JPH0914507A - Pipe joint for progressive work method - Google Patents

Abstract

PURPOSE: To provide a pipe joint for progressive work method not generating a defect in a part of a pipe even during progressive work along a curved route. CONSTITUTION: A cut groove part 3c is formed on the inner surface side of a curved part in the outer peripheral surface 3b of an insertion port 3, and this part is made thinner by the depth of the cut groove part 3c so that the tip side of the insertion port 3 may become easily deformable. In any place where a progressive route is made in a curved shape, mutually mating pipes 1 are advanced while being bent at a pipe joint part and even if stress is apt to concentrate in an area on the internal surface side of the bent part between the tip surface 3a of the insertion port 3 and the deepest end surface 2a of a receiving port 2, a sufficient hooking margin is secured by deformation in the diameter expanding direction of more tip end side than the cut groove part 3c in the insertion port 3 so that the stress may be dispersed. Therefore, it can be prevented that shearing force is concentrated in a part of the deepest end surface of the receiving port, resulting in some breakage taking place there.

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 propulsion method, and more particularly to a pipe joint for a propulsion method used for propelling a plurality of pipes not only in a straight line but also in a curved line in the ground.

[0002]

2. Description of the Related Art Conventionally, in propulsion work, an insertion opening formed in a second pipe is inserted into a receiving opening formed in a first pipe, and a front end surface of the insertion opening is inserted into a rear end surface of the receiving opening. There is known a propulsion method in which these pipes are propelled in the ground by bringing the pipes into contact with each other and transmitting the propulsive force between the receiving and inserting ports. In this case, generally, a front conduit is installed at the head of the pipe, and the pipe is propelled while excavating and correcting the direction. The propulsion method pipe used in this propulsion method has a configuration as shown in FIG.

In FIG. 5, reference numeral 1 denotes a cast iron tube body having a receiving port 2 formed at one end and an insertion port 3 formed at the other end. Then, the insertion opening 3 of the other tube 1 is inserted into the reception opening 2 of the one tube 1, and the tip end surface 3a of the insertion opening 3 is received in the reception opening 2
The propulsive force is transmitted from the side of the insertion port 3 to the side of the receiving port 2 by coming into contact with the rear end surface 2a of the. An annular seal material 4 is arranged in a compressed state between the groove portion 2b formed on the inner periphery of the receiving opening 2 and the outer peripheral surface 3b of the insertion opening 3.

The outer circumference of the tube body is covered with an exterior material 5 except for the insertion port 3. The exterior material 5 is formed so that its outer diameter is equal to the outer diameter of the receiving port 2 to prevent the generation of propulsion resistance due to the presence of the receiving port 2. The exterior material 5 is composed of an exterior lining layer 6 formed of a mortar material that covers the outer periphery of the pipe body 1, and an exterior plate 7 formed of a thin steel pipe material that further covers the exterior lining layer 6. .

[0005]

However, when the pipe joint of the above-mentioned propulsion method is used to propel the curved portion of the propulsion path while bending the pipes at the pipe joint portion, As shown in FIG. 7, only the portion A on the inner surface side of the curved portion between the distal end surface 3a of the insertion opening 3 and the rear end surface 2a of the receiving opening 2 is in a point contact state to cause stress concentration, and the propulsive force in the receiving opening 2 is increased. The engagement margin B of the portion to be transmitted becomes extremely small, and a large shearing force acts on the portion A on the inner surface side of the curved portion of the rear end surface 2a of the receiving port 2 which is the engagement margin B to cause a loss (loss). The locations are indicated by the shaded areas).

The present invention solves the above problem. Even when propelling a curved path, stress is concentrated on a part of the pipes due to the propulsive force, or a defect due to a reduction in the clearance between the pipes is caused. It is an object of the present invention to provide a pipe joint for a propulsion method that does not occur.

[0007]

In order to solve the above problems, the present invention inserts an insertion opening formed in a second tube into a receiving opening formed in a first tube, In the pipe joint for the propulsion method, in which the tip end surface is brought into contact with the back end face of the socket and the propulsive force is transmitted between the socket insertion ports to propel these pipes linearly and curvedly in the ground, A cutout groove portion is formed on at least the inner surface side of the curved portion in the outer peripheral surface of the insertion opening of the pipe.

Further, according to the present invention, the insertion opening formed in the second pipe is inserted into the inside of the receiving opening formed in the first pipe, and the front end surface of the insertion opening is brought into contact with the rear end surface of the receiving opening. , A pipe joint for a propulsion method for propelling these pipes linearly and curvedly in the ground by transmitting a propulsive force between the receiving and inserting openings.
The cutout groove portion is formed at least on the inner surface side of the curved portion in the rear end surface of the receiving opening of the pipe.

[0009]

In the above structure, since the notch groove portion is formed at least on the inner surface side of the curved portion of the outer peripheral surface of the insertion opening of the second pipe, the tip end side is deformed with the portion where the notch groove portion is formed in the insertion opening as a base point. It will be easier. Therefore, stress is concentrated on the inner surface of the curved part between the tip surface of the insertion opening and the back end surface of the receiving opening by bending the pipes at the pipe joint portion while bending the propulsion path. In this case, the tip end side of the notch groove portion in the insertion opening is slightly deformed in the radial direction, and a sufficient margin is secured between the tip end surface of the insertion opening and the rear end surface of the receiving opening. As a result, the stress is dispersed, and as a result, the shearing force is not concentrated and damaged on a part of the rear end surface of the receiving opening as in the conventional case.

Further, since the cutout groove portion is formed at least on the inner surface side of the curved portion in the innermost end surface of the receiving opening of the first pipe, the inner peripheral side is easily deformed from the portion where the cutout groove portion is formed in the receiving opening. Become. Therefore, stress is concentrated on the inner surface of the curved part between the tip surface of the insertion opening and the back end surface of the receiving opening by bending the pipes at the pipe joint portion while bending the propulsion path. In this case, the inner peripheral side of the cutout groove portion of the receiving opening is slightly deformed in the diameter reducing direction, and a sufficient margin is secured between the front end surface of the insertion opening and the rear end surface of the receiving opening. As a result, the stress is dispersed, and as a result, the shearing force is not concentrated and damaged on a part of the rear end surface of the receiving opening as in the conventional case.

[0011]

An embodiment of the present invention will be described below with reference to the drawings. FIG. 1 is a plan sectional view of a pipe joint for a propulsion method according to the present invention, and FIG. 2 is a plan sectional view of an essential part of the pipe joint for a propulsion method. 1 and 2, those having the same functions as those of the conventional one shown in FIGS. 5 to 7 are designated by the same reference numerals, and the description thereof will be omitted.

As shown in FIGS. 1 and 2, a notch groove portion 3c is formed on the inner surface side of the curved portion of the outer peripheral surface 3b of the insertion opening 3 of the tube 1 so as to be cut inward toward the inner side of the tube 1. There is. For example, the notch groove portion 3c is formed at a position where it does not come into contact with the annular sealing material 4 and does not adversely affect the sealing performance, while being separated from the tip of the insertion opening 3 by an appropriate distance.

In the above structure, since the cutout groove portion 3c is formed on the inner surface side of the curved portion of the outer peripheral surface 3b of the insertion opening 3 of the pipe 1, this portion of the insertion opening 3 is cutout groove portion more than other portions. Since the thickness is reduced by the depth of 3c, the distal end side is easily deformed by bending with the portion of the insertion slot 3 where the notch groove portion 3c is formed as a base point.

Therefore, as shown in FIG. 1, at the location where the propulsion path is curved, the pipes 1 are bent and propelled at the pipe joint portion to be propelled, and the tip surface 3a of the insertion port 3 and the receiving port 2 are guided. When the stress tends to concentrate on the inner surface side portion of the curved portion of the rear end surface 2a, the distal end side of the notch groove portion 3c of the insertion opening 3 is deformed in the radial direction, as enlarged and shown in phantom in FIG. As a result, a sufficient margin is secured between the tip surface 3a of the insertion slot 3 and the rear end surface 2a of the receiving slot 2 in the thickness direction and the circumferential direction of the tube 1. As a result, the stress is dispersed, and as a result, it is possible to prevent the shearing force from being concentrated on a part of the rear end surface of the receiving opening and being damaged.

In the above embodiment, the case where the notch groove portion 3c is formed only on the inner surface side of the curved portion of the outer peripheral surface 3b of the insertion opening 3 has been described. The notch groove portion 3c may be formed over the entire circumference of the outer peripheral surface 3b. In this case, the above-described action and effect can be obtained regardless of the direction of the propulsion path, and the orientation of the pipe 1 can be controlled. The work efficiency can be improved without the need for arrangement.

FIGS. 3 and 4 show another embodiment of the present invention. As shown in FIGS. 3 and 4, the pipe 1 is located on the inner surface side of the curved portion of the rear end face 2a of the receiving port 2 of the pipe 1. Is formed with a notched groove portion 2c that is notched toward the inner side. For example, the cutout groove portion 3c is formed at a position closer to the outer periphery of the inner end surface 2a.

In the above structure, the cutout groove portion 2c is formed on the inner surface side of the curved portion of the rear end surface 2a of the receiving opening 2 of the pipe 1, so that the portion of the receiving opening 2 on the inner peripheral side of the cutout groove portion 2c is notched. It is easy to bend and deform the tip end side in a cantilever state with the back end of the groove 2c as a base point.

Therefore, as shown in FIG. 3, at the place where the propulsion path is curved, the pipes 1 are propelled while being bent at the pipe joint portion, and the tip surface 3a of the insertion port 3 and the receiving port 2 are propelled. When the stress is attempted to concentrate on the inner surface side portion of the curved portion of the back end surface 2a, the inner peripheral side of the cutout groove portion 2c of the receiving port 2 in the diameter reducing direction is enlarged as shown by an imaginary line in FIG. A sufficient margin is secured in the circumferential direction and the thickness direction of the tube 1 between the distal end surface 3a of the insertion opening 3 and the rear end surface 2a of the receiving opening 2 by being deformed. As a result, the stress is dispersed, and as a result, it is possible to prevent the shearing force from being concentrated on a part of the rear end surface of the receiving opening and being damaged.

In the above embodiment, the case where the notch groove 2c is formed only on the inner surface side of the curved portion of the rear end surface 2a of the receiving opening 2 has been described, but not only on the inner surface side of the curved portion, but also on the inner surface of the receiving opening 2. The notch groove portion 2c may be formed over the entire circumference of the rear end surface 2a. In this case, the above-described action and effect can be obtained regardless of the direction of the propulsion path, and the direction of the pipe 1 can be controlled. The work efficiency can be improved without the need for arrangement.

Further, by combining the above-mentioned embodiments, the notch groove portions 2c, 2c may be formed at both the outer peripheral surface 3b of the insertion opening 3 and the rear end surface 2a of the receiving opening 2, respectively. A synergistic effect will be obtained.

[0021]

As described above, according to the present invention, the notch groove portion is formed at least on the inner surface side of the curved portion in the outer peripheral surface of the insertion opening of the pipe or the rear end surface of the receiving opening, so that the propulsion path is curved. Even if the pipes are propelled while being bent at the pipe joint at the point where the joint is open, a sufficient margin is secured between the tip end surface of the insertion opening and the back end surface of the receiving opening to disperse the stress. As described above, it is possible to prevent the shearing force from being concentrated on a part of the rear end surface of the receiving port and causing damage.

[Brief description of the drawings]

FIG. 1 is a plan sectional view of a pipe joint for a propulsion method according to an embodiment of the present invention.

FIG. 2 is a plan sectional view schematically showing a main part of the pipe joint for the propulsion method.

FIG. 3 is a plan sectional view of a propulsion pipe joint according to another embodiment of the present invention.

FIG. 4 is a plan sectional view schematically showing a main part of the pipe joint for the propulsion method.

FIG. 5 is a plan sectional view of a main part of a conventional pipe joint for a propulsion method.

FIG. 6 is a main-portion cross-sectional view showing a bent state of the conventional pipe joint for propulsion method.

FIG. 7 is a cross-sectional view schematically showing an operation of the conventional pipe joint for propulsion method.

[Explanation of symbols]

 1 Pipe 2 Receptacle 2a Back End Faces 2c, 3c Notch Groove 3 Insertion Port 3a Tip Surface 3b Outer Surface

Claims (2)

[Claims] 1. A second pipe is provided inside a receptacle formed in a first pipe.
Insert the insertion ports formed in the pipes, contact the tip surface of the insertion ports with the rear end face of the receiving port, and transfer the propulsive force between the receiving port and the insertion port to form a straight line in the ground. A pipe joint for a propulsion method for propelling in a curved shape, wherein a cutout groove portion is formed at least on the inner surface side of the curved portion in the outer peripheral surface of the insertion opening of the second pipe. 2. A second member is provided inside a receptacle formed in the first pipe.
Insert the insertion ports formed in the pipes, contact the tip surface of the insertion ports with the rear end face of the receiving port, and transfer the propulsive force between the receiving port and the insertion port to form a straight line in the ground. A pipe joint for a propulsion method for propelling in a curved shape, characterized in that a notched groove portion is formed at least on the inner surface side of the curved portion in the rear end face of the receiving opening of the first pipe.