface 4a of the pressing wheel 4.

The lock ring 5 has a split shape made of a synthetic resin harder than the fluid pipe 2, for example, an acetal resin or a metal body such as stainless steel. The outer peripheral surface is formed with an outer tapered surface 5a having substantially the same inclination as the inner tapered surface 4a of the pressing ring 4, and its maximum outer diameter is set to be larger than the maximum inner diameter of the inner tapered surface. A plurality of blades 5b facing in the circumferential direction are formed on the inner peripheral surface.

The packing 6 has an outer tapered surface 6a having substantially the same angle as the inclination angle of the inner tapered surface 3g formed on the outer peripheral surface. The contact surface 6b perpendicular to the outer peripheral surface is on the outer peripheral surface side, the tongue-shaped lip 6c protruding from the contact surface 6b is on the inner peripheral surface side, and between the contact surface 6b and the lip portion 6c. A concave portion 6d is formed, and a convex portion 6e protruding toward the pressing wheel 4 is formed on the inner peripheral surface side at the end portion on the pressing wheel 4 side, and the minimum inner diameter is set to be larger than the outer diameter of the fluid pipe 2. .

The outer diameter of the in-core 8 is substantially equal to the inner diameter of the fluid pipe 2, and a flange 8a protruding in the outer diameter direction is formed at one end.

Using the pipe joint 1 of the above embodiment, a fluid pipe 2
First, the incore 8 is inserted until the flange 8a comes into contact with the end of the fluid pipe 2 to be joined.

Next, a T-head bolt 9 is inserted into the flange 3b and the flange 4b, and the nut 10 is temporarily tightened. The pressing ring 4 in which the lock ring 5 and the retainer 7 are mounted is attached to the expanded portion 3a by the packing 6. Temporarily fix to the inserted joint body 3.

Next, the fluid pipe 2 in which the in-core 8 is mounted is inserted from the end of the press ring 4 temporarily fixed to the joint body 3 until it comes into contact with the stopper 3d, and the nut 10 temporarily tightened is connected to the flange 3b. The flanges 4b are evenly tightened until they come into contact with each other to complete the joining.

FIG. 5A shows a state in which the fluid pipe 2 is inserted into the place where the press wheel 4 is temporarily fixed to the joint body 3. Since the inner diameter of the lock ring 5 and the inner diameter of the packing 6 are set to be larger than the outer diameter of the fluid pipe 2, the fluid pipe 2 can be smoothly inserted into the joint body 3 without insertion resistance.

FIG. 5B shows that the temporarily tightened nut 10 is tightened, the retainer 7 abuts the locking portion 3c of the joint body 3, the lock ring is reduced in diameter, and the joint of the pipe joint is reduced. This shows a state where the processing has been completed. Packing 6 is expanded part 3a
When pressed, the abutting surface 6b abuts on the wall 3h to fix the position, and when further pressed, is compressed by the inner tapered surface 3g, so that the outer tapered surface 6a of the packing 6 comes into close contact with the inner tapered surface 3g, Further, the contact surface 6b is pressed against the wall 3h. Since the joint between the tapered wall 3j and the housing tapered surface 3i abuts on the lip 6c, the concave portion 6d is deformed in the expanding direction, and the outer peripheral surface is controlled by the inner tapered surface 3g and the wall 3h. Is pressed in the direction of the center of the pipe and is in contact with the outer peripheral surface of the fluid pipe 2.

In the present embodiment, since the minimum inner diameter of the packing 6 is set to be larger than the outer diameter of the fluid pipe 2, the fluid pipe can be easily inserted. Also, the contact surface 3
Since the h and the concave portion 3j are provided, when the packing 6 is pushed into the enlarged diameter portion 3a, the lip portion 6c is deformed to abut against the outer peripheral surface of the fluid pipe 2, so that an initial pressure contact force can be obtained. There is no worry about water leakage.

Further, since the convex portion 6e protruding toward the pressing wheel 4 is formed on the inner peripheral surface side of the packing, when the packing is pressed, it is deformed in the outer peripheral direction and protrudes outside the enlarged diameter portion to retain the retainer 7. And the locking portion 3c, the shortage of the predetermined amount of movement of the flange can be prevented.

FIGS. 6 and 7 show a second embodiment of the present invention, in which a joint body 3, a press ring 4, a lock ring 5, and a retainer 7 are shown.
Are substantially the same as those in the first embodiment, except that a lip portion 6f is provided on the joint body 3 side of the packing 6 with the contact surface 6b as a base and extending obliquely forward in the inner circumferential direction. I have.

The connection of the fluid pipe 2 using the pipe joint 1 of the second embodiment is performed in the same manner as in the first embodiment, and when the packing 6 is pushed into the enlarged diameter portion 3a, the connection is made. The contact surface 6b abuts against the wall 3h to fix the position. When the contact surface 6b is further pushed in, the inner taper surface 3g compresses the outer taper surface 6a so as to be in close contact with the inner taper surface 3g. The lip 6f abuts against the tapered wall 3j and deforms so as to stand up, and the tip of the lip 6f is pressed against the outer peripheral surface of the fluid pipe 2 to stop water.

In the embodiment, the engagement device is a flange provided on the joint body and the pressing ring, a T-head bolt, and a nut.
It may be a screw portion for screwing a push ring to the joint body.

Further, in the embodiment, the lock ring for preventing the pull-out is provided on the pressing wheel, but a normal pressing wheel without the pull-out preventing may be used.

[0035]

According to the present invention, since the minimum inner diameter of the packing is set to be larger than the outer diameter of the fluid pipe, when the fluid pipe is inserted, no insertion resistance occurs and the insertion operation can be performed smoothly. And workability is improved. Further, when the packing is pushed into the enlarged-diameter portion by the pressing ring, a seal portion is provided which abuts against the inner wall of the enlarged-diameter portion, and is deformed so as to be further pushed into contact with the outer peripheral surface of the fluid pipe. Since the packing, which does not come into contact with the outer peripheral surface of the fluid pipe, is easy to insert, the packing can be pushed into the large-diameter portion to ensure watertightness in contact with the outer peripheral surface of the fluid pipe, which may cause water leakage. Absent.

According to the second aspect of the present invention, the packing has an abutting surface that abuts against the inner wall of the enlarged diameter portion, a lip protruding from the abutting surface, and a gap between the abutting surface and the lip. Since the recessed portion is provided, the concave portion is deformed to open when the packing is pushed into the enlarged diameter portion, and the contact surface is fixed here, so the lip portion is The outer peripheral surface is pressed against the outer peripheral surface of the fluid pipe, and the initial pressure contact is ensured, so that the self-sealing effect works effectively and does not cause water leakage.

According to the third aspect of the present invention, since the outer peripheral surface of the packing is provided with the outer tapered surface that matches the inner tapered surface of the enlarged diameter portion, the packing can be smoothly mounted on the enlarged diameter portion. When the packing is pushed into the enlarged-diameter portion, the wedge action ensures the press-contact to the inner tapered surface and does not cause water leakage.

According to the fourth aspect of the present invention, since the protrusion is formed on the inner peripheral surface side of the packing, the packing is not deformed in the outer peripheral direction and does not protrude outside the enlarged diameter portion.
A predetermined amount of movement of the flange can be secured, and water leakage due to insufficient pressing of the packing can be prevented.

[0039]

[Brief description of the drawings]

FIG. 1 is a sectional view showing a first embodiment of the present invention.

FIG. 2 is also a side view.

FIG. 3 is a partially enlarged sectional view showing the joint body.

FIG. 4 is an enlarged sectional view showing a packing.

FIG. 5A is a partial cross-sectional view when a fluid pipe is inserted,
(B) is a partial cross-sectional view at the end of joining.

FIGS. 6A and 6B show a second embodiment of the present invention, wherein FIG. 6A is a partial sectional view when a fluid pipe is inserted, and FIG.

FIG. 7 is an enlarged sectional view showing the packing.

FIG. 8 is a partially cutaway front view showing a conventional example.

FIG. 9 is a partially cutaway front view showing another conventional example.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Pipe joint 2 Fluid pipe 3 Joint main body 3a Large diameter part 3b Flange (engaging device) 3c Lock part 3d Stopper 3e First large diameter part 3f Second large diameter part 3g Inner tapered surface 3h Wall 3i Housing taper surface 3j Taper Wall 4 Pressing wheel 4a Inner taper surface 4b Flange (engaging device) 5 Lock ring 5a Outer taper surface 5b Blade 6 Packing 6a Outer taper surface 6b Contact surface 6c Lip 6d Concave 6e Convex 6f Lip 7 Retainer 8 Incore 8a Collar 9 T-head bolt (engaging device) 10 Nut (engaging device)

Claims (4)

[Claims] An enlarged diameter portion is provided for accommodating a packing having an opening at a distal end and a wall formed at a center side, and a joint body into which a fluid pipe is inserted via the packing, and the packing is pushed into the enlarged diameter portion. A push ring, a pipe joint comprising an engagement device for pulling the push ring to a joint body to engage with the joint body, wherein the packing has a minimum inner diameter of the packing when the fluid pipe is inserted, that is, when the packing is not pressed. A pipe which is set to be larger than the outer diameter and is provided with a seal portion which is deformed by coming into contact with the wall when being pushed into the enlarged diameter portion by a pressing wheel, and which is in contact with the outer peripheral surface of the fluid pipe. Fittings. 2. A contact surface formed near an outer peripheral surface of the seal portion, the contact portion being in contact with the wall to determine a position of a packing;
2. The tube according to claim 1, comprising a lip protruding from the contact surface provided near the inner peripheral surface, and a concave portion formed in a concave shape between the contact surface and the lip. Fittings. 3. An inner tapered surface is provided at the enlarged diameter portion, the inner tapered surface decreasing in diameter from an end of the joint body toward the center, and an outer tapered surface matching the inner tapered surface is provided on an outer peripheral surface of the packing. The pipe joint according to claim 1, wherein the pipe joint is provided. 4. The pipe joint according to claim 1, wherein the inner peripheral side of the end face on the pressing wheel side of the packing is convex.