JPH01303391A - Non cut-and-over lying change device for existing pipe - Google Patents

Abstract

PURPOSE:To prevent crushed pieces from being forced in the ground by providing an enlarged part on a crushing head while introducing the crushed existing pipe into a barrel in the rear side. CONSTITUTION:A crushed head 1 for switching an existing pipe in the ground to a new pipe under crushing is composed of a cylindrical barrel 3, enlarged part 9 and outer cylinder part 5. The barrel part 3 is connected to the new pipe 2. The enlarged part 9 is adapted to crush the existing pipe 6. The outer cylinder part 5 is adapted to introduce the crushed pieces 6' of the crushed existing pipe 6 and to crush a coupling part 11'.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to a trenchless replacement device for existing pipes, such as asbestos pipes, cast iron pipes, etc., for replacing existing pipes with new pipes without cutting.

2. Description of the Related Art Conventional devices of this type include, for example, the Japanese Patent Publication No. 60-2
As shown in Publication No. 7873, an excavator has a body portion having an outer diameter larger than the outer diameter of the existing pipe, and a front portion that engages with the inner wall of the existing pipe to crush the wall. A new pipe is attached to the rear end of an excavator, and the excavator is moved into the existing pipe with the front part of the excavator first, crushing the existing pipe, and inserting the new pipe into the shattered existing pipe. It has been proposed that a space for inserting a pipe is maintained by the body, and a new pipe is inserted into this space.

Problems to be Solved by the Invention However, according to the above-mentioned conventional device, the fragments of the existing pipes are pushed into the surrounding ground, which has a negative impact on the nearby pipes and the ground surface. If asbestos fibers are made of natural materials, there is a possibility that asbestos fibers may enter groundwater.

Therefore, the present invention aims to solve such problems and to prevent crushed pieces of existing pipes such as asbestos from having an adverse effect on the surrounding area.

Means for Solving the Problems In order to solve the above-mentioned problems, the present invention provides an apparatus for crushing an existing underground pipe with a crushing head and replacing it with a new pipe following the crushing head, in which the crushing head is , a cylindrical body connected to the new pipe, an enlarged part provided in front of this body that widens towards the rear and can crush the existing pipe by the propulsion of this crushing head, and this enlarged part. An outer cylinder that covers the surrounding area at a predetermined interval and guides the crushed existing pipe into the body at the rear, and whose outer circumference widens toward the rear so that the joint part of the existing pipe can be crushed by the thrust of the crushing head. The configuration has a section.

Operation In the above configuration, when the crushing head is propelled, the existing pipe is crushed by the enlarged portion, and the fragments of the crushed existing pipe are guided to the body portion while being guided by the outer cylinder portion. Therefore, crushed pieces of the existing pipe will not be pushed into the surrounding ground, and even if the existing pipe is made of asbestos, asbestos fibers will not enter the groundwater. In addition, after the existing pipe joint part is crushed by the outer cylindrical part by the propulsion of the crushing head, it is spread by the outer peripheral surface and left in the ground.

Example An embodiment of the present invention will be described below with reference to FIG.

In this embodiment, the crushing head 1 has a configuration as shown in FIG. This crushing head 1 includes a cylindrical body part 3 whose rear end is connected to a new pipe 2 and has the same diameter as the new pipe 2, and a head part that is attached to protrude forward from the front inner surface of this body part 3. 4 and an outer cylinder part 5 extending forward from the body part 3.The head part 4 is provided with a guide part 7 at its tip to be inserted into an existing pipe 6 made of asbestos. The portion 7 has a built-in television camera 8 for observing the internal condition of the existing pipe 6 through the conical portion 7a at the tip. The head 4 is provided with an enlarged part 9 that becomes wider in outer diameter toward the rear following the guide part 7, and is further provided with a reduced part 10 whose outer diameter becomes smaller toward the rear. It is connected to the body part 3IPI, and the expansion part 9 acts like a kind of wedge by the propulsion of the crushing head 1, and the existing pipe 6
An enlarged part 9 and a reduced part 10 in the head 4 for crushing the material from the inside are covered with an outer cylinder part 5 at a predetermined interval in the radial direction. The front part of the outer cylinder part 5 has a shape in which the outer diameter becomes wider toward the rear on the front side corresponding to the enlarged part 9 and the reduced part 10 of the head part 4, and becomes smaller towards the rear on the following rear side. Also, the cross-sectional shape of the front part, which widens toward the rear, is tapered at the tip and becomes thicker toward the rear. The tip of the outer cylindrical part 5 is set to a size that can fit between the outer surface of the existing pipe 6 and the inner surface of the gibold joint 11 that is the joint part of the existing pipe 6, and is pushed out by the crushing head 1. The front outer surface of the cylindrical part 5 acts like a wedge to crush the gibold joint 11 from the inside. In addition, the existing pipe 6
is made of asbestos, while the new pipe 2 is made of a material other than asbestos, and both have approximately the same diameter.

With the above configuration, the first of the new pipes 2 is connected to the rear end of the body 3 of the crushing head 1, and the guide part 7 of the crushing head 1 is connected to the rear end of the body 3.
is inserted into the existing pipe 6 from one end, and in this state, when thrust is applied to the existing pipe 61 (111) from the new pipe 2 side by jacking etc., the enlarged part 9 is pushed into the existing pipe 6, and the existing pipe 6 The wedge action of the enlarged portion 9 crushes the existing pipe 6 from the inside.The resulting broken pieces 6' of the existing pipe 6 are separated from the body from the space between the inner surface of the outer cylinder portion 5 and the enlarged portion or the reduced portion 10. 3 and into the new pipe 2. Also, when the crushing head 1 is propelled to the connection position of the existing pipe 6,
The front end of the outer cylindrical part 5 enters the inner surface of the gibold joint 11, and the gibold joint 11 is crushed from the inside by the wedge action of the front part of the outer cylinder part 5 due to the propulsive force of the crushing head 1. The joint piece 11' is left in the ground nearby. Therefore, although the gibold joint piece 11' made of metal or the like is generally left in the surrounding ground, the existing pipe crushed piece 6' made of asbestos is not left in the surrounding ground. As the crushing of the existing pipe 6 progresses, new pipes 2 are connected one after another, and the existing pipe crushed pieces 6' and excavated soil accumulated in the new pipe 2 are removed by a screw conveyor or the like.

In this embodiment, since the diameters of the existing pipe 6 and the new pipe 2 are almost the same, a reduced part 10 is provided behind the enlarged part 9 in the head 4, and the shape of the outer cylinder part 5 is also shaped accordingly. In order to accommodate this, we provided a location that becomes smaller toward the rear, but if the new pipe 2 has a larger diameter than the existing pipe 6, there is no need to provide a corresponding location in the reduced part 10 or the outer cylinder part 5. .

Effects of the Invention As described above, according to the present invention, the crushed pieces of the existing pipe that have been crushed by the crushing head can be collected into the crushing head, so that the crushed pieces of the existing pipe are not pushed into the surrounding ground. Particularly, when the existing pipe is made of asbestos, asbestos fibers, which occur when the pipe is made of asbestos, are prevented from entering underground water.

[Brief explanation of the drawing]

FIG. 1 is a sectional view of an apparatus for trenchless installation of existing pipes, which shows one embodiment of the present invention. 1... Crushing head, 2... New pipe, 3... Body, 5
...Outer cylinder part, 6...Existing pipe, 7...Guide part, 8
...TV camera, 9...Enlarged part, 10...Reduced part, 11...Gibold joint. Agent Yoshihiro Morimoto

Claims (1)

[Claims] 1. A device for crushing an existing underground pipe with a crushing head and replacing it with a new pipe following the crushing head,
The crushing head includes a cylindrical body connected to the new pipe, an enlarged part provided in front of the body, which widens towards the rear and can crush the existing pipe by the propulsion of the crushing head, and The crushing head covers the surrounding area at a predetermined interval and guides the crushed existing pipe into the body at the rear, and its outer circumference widens towards the rear so that the joint part of the existing pipe can be crushed by the thrust of this crushing head. A trenchless installation replacement device for existing pipes having an outer cylindrical part.