JPH07167360A - Temporary tightening structure of flexible expansion pipe joint - Google Patents

Abstract

PURPOSE:To provide pipe joint temporary tightening structure enabling the construction of a pipe joint only by inserting a connecting pipe with no possibility of the inner diameter of a rubber packing becoming smaller than the outline of the connecting pipe even in the temporarily tightened state. CONSTITUTION:An unthreaded connecting pipe is inserted into a joint body 2 or a pipe with a tapered faucet part, and an annular rubber packing 6 is interposed in the fittingly inserted state and tightened to the joint body 2 or pipe by a bolt 11 and a nut 12 which are the tightening means of a pressure ring 7. In such a flexible expansion joint, foam styrene 13 for securing specified interference is interposed between the pressure ring 7 and the protruding part of the joint body 2 or pipe, and the pressure ring 7, rubber packing 6 and joint body 2 or pipe are integrally and temporarily tightened.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a pipe joint having elasticity and flexibility, in which a rubber packing is prevented from being contracted in diameter before a construction work, and a temporary tightening structure for the expansion and contraction flexible pipe joint is provided. It is about.

[0002]

2. Description of the Related Art A pipe joint shown in a partial vertical sectional view of FIG. 11 is well known as a pipe joint of this type having excellent elasticity and flexibility. In this conventional technique, the inner diameter of the tapered receiving portion 3 is set to be larger than the outer diameter of the joining pipe 1, and the central portion in the axial direction swells like a drum to form a wide cavity 4 inside. And the insertion port 5 of the joint pipe 1 is inserted into the receiving port 3.

A rubber packing 6 for sealing is provided between the outer peripheral surface of the joint body 2 and the receiving portion 3 of the joint body 2.
Is inserted and pushed into the joint body 2 from behind by the push ring 7. This pushing is performed by inserting the tightening bolt 11 into the bolt hole 10 of the projecting portion 8 formed on the outer periphery of the end surface of the joint body 2 and the bolt hole 9 of the push ring 7 corresponding to the bolt hole 10 and tightening with the nut 12. By doing.

As a result, the outer peripheral wedge surface and the inner peripheral wedge surface of the rubber packing 6 are pressed between the tapered receiving portion 3 of the joint body 2 and the outer peripheral surface of the joint pipe 1, and the joint pipe 1 and the joint. It is held concentrically with the main body 2 and seals the leakage of fluid from the connection site.

In this state, the pipe end of the joint pipe 1 is
It can move freely in the cavity 4 of the joint body 2 without interfering with the inner wall of the joint body 2, can bend with respect to the axis of the joint body 2, and has flexibility. There is.

[0006]

The joint body 2, the rubber packing 6, and the push ring 7 are temporarily tightened by tightening bolts 11 and nuts 12 to prevent them from being lost on the way. Shipped from the factory. The workability of such a pipe joint in the temporarily tightened state is extremely convenient if the construction work can be performed without disassembling. For that purpose, it is necessary to be able to insert the joining pipe 1 from the outside into the temporarily fastened pipe joint as it is.

In order to satisfy such a requirement, it is necessary to make the inner diameter of the rubber packing 6 of the pipe joint in the temporarily tightened state larger than the outer dimension of the joining pipe 1. This is because if the inner diameter of the rubber packing 6 is smaller than the outer dimension of the joint pipe 1, the rubber pipe 6 will not be inserted later.
This is because it is hindered by and cannot be done.

However, in the prior art, even if the inner diameter of the rubber packing 6 is set to be larger than the outer diameter of the joint pipe 1, the inner diameter of the rubber packing 6 is larger than that of the joint pipe 1 immediately before construction. It was getting smaller.

That is, in the temporarily tightened state, there is nothing for fixing the movement of the push ring 7, so that, for example, the push ring 7 is placed downward until the pipe joint is shipped from the factory and installed on site. When the whole is placed, the push wheel 7 may move forward in the direction in which the rubber packing 6 is pressed and biased.

Therefore, when the push wheel 7 moves forward,
The rubber packing 6 was pressed, and the diameter of the rubber packing 6 was reduced by the action of the tapered receiving portion 3. In other words, it becomes the same as the state where the rubber packing 6 is fully tightened,
Due to the diameter-reducing operation, the inner diameter of the rubber packing 6 is changed to the joint pipe 1.
It was smaller than the external dimensions of.

Therefore, in the prior art, the tightening bolts 11 and nuts 12 of the pipe joint shipped in the temporarily tightened state are removed at the construction site, the whole is disassembled once, and the rubber packing 6 is taken out. The reduced diameter of is corrected to the original inner diameter. After that, the complicated work of reassembling and constructing the pipe joint was performed.

[0012]

DISCLOSURE OF THE INVENTION The present invention has been made by improving and removing the conventional problem in view of the above-mentioned problems. The inner diameter of the rubber packing is smaller than the outer shape of the joining pipe even in the temporarily tightened state. There is no need to provide a temporary fitting structure for a pipe joint, which allows the pipe joint to be constructed simply by inserting the joint pipe.

The means adopted by the present invention in order to solve the above problems is to insert a threadless joint pipe into a pipe or a joint body having a tapered receiving portion, and to form an annular rubber packing. An expansion and contraction flexible pipe joint that is inserted and fitted to tighten the pipe or joint body with bolts and nuts that are the tightening means of the push ring, and has a predetermined tightening margin between the protruding portion of the pipe or joint body and the push ring. A temporary tightening structure for an expansion and contraction flexible pipe joint, characterized in that a push ring, a rubber packing, and a pipe or joint body are temporarily fastened integrally by interposing a styrofoam.

[0014]

In the present invention, as shown in the embodiment of FIG. 1, when pressure is applied with a certain force or more, a remarkable volume change occurs and the volume is reduced, and deformation occurs unless a force greater than a certain amount is applied. The pipe joint is temporarily tightened using the difficult polystyrene foam 13. The Styrofoam 13 is arranged between the protruding portion 8 of the joint body 2 and the push ring 7, and serves as a spacer. Therefore, in a normal state where a force of a certain amount or more does not act, it is possible to secure a gap corresponding to the thickness of the expanded polystyrene 13 between the push ring 7 and the protruding portion 8 of the joint body 2.

Therefore, the push ring 7 does not press and urge the rubber packing 6, and the inner diameter of the rubber packing 6 is equal to that of the joining pipe 1.
It will never be smaller than the outline. Therefore, as shown in FIG. 2, it is possible to insert the tip of the joining pipe 1 from the outside into the cavity 4 of the joint body 2 by inserting the push ring 7 and the rubber packing 6 from the outside in the state of being temporarily tightened. is there.

After the joint pipe 1 is inserted and fitted, as shown in FIG. 3, the fastening bolts 11 and the nuts 12 are tightened, and the push ring 7 is moved forward to compress and reduce the diameter of the rubber packing 6. Is strongly adhered to the joint pipe 1 and sealed. of course,
Even between the tapered surface of the rubber packing 6 and the receiving portion 3 of the joint body 2, the rubber packing 6 is pressure-bonded to ensure the sealing property.

When tightening the fastening bolt 11 and the nut 12, the Styrofoam 13 is compressed and contracted and deformed,
It causes a remarkable volume change. And the thickness becomes extremely small as shown in FIG. It should be noted that this styrofoam 13 does not generate an elastic repulsive force unlike rubber or the like even if the volume changes, and does not hinder the operation of tightening the rubber packing 6 by the forward movement of the push wheel 7.

[0018]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The structure of the present invention will be described below with reference to the embodiments shown in the drawings. The same reference numerals as in the conventional case are the same members. 1 to 4 relate to a first embodiment of the present invention. FIG. 1 is a partial vertical cross-sectional view showing a temporarily tightened state of a pipe joint, and FIG. 2 shows a joint pipe 1 in the temporarily tightened pipe joint. FIG. 3 is a partial vertical cross-sectional view showing a state where the pipe fitting is inserted, FIG. 3 is a partial vertical cross-sectional view showing a state where the pipe joint is fully tightened, and FIG.

In the first embodiment, the expanded polystyrene 13 shown in FIG. 4 is used. The styrofoam 13 has a predetermined thickness, the outer peripheral surface thereof has a quadrangular prism shape, and a through hole 14 for inserting the rubber packing 6 is provided in the central portion, and further, a portion corresponding to the square portion of the through hole 14, A recess 15 for inserting the tightening bolt 11 is continuously formed.

With respect to the thickness of the styrofoam 13, the joint body 2, the push ring 7, and the rubber packing 6 are fastened to each other by tightening bolts 11 and nuts 12 so that the styrofoam 13 is slightly compressed in the temporarily tightened state shown in FIG. So that the push ring 7 does not move forward over the rubber packing 6 when
Its dimensions are set. Therefore, in this temporarily tightened state, the rubber packing 6 does not perform the diameter reducing operation along the tapered receiving portion 3. Therefore, the inner diameter of the rubber packing 6 remains larger than the outer diameter of the joining pipe 1.

In this embodiment, the pipe joint is shipped from the factory in the temporarily tightened state shown in FIG. At the construction site of the pipe joint, as shown in FIG. 2, it is sufficient to insert the pipe end of the joint pipe 1 from the outside of the pipe joint in the temporarily tightened state. This can be realized because the expanded polystyrene 13 prevents the rubber packing 6 from reducing its diameter and secures its inner diameter larger than the outer diameter of the joining pipe 1, as described above. Thus, since it is not necessary to remove the tightening bolt 11 and the nut 12, these small members are not lost.

After that, as shown in FIG. 3, the tightening bolt 11 and the nut 12 with the styrofoam 13 still mounted.
Conclude By this fastening, the Styrofoam 13 undergoes a remarkable volume change and is contracted and deformed in the direction in which the thickness becomes smaller. Therefore, the rubber packing 6 moves forward in response to the forward movement of the push wheel 7, and the rubber packing 6 reduces its diameter due to the action with the tapered receiving portion 3 of the joint body 2 and press-contacts the outer peripheral surface of the joint pipe 1. Then, the original sealing action is performed.

Therefore, the contraction deformation of the polystyrene foam 13 due to the remarkable volume change does not hinder the tightening operation of the pipe joint. When an elastic body such as rubber is interposed as a spacer instead of the Styrofoam 13, the repulsive elastic force increases sharply with the compression, and this impedes the tightening operation of the rubber packing 6, so that it cannot be put to practical use. Is.

In the first embodiment, since the styrofoam 13 is continuous in the entire circumferential direction, soil, stones, or the like will be present between the push ring 7 and the projecting portion 8 of the joint body 2 during construction. It does not invade and does not interfere with tightening work. Further, after the construction, the screw portion of the tightening bolt 11 between the push ring 7 and the protruding portion 8 does not come into contact with the soil,
The tightening bolt 11 will not be corroded electrically or chemically.

FIG. 5 shows expanded polystyrene 16 according to the second embodiment of the present invention. This embodiment is applied to a pipe joint in which two sets of tightening bolts 11 and nuts 12 are used for fastening. That is, the present invention is applied to a pipe joint in which the push ring 7 and the projecting portion 8 of the joint body 2 are fastened using two sets of tightening bolts 11 and nuts 12. Other configurations and operational effects are the same as in the case of the first embodiment.

Further, FIG. 6 relates to a third embodiment of the present invention. In this embodiment, each of the tightening bolts 11 in the first embodiment is provided with a single Styrofoam 17. Styrofoam 1
A U-shaped groove 7 is formed in the tightening bolt 11 between the push ring 7 and the protrusion 8 of the joint body 2 so that the tightening bolt 7 can be mounted later. Other configurations and basically the operational effects are the same as those in the first embodiment.
This is the same as the case of the above embodiment.

Furthermore, FIGS. 9 and 10 show a fourth embodiment of the present invention.
2 shows a polystyrene foam 21 according to the example of FIG.
In this embodiment, a push-fitting wheel 7, which is externally fitted and attached to each of the joint pipes 1 and 1, is attached to both ends of the joint body 2 with a single tightening bolt 11. The technology is applied. Styrofoam 21
Has a ring shape, and is mounted between the protruding portion 8 of the joint body 2 and the push ring 7 on the upper surface side of the rubber packing 6. The basic function and effect of the styrofoam 21 are the same as in the case of the first embodiment.

By the way, the present invention is not limited to the above-mentioned embodiments, but can be appropriately modified. For example, in the third embodiment shown in FIG. 6, the shape of the expanded polystyrene 17 may be expanded polystyrene 18 having no U-shaped groove shown in FIG. 7, or as shown in FIG. It may be a polystyrene foam 19 having a narrow width and a notch 20. Furthermore, according to the present invention, a stop ring is fixed to the outer peripheral side of the push ring of the joining pipe 1, and the stop plate of the stop ring is locked to the collar portion of the fastening bolt to prevent the joining pipe 1 from coming off. It can also be applied to joints.

[0029]

As described above, according to the present invention,
When pressure is applied with a force above a certain level, it causes a significant volume change and shrinks and deforms, and polystyrene foam, which is difficult to deform unless a force above a certain level is applied, acts as a spacer between the protruding part of the pipe or joint body and the push ring. I am wearing it. Therefore, in a temporarily tightened state in which a certain amount of force does not act, an interval corresponding to the thickness of the Styrofoam can be secured between the push ring and the protruding portion of the joint body, and the rubber packing is not reduced in diameter. . Therefore, it is possible to insert the tip of the joint pipe from the outside into the cavity of the joint body by inserting the tip of the joint pipe from the outside into the cavity of the joint body in the state of temporary tightening, which simplifies the pipe joint construction work. Never lose a bolt or nut.

When the styrofoam is annular, soil, stones, etc. do not enter between the protruding portion of the joint body and the push ring, which does not cause a fastening failure. Moreover, since the screw portion of the tightening bolt between the protruding portion of the joint body and the push ring does not come into contact with the soil, it is possible to prevent corrosion of the portion. Has been.

[Brief description of drawings]

FIG. 1 is a partial vertical sectional view showing a pipe joint in a temporarily tightened state according to a first embodiment of the present invention.

FIG. 2 is a partial vertical cross-sectional view showing a state in which the joining pipe is inserted into the pipe joint in the temporarily tightened state according to the first embodiment of the present invention.

FIG. 3 is a partial vertical cross-sectional view showing a fully tightened state of the pipe joint according to the first embodiment of the present invention.

FIG. 4 is a perspective view showing styrofoam according to the first embodiment of the present invention.

FIG. 5 is a perspective view showing styrofoam according to a second embodiment of the present invention.

FIG. 6 is a front view showing styrofoam and a protrusion of a joint body according to a third embodiment of the present invention.

FIG. 7 is a front view showing a modified example of the Styrofoam of the third embodiment of the present invention.

FIG. 8 is a front view showing another modification of the polystyrene foam of the third embodiment of the present invention.

FIG. 9 is a semi-longitudinal sectional view showing a pipe joint according to a fourth embodiment of the present invention.

FIG. 10 is a perspective view showing styrofoam according to a fourth embodiment of the present invention.

FIG. 11 is a partial vertical sectional view showing the entire conventional pipe joint.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Joining pipe 2 ... Joint body 4 ... Cavity 6 ... Rubber packing 7 ... Retaining ring 11 ... Tightening bolt 12 ... Nut 13 ... Styrofoam 16 ... Styrofoam 17 ... Styrofoam 18 ... Styrofoam 19 ... Styrofoam 21 ... Styrofoam

Claims (1)

[Claims] 1. A pipe or a joint body having a tapered receiving portion, in which a screwless joint pipe is inserted, an annular rubber packing is inserted and inserted, and a pipe or bolt is used by a bolt and a nut which are tightening means of a push ring. In an expansion and contraction flexible pipe joint that is tightened to the joint body, a styrofoam that secures a predetermined tightening margin is interposed between the protruding portion of the pipe or the joint body and the push ring, and the push ring, the rubber packing, the pipe or the joint body. Temporary fastening structure for expansion and contraction flexible pipe joints, characterized in that and are temporarily fastened together.