JPH0771668A - Pipe fitting for lining pipe - Google Patents

Abstract

PURPOSE:To improve a corrosion preventing effect of a fitting main unit by inserting a lining pipe, mounting a pipe end mounting member on an internal surface of the fitting main unit, and when it is engaged with a pressing ring, by sealing a part between the fitting main unit and the lining pipe through a packing member. CONSTITUTION:In the case that a nut 42 is screwed to the end part of a fitting main unit 40 consisting of cast provided with coating formed by injection molding synthetic resin in the internal surface, to mount a lining pipe 44 on this fitting main unit 40, a pipe end mounting member 43 is mounted on a pipe end part of the lining pipe 44. This pipe end mounting member 43 is constituted of a rubber-made cap part 49 comprising a jaw 46 in close contact with the internal surface of a pipe end part 45, flange 47 brought into contact with a pipe end surface and a cylinder 48 extended to an external surface of the pipe end part in the point end part, packing part 50 compressed in the end part of the fitting main unit 40 and a coming off stop part 52 held with the packing part 50 by arranging a plurality of grip members 51 on the circumference. Thus when tightened the nut 42, the packing part 50 is compressed to seal a part between the pipe 44 and the main unit 40.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a pipe joint for a lining pipe in which the inner surface of a metal pipe is covered with a synthetic resin, and more specifically, it can be connected without providing a screw at the end of the pipe, and the end face of the lining pipe can be connected. The present invention relates to a pipe joint designed to prevent corrosion.

[0002]

2. Description of the Related Art Japanese Utility Model Publication No. 2-8153 shown in FIG.
The annular packing 3 is extended to the tip of the pipe insertion port 23 and brought into close contact with the pipe end face 24, and the extended portion 32 has an annular thin portion 36.
Is provided, and an annular groove 13 is provided on the inner peripheral surface of the pipe receiving port 11 corresponding to the thin portion 36.
The annular packing 3 extends to the tip of the pipe insertion port 23 and comes into close contact with the pipe end face 24, thereby preventing the pipe end face 24 from coming into contact with water in the pipe and corroding.

An annular thin portion 36 provided on the extending portion 32
Adjusts the length of the packing 3 according to the insertion depth of the pipe, and when the insertion depth of the pipe is shallow, the annular packing 3 is compressed by being pressed by the push ring 4 to reduce the thickness of the packing 3. The part 36 is bent. The bent thin portion 36 is accommodated in the concave groove 13 provided in the inner peripheral surface of the pipe receiving port 11, thereby facilitating the length adjustment of the packing 3.

[0004]

However, in the above-mentioned prior art, when the insertion depth of the pipe is shallow, the thin portion 36 tends to move forward when the packing 3 is compressed by the push ring 4.
In order to prevent this, a ring 34 is provided on the outer surface of the extension 32, but the tip 33 of the extension 32 tends to move away from the tube end surface 24. Therefore, the tube end surface 24 is always the tip 33
Therefore, the tube end surface 24 is not contacted with water, and a gap is formed in the tube end surface 24 to come into contact with water in the tube, so that the tube end surface 24 is corroded. Further, since the tube 2 is held only by the holding force by the compression of the packing 3, the tube 2 can easily come out of the socket-attached tube 1. The present invention solves the above problems and provides a pipe joint for a lining pipe in which the end surface of the lining pipe to be connected is reliably shielded from water in the pipe to prevent corrosion and the pipe does not come out. Is.

[0005]

SUMMARY OF THE INVENTION The gist of the present invention consists of a joint body that receives a lining pipe, a push ring that engages with the joint body, and packing that is mounted between the joint body and the outer peripheral surface of the lining pipe. In the pipe joint, at the pipe end portion of the lining pipe, a cap portion that closely adheres to the inner surface of the pipe end portion and surrounds the end surface and the outer surface from the inner surface, a rubber packing portion following the cap portion, and this packing portion Then, a pipe end mounting member, which is integrated with a retaining portion that locks the lining pipe, is mounted, and the inner surface of the joint body is covered with a synthetic resin at least up to a portion in contact with the packing portion. A pipe joint for a lining pipe, characterized in that a lining pipe is connected by pressing a packing portion of the retaining member and the retaining member by tightening a push ring on the joint body.

[0006]

Since the present invention has the above-mentioned structure, when the lining pipe having the pipe end mounting member is inserted into the synthetic resin-coated inner surface of the joint body and the joint body and the push ring are engaged, The retaining portion of the pipe end mounting member is pushed in the axial direction by the inner surface of the push ring and locked to the outer surface of the lining pipe to push the lining pipe in the pipe axial direction. Further, the packing portion of the pipe end mounting member is pushed in the pipe axial direction by the push ring to seal between the joint body and the lining pipe. Therefore, by tightening the push ring, the lining pipe and the pipe end mounting member are integrally pushed and moved in the pipe axial direction.

Therefore, the cap portion of the pipe end mounting member does not come off from the pipe end portion, and since the cap portion is in close contact with the inner surface of the pipe end portion, it blocks the water in the pipe and the pipe end surface is always kept. Corrosion protected. Further, since the inner surface of the joint body is covered with the synthetic resin at least to the portion in contact with the packing portion, the joint body also does not corrode. Further, the retaining portion of the pipe end mounting member prevents the lining pipe from coming off.

[0008]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a longitudinal sectional view of a main part with a part omitted showing a first embodiment of the present invention, in which 40 is a joint body made of casting, 41
Is a synthetic resin that is injection-molded and coated on the inner surface of the joint body 40, 42 is a cast nut that is screwed into the male screw of the joint body, 43 is a pipe end mounting member described later, and 44 is a lining that is resin-coated on the inner surface. It is a steel pipe.

The pipe end mounting member 43 is mounted on the pipe end portion of the lining pipe 44 before screwing the nut, and has a jaw 46 which is in close contact with the inner surface of the pipe end portion 45 at the tip portion and a collar 4 which contacts the pipe end surface.
7 and a rubber cap portion 49 composed of a cylinder 48 extending to the outer surface of the pipe end portion, and a joint body 40 following the cap portion 49.
Has a packing portion 50 that is compressed at the end portion thereof, and a retaining portion 52 at the rear end portion of which a plurality of grip members 51 are circumferentially arranged and held by the packing portion 50. The grip member 51 is made of steel, has a spherical outer surface, and has a cutting edge formed around the inner surface.

Further, the rear end portion 53 of the pipe mounting member projects from the rear end portion of the nut while the nut 42 is tightened, and it is possible to confirm whether or not the tightening of the nut is completed from the outside. Further, a stainless steel retainer 58 is attached to the inner surface of the jaw 46 of the cap portion, and the jaw 46 is locked while being compressed to the inner surface of the lining tube 44.

When the pipe end mounting member 43 is mounted on the lining pipe 44 and is inserted into the joint body 40 and the nut 42 is tightened, the grip member 51 is pushed in the axial direction by the tapered inner surface of the nut, so that it is locked to the pipe 44. At the same time, the tube 44 is pushed in the axial direction as the nut is screwed. And packing part 50
Is compressed at the end of body 40 to provide a seal between tube 44 and body 40. Further, since the pipe 44 is pressed together with the packing portion 50, the pipe end portion 45 is always held in the cap portion 49, and the pipe end portion 45 does not come out from the cap portion 49.

Further, since the jaw 46 of the cap portion is in close contact with the inner surface of the pipe end portion 45 by the retainer 58, the pipe end surface 45
The water in the pipe does not enter the pipe, and the corrosion of the pipe end face can be reliably achieved.
Further, even if the pulling force is applied to the connected lining pipe 44 by mounting the retainer 58 or the pipe 44 is pulled back before tightening the nut 42, the jaw 46 of the cap portion 49 is pulled.
Is closely attached to the inner surface of the pipe 44, the pipe end portion 45 does not come out of the cap portion 49. Further, since the watertightness of the cap portion is good, water in the pipe does not enter the pipe end portion along the jaw 46 and the inner surface of the pipe.

The retaining portion of the tube end mounting member 43 may be held by tilting the disc spring 54 as shown in FIG. 2 in place of the grip member 51, and as shown in FIG. A retainer 57 made of steel and having a tapered outer surface and a saw-toothed biting portion formed on the inner surface and a notch formed on a part of the circumference to facilitate diameter reduction is provided. It may be integrally baked and integrated with the rear end of the packing 62. Further, as shown in FIG. 4, a steel ball 55 or a retaining member 52 formed by winding a coil spring 56 in an annular shape may be used. The cap portion 49 is made of the same rubber as the packing portion 50, which is excellent in terms of watertightness, but is made of plastic to form the packing portion 5.
It may be fixed to 0 and integrated with the retaining portion 52. The other members are almost the same as those in the above embodiment.

[0014]

As described above, in the pipe joint for lining pipe of the present invention, the pipe end and the inner surface of the joint are surely protected from corrosion, so that red water is not generated. Also, there is no removal of the pipe after connection.

[Brief description of drawings]

FIG. 1 is a vertical cross-sectional view of an essential part after connecting a pipe, showing an embodiment of the present invention.

FIG. 2 is a longitudinal sectional view of an essential part after connecting a pipe, showing another embodiment of the present invention.

FIG. 3 is a longitudinal sectional view of an essential part after pipe connection showing another embodiment of the present invention.

FIG. 4 is a longitudinal sectional view of an essential part after pipe connection showing another embodiment of the present invention.

FIG. 5 is a vertical cross-sectional view of an essential part after pipe connection showing a conventional technique.

[Explanation of symbols]

 40 joint body 41 synthetic resin 42 nut 43 pipe end mounting member 44 lining pipe 45 pipe end portion 46 jaw 47 collar 48 cylinder 49 cap portion 50 packing portion 51 grip member 52 retaining portion 53 rear end portion of pipe mounting member 54 disc spring 55 steel ball 56 coil spring 57 retainer with a substantially triangular cross section

Claims (1)

[Claims] 1. A joint body for receiving a lining pipe,
In a pipe joint consisting of a push ring that engages with the joint body and a packing that is mounted between the joint body and the outer peripheral surface of the lining pipe, the pipe end of the lining pipe is in close contact with the inner surface of the pipe end. A pipe end mounting member in which a cap portion that surrounds the end surface and the outer surface from the inner surface, a rubber packing portion that follows this cap portion, and a retaining portion that locks the lining pipe that follows this packing portion are integrated. The inner surface of the joint body is covered with a synthetic resin at least up to a portion in contact with the packing portion, and the packing portion of the retaining member and the retaining member are pressed by tightening a push ring on the joint body. A pipe joint for a lining pipe, which is characterized by connecting the lining pipes.