JPH02178496A - Re-laying method for existing pipeline and underground excavating device - Google Patents

Abstract

PURPOSE:To remove an existing pipe without leaving it at all by laying a bypass pipe in the underground existing pipeline, enveloping the whole existing pipe in a propulsion pipe, and removing the existing pipe from the propulsion pipe while leaving the bypass pipe. CONSTITUTION:A departure vertical shaft 1 and an arrival vertical shaft 42 are drilled, a bypass pipe 40 is laid, and a propeller main body 3 having a propulsion pipe 13 and a cutting bit 11 or the like is installed in the departure vertical shaft 1. The whole existing pipe 50 is enveloped in the propulsion pipe 13, which is advanced in the ground, and the existing pipe is introduced into a casing rod 10. The preceding propulsion pipe 13 is advanced to the root, the main body 3 and a pipe section 9 are separated, the main body 3 is retreated, and expansion pipes 63 and 64 are separated and retreated into bypass pipes 60 and 66. The succeeding pipe section 9 is hung down, its tip is connected to the rear end of the preceding pipe section 9, and it is further connected to the main body 3. The above procedures are repeated, the propulsion pipe 13 is penetrated through the vertical shaft 42, and the existing pipe 50 is carried out to the outside from the vertical shaft 1.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention provides a method for replacing existing pipes such as sewer pipes with new pipes without using them as they are, and a method useful for the method. This relates to underground digging equipment.

[Prior Art] The need to replace sewer pipes and the like buried underground has increased due to the need to expand the cross section due to progressing deterioration and increasing demand. When replacing a pipe with a new one, the open cut method is used, but this method requires digging up the location where the existing pipe is buried, so it is difficult to transport. 1 (From the standpoint of public sentiment and conservation of the living environment, it is desired to develop a replacement method using propulsion methods. Recent technologies include a method using impact propulsion, which involves crushing the existing pipe and replacing it with a new pipe. , a method has been announced in which the existing pipe is completely demolished from one end and replaced with a new pipe in the same way as normal construction work.

[Problem to be solved by the invention] However, when we look at the condition of existing pipes that are aging, we find that they are mainly reinforced concrete pipes, and there are some aging parts at the bottom of the pipes and the parts covered by concrete foundations. There are still some areas where progress has not been made. Under such conditions, crushing by impact propulsion is insufficient. In addition, the method of crushing and propelling from one end has drawbacks such as getting tangled with reinforcing bars or bits in unaged parts, making it impossible to propel.

[Means for Solving the Problems] A method for replacing an existing pipe line according to the present invention includes the steps of: laying a bypass pipe for guiding flowing sewage into the existing underground pipe line;
The method includes a step of propelling the existing pipe underground in a state in which the entire existing pipe is wrapped inside the propulsion pipe, and a step of removing the existing pipe wrapped inside the propulsion pipe from the inside of the propulsion pipe, leaving a bypass pipe. It is characterized by

In the above method, a step of installing a main purpose pipe inside the replaced propulsion pipe and filling a gap between the main purpose pipe and the propulsion pipe with a filler may be provided.

In addition, in one step of the second method of removing the existing pipe line wrapped inside the propulsion pipe from within the propulsion pipe, an adjustment member for supporting the bypass pipe within the propulsion pipe is removed from the propulsion pipe while the existing pipe line is being pulled out. It is also possible to store them in

In addition, in one step of the third method of laying the main purpose pipe inside the propulsion pipe that was not replaced, the main purpose pipe with a spacer on the outside and a support member for the bypass pipe on the inside is inserted into the propulsion pipe. However, the adjusting member may be pushed out of the propulsion pipe, and the bypass pipe may be supported within the main target pipe by a support member.

Furthermore, in the first method, a part of the bypass pipe may be temporarily expanded and contracted, and a subsequent propulsion pipe may be connected to the rear end of the preceding propulsion pipe in that part. good.

The underground excavation device according to the present invention can be directly used in each of the above-mentioned methods, and includes a propulsion pipe press-fitted into the ground, +
(ii) An inner tube that is inserted into the propulsion tube and rotates; a cutting bit that is provided at the tip of the surface inner tube and is rotationally driven to protrude toward the front of the propulsion tube; and +if (inner tube) an operating tube that is provided between the propulsion tube and the operating tube and is capable of direct movement and rotation; It is characterized by comprising an outer cylindrical tube which is swingably attached to the joint inner cylindrical tube with its tip inserted externally, and which is pressed by the propulsion tube during propulsion and is pressed by the operation tube and tilted when direction is corrected. It is said that

In the underground excavation device described in No. 111f, a support fitting for supporting the existing pipe line taken into the inner pipe may be provided on the inner surface of the inner pipe.

Further, in the underground excavation device according to claim 6, a packing made of adhesive rubber, water-swellable rubber, and wear-resistant rubber may be provided at least between the outer tube and the inner tube.

Furthermore, in implementing the method according to the present invention, claim 6
Using the above-mentioned underground excavation device made by Kisha, the cutting bit is rotatably driven while pressing the external pipe in an inclined state using the nt movement of the operation pipe to dig in the inclined direction, and then the propulsion pipe is propelled. The excavation direction can be corrected by causing the excavation direction to follow the preceding outer cylindrical tube.

In addition, when carrying out the method according to the present invention, +il'
1.Claim 6, 1, +3η Using the underground excavation device, pull back the inner tube and operation tube that drives the cutting bit in the opposite direction to the propulsion direction and remove them from the propulsion tube, and after replacing the cutting bit, 11
and can be inserted into the propulsion tube.

[Sakukawa] The method of replacing the existing pipelines described above will proceed as follows. (1) Lay a bypass pipe within the underground general-purpose pipe. (2) The entire existing pipeline is enclosed inside the propulsion pipe and propelled underground. (3) A part of the bypass pipe is temporarily cut off and contracted, and a subsequent propulsion pipe is connected to the rear end of the preceding propulsion pipe at this part. A subsequent propulsion tube is inserted through the shortened bypass tube to extend it, and the bypass tube is connected again. Propulsion continues in the same manner while maintaining the propulsion tube. (4) Remove the existing pipe line wrapped inside the propulsion pipe. (5) In the step (2) above, in order to support the bypass pipe remaining in the propulsion pipe, when the existing pipe line is pulled out from the propulsion pipe, an adjustment member that supports the bypass pipe is inserted into the propulsion pipe. I will store it. (6)
A spacer is provided on the outside of the main purpose pipe, and a support member for the bypass pipe is provided on the inside. This main purpose tube is inserted into the propulsion tube. The surface adjustment member is pushed by the main purpose pipe and is pushed out of the propulsion pipe, and the bypass pipe is supported within the main purpose pipe by the support member.

According to the underground excavation device described above, during normal propulsion, the inner tube is rotationally driven to drive the cutting bit, and the propulsion tube is also propelled to dig underground. The existing pipe line taken into the inner pipe is supported by a support fitting provided inside the inner pipe. When it is desired to correct the direction of excavation, the direction to be corrected is first determined by rotating the inner tube and the outer tube by rotating the operating tube. Next, the operating tube is propelled to push the outer cylinder tube in a desired direction and the cutting bit is rotatably driven to dig in the inclined direction, and then the propulsion tube is propelled to advance the +ftf
Attach the t-section outer cylindrical tube. By repeating this procedure as appropriate, any direction correction can be made. Next, when it is desired to replace the cutting bit, the inner tube and the operating tube can be pulled back to the side opposite to the propulsion direction and removed from the propulsion tube, and after replacing the cutting bit, it can be inserted into the propulsion tube again. In addition,
A gasket is provided at least between the outer tube and the inner tube, and water that enters the curved part during propulsion expands the water-swellable rubber and pushes up the wear-resistant rubber, so the part concerned The watertightness of the product is ensured.

[Example] First, an outline of a method for replacing an existing pipeline according to this example will be explained. In addition to the underground excavation equipment of the embodiments described below, this method is also applicable to, for example, Japanese Patent Publication No. 5,654,438 (Patent No.
This can be carried out using a propulsion device such as that described in No. 387), and it is possible to wrap the existing pipeline by using a propulsion pipe with an inner diameter larger than the outer diameter of the existing pipeline buried underground. In this method, the pipe is propelled from one end of the existing pipeline to the other end. In this case, a bypass pipe for flowing sewage is laid in advance inside the existing pipe, so that construction can proceed without stopping the function of the existing pipe. The propulsion tube penetrates 2. -The existing pipeline inside the propulsion pipe will be pulled out and removed. Next, a main purpose pipe (hereinafter referred to as a main pipe) is installed inside the propulsion pipe, which is a sheath pipe. The main pipe is supported within the propulsion pipe by a spacer that adjusts the flow gradient, and the intended pipe line is constructed by filling the clearance between the propulsion pipe and the main pipe with a filler material.

Next, an underground excavation device according to this embodiment will be explained with reference to FIGS. 1 to 3. As shown in FIG. 1, a propulsion unit 3 is attached to a fixed base 2 installed at the bottom of a starting shaft 1 via a slider 5 in the longitudinal direction (in the horizontal direction in the figure) by the operation of a propulsion jack 4. It is installed so that it can slide freely. This propulsion device main body 3 has a presser metal 6 and a joint pipe 8 that is rotationally driven by a motor 7.
The base of the pipe section 9 that is propelled into the ground can be detachably attached.

That is, a casing rod 10 serving as an inner pipe having a cutting bit 11 at its tip and a discharge screw 12 provided on its inner circumferential surface is connected to a face joint pipe 8 with a chuck 8a. In addition, a propulsion pipe 1 is installed in the casing lot IO.
3 is inserted externally, and the rear end of the propulsion tube 13 is connected to the pusher 6. As will be explained in detail later, in the device of this embodiment, the casing rod 10 and the propulsion pipe 13
A jacking rod 14 as an operating pipe is provided between the two, and this jacking rod 14 is connected to the joint pipe 8 or the pusher 6 as necessary so that it can be freely translated or rotated. .

Further, a pressurized water supply means (not shown) is connected and communicated with the propulsion device main body 3 via a hydraulic hose 15, and this pressurized water is jetted out from the tip of the casing rod 10 to prevent the ground from collapsing during drilling work. That's what I do. Further, numeral 16 in the figure is a hydraulic unit, which supplies pressure oil to the motor 7 and the propulsion jack 4 via a hydraulic hose 17.

Next, the tube section 9 attached to the propulsion device main body 3 will be explained, particularly focusing on the structure of the tip section.

As shown in FIG. 2, a cutting edge main body 20 is provided at the tip of the five-casing rod 1o. This cutting edge main body 20 has a diameter slightly larger than that of the casing rod io, and a plurality of cutting bits 11 are provided on its open front end surface. As shown in FIGS. 4 and 5, the cutting bit 11 is rotatably attached to the front end surface of the cutting edge main body 20 of the casing rod 10 by a shaft 21, and a pair of stoppers 22 are provided on both sides of the cutting bit 11. 23 are provided respectively. Therefore, when the casing rod 10 rotates in the driving direction (clockwise direction in the figure) as shown in FIG. A hole with a size corresponding to the outer diameter can be drilled. On the other hand, when the casing rod 10 is reversed as shown in FIG. 5, the cutting bit 11 fits within the outer diameter of the cutting edge body 20, so the casing rod 10 is pulled out from the propulsion tube 13 in order to replace the cutting edge, etc. I can do it.

An inner cutting bit 24 is attached to the inner surface of the cutting edge main body 20 of the casing rod 10. Among these, cutting bit 2
4 is the casing rod! This is to scrape off the expanded diameter connection part of the existing pipe that will be brought in within θ to make the outer diameter the same, and the amount of inward protrusion is adjusted according to the dimensions of the target existing pipe. It is now possible to do so.

A support fitting 25 is provided on the inner surface of the casing rod 10 to support the installed existing pipe line. This support metal fitting 25 is a bearing-like member that is supported by a receiving portion 25a and moves in any direction, and the inner cutting bit 25
1. Support the existing pipes whose outer diameters are aligned by 1. It is located in a location where you can get ￥.

Next, a jacking rod 14 is fitted onto the casing rod 10 via a bearing 26, and a propulsion pipe 13 is provided by fitting the jacking rod 14 into the casing rod 10. As shown in Figure 2, the casing rod lO
The tip of the shirt king rod 14 is in a position retracted rearward, and the tip of the propulsion tube 13 is in a position further retracted with respect to the cutting edge main body 20 provided at the tip. Furthermore, a protrusion 27 is provided at the tip of the jacking rod 14 for pressing and operating a guide tube 30, which will be described later.

Next, the aforementioned propulsion pipe 13, jacking rod 14,
A leading pipe 30 for correcting the propulsion direction is provided at each tip of the casing rod 10. This lead pipe 30
is a short inner cylindrical pipe 28 that extends the jacking rod 14.
have. As shown in FIG. 3, a protrusion 31 is provided on the outer peripheral surface of the jacking rod 14, and a protrusion 32 is also provided on the inner peripheral surface of the inner cylindrical tube 28, and these protrusions 31. It is designed to engage only in the direction of rotation. That is, when the jacking rod 14 rotates, the inner tube 28 also rotates due to the engagement of the protrusions 31 and 32, but even if the jacking rod 14 moves linearly in the axial direction,
The inner cylindrical tube 28 is not interlocked. Next, the inner cylindrical tube 28 is entirely covered by the rear portion of the outer cylindrical tube 29. The tip of the inner cylindrical tube 28 and the outer cylindrical tube 2
The inner circumferential surface of the substantially central portion of the hinge 33 is a portion of the circumferential direction of the hinge 33.
are connected with. The outer cylindrical tube 29 has the cutting edge main body 20 inserted thereinto via a bearing 34 at its forward portion. Further, the forward portion of the propulsion tube 13 is extrapolated to the rear portion at a predetermined interval. Next, an upper jaw 35 and a lower jaw 36 are provided on the inner circumferential surface of the central part of this outer cylinder tube 29.
A stepped portion is formed. The tip of the propulsion tube 13 is
The outer cylinder tube 29 can be pressed by coming into contact with the upper jaw 35, and the tip of the pressed outer cylinder tube 29 is connected to the cutting bit 1.
1 is pressed from the back. Further, the protruding portion 27 of the jacking rod 14 contacts the lower jaw 36 and applies an eccentric force to the outer tube 29, thereby causing the hinge 3
The outer cylindrical tube 29 can be swung around 3, and the cylindrical tube 29 can be tilted outwardly with respect to the inner cylindrical tube 28.

Next, as shown in FIGS. 6 to 8, a seal 37, which is a ring-shaped water-stopping member, is provided between the cutting edge main body 20 and the outer tube 29. This packing 37 has a structure in which three layers, an adhesive rubber plate 38, a water-swellable rubber 39, and an abrasion-resistant rubber 40, are laminated together. The water-swellable rubber 39 is a rubber mixed with a highly water-absorbing substance, and expands by absorbing water. Further, the surface of the wear-resistant rubber 40 that comes into contact with a mating member and forms a sealing surface is formed in a circumferential shape. A circumferential groove 20a larger than the width of the gasket 37 is formed on the outer circumferential surface of the cutting edge body 20, and the gasket 37 is mounted in the circumferential groove 20a by an adhesive rubber plate 38. When dry, there is a gap between the packing 37 and the outer cylindrical tube 29, but when water enters the circumferential groove 20a during use of this device, the water-swellable rubber 39 absorbs moisture and expands. The wear-resistant rubber 40 is pushed up and pressed against the inner surface of the outer tube 29. That is, when digging underground, the abrasion-resistant rubber 40 comes into close contact with the inner surface of the outer cylindrical tube 29 with its circumferential convex surface crushed, so that moisture and earth and sand do not flow into the tube. Further, as shown in FIGS. 2 and 7, a packing 37 having the same structure as the packing 37 is provided on the outer tube 29 side between the 5 outer tube 29 and the propulsion tube 13. Note that when the outer tube 29 swings around the hinge 33, the outer tube 29 is inclined with respect to the propulsion tube 13, so the distance between the rear end of the outer tube 29 and the outer peripheral surface of the propulsion tube 13 is It depends on the position in the direction. In this case, it is necessary to adjust the dimensions of the gasket 37 when it is inflated so that the gasket 37 absorbs the difference in spacing depending on the location and always ensures water-tightness. Alternatively, a hollow annular sealing member may be provided between the inner circumferential surface of the rear end of the outer tube 29 and the propulsion tube 13 to seal a fluid such as air inside. If the sealing member has such a structure, it will be crushed at the position where the gap becomes narrow, and will conversely swell at the position where the gap becomes wide, so that it will always come into close contact with the sealing surface to ensure water-tightness.

Next, a method for replacing an existing pipeline using the underground excavation device (apparatus) described above will be described. In this embodiment, a sewer pipe is taken up as an example of an existing pipe.

- As shown in FIG. 9, first, the manhole 41 of the existing pipeline 50 laid underground is removed, and the starting shaft 1 and the reaching shaft 42 are excavated.

■As shown in FIG.
2, and connects the existing pipe line 50a on the inflow side of the arrival shaft 42 and the existing pipe line 50b on the downstream side of the starting shaft 1.

Here, the structure of the bypass pipe 60 will be explained. First, the bypass pipe 60 in the reaching shaft 42 has stop valves 61 and 62.
is provided. This bypass pipe 60 is connected to the reaching shaft 4
It is inserted into the existing pipe line 50a on the inflow side of No. 2, and is caulked to prevent leakage of running water. This bypass pipe 60 passes through the existing underground pipe line 50 and reaches almost the starting shaft l. Next, as shown in FIGS. 10 and 18, a pair of telescopic pipes 63 and 64 are provided in the starting shaft 1 as bypass pipes. One telescopic tube 63 is inserted into the bypass pipe 60 via a packing 65 so as to be expandable and retractable. Further, the other telescopic pipe 64 is inserted into the bypass pipe 66, which has been inserted with caulk into the existing pipe line 50b on the flow F side of the starting 4 well 1, so as to be expandable and retractable via a punkin. Each of the opposite ends of the constrictor tubes 63,64 is provided with a stop valve 67,68 and a connecting flange 69,69, respectively.
is the provision.

In the bypass pipe 60 etc. installed in this process
If you open the jtlIJ stop valve 61.67°68, the existing pipe line 50a will be cut off.

50.50b are connected and communicated by the bypass pipe 60 and the telescopic pipe 6364. Furthermore, if the CI I valves 67 and 68 are closed, the sewage water in the bypass pipe 60 will not leak even if the two contraction pipes 63 and 64 are separated by the flanges 69 and 69.

Furthermore, by closing the stop valve 61, water can be allowed to stagnate in the existing pipe 50a on the inflow side. If the amount of flowing F water is large and it is impossible to hold the water, turn off the i$lJ stop valve 6.
Drainage may be carried out by pumping through an above-ground bypass connected to 2.

■As shown in FIG. 11, the propulsion unit 3 of the device is installed in the starting shaft 1. The telescopic pipes 63, 64 in the starting shaft 1 are connected in an extended state. This situation also occurs when the work is temporarily suspended after excavation has started.

(2) As shown in FIG. 12, the pipe section 9 such as the propulsion pipe 13 described above is suspended in the starting shaft l and connected to the propulsion machine main body 3. At this time, the stop valves 61, 67 and 68 are closed, and the telescopic pipes 63 and 64 are cut off and retracted into the bypass pipes 60 and 66, leaving a space for work. After the connection, the telescopic tubes 63 and 64 are extended through the propulsion device main body 3 and connected again.

Then, the propulsion unit main body 3 is driven, and the casing rod 10
It rotates and drives the propulsion pipe 13 to cut into the soil. The propulsion pipe 13 is propelled so as to wrap around the existing pipe line 50. That is, the cutting bit 11 or the existing pipe line 50
The existing pipe line 50 is taken into the casing slot 10 by excavating the area around it and propelling the JfC advance pipe 13. At this time, as shown in FIG.
The circumferentially protruding socket portion 51 is shaved off, and the existing conduit 50 is shaped into a cylindrical shape having a predetermined outer diameter. The existing pipe line 50 taken into the casing rod IO is supported by a support fitting 25 set to match the predetermined outer diameter of the curved portion. During propulsion, the bypass pipe 6
0 and expansion pipes 63 and 64 are the existing pipes 50, 50a, 50
b, so the function of the existing conduit 50 is not impaired. That is, even during construction, the existing pipe line 50 can continue to flow sewage normally as a sewer pipe.

(2) Once the leading propulsion tube 13 is propelled to its base, the propulsion device main body 3 and the tube portion 9 are separated from each other as shown in FIG. 12, and the propulsion device main body 3 is retreated. Then, the stop valves 67, 68 are closed, the telescopic pipes 63, 64 are disconnected, and the bypass pipes 60, 66 are
degenerate within. Then, the subsequent pipe section 9 is suspended into the starting shaft 1.

Next, as shown in FIG. 13, the subsequent tube section 9 is temporarily placed in a predetermined position, and the telescopic tubes 63 and 64 are extended through this tube section 9 and the propulsion device main body 3. Then, after reconnecting the two with the flange 69.69, the stop valve 67.6
Open 8.

Next, the distal end of the succeeding tube section 9 is connected to the rear end of the preceding tube section 9. That is, the casing rod 10, the shirt king slot 14, and the propulsion pipe 13 are connected, respectively. and,
The rear end of this subsequent pipe section 9 is connected to the propulsion device main body 3.

Then, excavation is carried out as explained in step (2).

Repeating the steps above and proceeding with the excavation work while adding pipe parts 9, as shown in Fig. 14, the leading propulsion pipe 13
is passed through the reaching shaft 42.

■As shown in FIG. 15, after the propulsion pipe 13 has penetrated, the casing rod 10 is reversed, the cutting bit 11 is stored inside the cutting edge body 20, and the outer cylindrical pipe 29 and the cylindrical pipe 28 are connected to the reaching shaft 42 side. Collect from. Next, the shirtkin clot 14 is pulled back to the starting shaft 1 side together with the casing lot 10, leaving the 11F advance pipe 13 behind. The telescopic pipes 63 and 64 in the starting shaft 1 are separated and retracted with the restraining hull blower 68 closed. Then, the pulled-back pipe section 9 is removed from the preceding pipe section 9 and the propulsion unit main body 3 and sequentially carried out of the mine. In this process, the existing pipe line 50 is
It was recovered in the state stored in O, and then launched into the starting shaft 1.
It is then transported outside and disposed of.

In this process, when the existing pipe 50 is recovered to the starting gate 1 side, the bypass pipe 60 laid in the existing pipe 50
loses support. Therefore, as shown in FIG.
A supporting member 70 for support is inserted into the propulsion pipe 13 from the side so that the bypass pipe 60 is supported within the propulsion pipe 13.

As shown in FIGS. 20 and 21, this adjustment member 70
The vibrator 71 is divided into two parts along the axis 1T direction, and an adjusting blade 72 is provided thereon, and the dimensions of the adjusting blade 72 are machined according to the inner diameter of the propulsion tube 13. And reaching shaft 42
In this step, the bypass pipe 60 is wrapped and tightened with the vibrator 71 of the separated adjustment member 70, and the adjustment member 70 is fixed to the tip of the cutting bit 11. If you do this,
In conjunction with the pulling back of the casing slot 10, the adjustment member 70 enters the propulsion pipe 13 along the bypass pipe 60. As shown in FIG. 22, if the subsequent adjustment members 70 are successively connected to the preceding adjustment members 70 via the connecting rods 73, these adjustment members 70 will be propelled by the casing slot 10 being pulled out. It is towed within the tube 13 and disposed so as to support the bypass tube 60 within the propulsion tube 1.3.

■As shown in Figure 16, the entire casing rod l
When the O and jacking rods 14 are pulled out and the bypass pipe 60 is supported within the propulsion pipe 13 by the adjustment member 70, the propulsion machine main body 3 is removed from the starting shaft 1 and the telescopic pipes 63 and 64 are reconnected.

Next, as shown in FIG.
Insert 0. In inserting and propelling the main pipe 80, the telescoping tubes 63, 64 are operated in the same manner as in the previous propelling step.

As shown in FIGS. 17 and 23, a spacer 81 is provided on the outer surface of the main pipe 80 to adjust the flow gradient. As this spacer 81, Utility Model No. 62-9417 (Utility Model Registration No. 1701645)
It is also possible to use the adjustment spacer A described in . Furthermore, a support member 82 for supporting the bypass pipe 60 housed within the wood pipe 80 is pre-installed on the inner surface of the wood pipe 80. The support member 82 of this embodiment is composed of a sleeve vibe 83 and support blades 84 having an inner rod that is larger than the outer diameter of the bypass pipe 60 and has an appropriate amount of space. In
Similar to the propulsion pipe connection work in the propulsion process described above, the main pipes 80 having such a structure are successively inserted into the propulsion pipe 13.
We will install it. The adjustment member 70 is sequentially pushed out toward the arrival shaft 42 side by insertion of the main pipe 80 and is recovered, and at the same time, the bypass pipe 60 is supported by the support member 82.

[Phase] Finally, filler is filled between the propulsion pipe 13 and the main pipe 80, and the bypass pipe 60 and support member 82 are removed. Then, manhole 41 will be restored and both shafts 1.42 and 1.42 will be backfilled. In addition, in the above process, when it is desired to exchange the cutting bit 11 especially in the propulsion process, by reversing the casing rod 10 and retracting the cutting bit 11, the casing rod 10 and jacking rod 14 are moved to the starting shaft 1 side. It can be pulled out.

Next, according to the present device, the propulsion direction can be corrected during propulsion.

During normal propulsion, the casing rod 10 is rotated by the motor 7 of the propulsion device body 3, and the cutting edge body 20 and cutting bit 11 are driven to cut the ground. At the same time, thrust is applied to the propulsion tube 13, and the tip of the propulsion tube 13 presses the upper jaw 35 of the outer tube 29 to propel it.

If it is necessary to modify 11 in the forward direction, the propulsion tube 13
is separated from the propulsion machine main body 3, and the shirt king slot 14 is connected instead. When thrust is applied to the propulsion unit 3 or the Shirtking rod 14, the protrusion 27 of the Shirtking rod 14 presses the F jaw 36 of the outer tube 29.
The outer tube 29 swings in a predetermined direction about the hinge 33.

(It is tilted downward in FIG. 2.) This tilting direction rotates the shirt king rod 14, and the outer tube 29 and the inner tube 28
By linking this to this, it can be set to 0 at any time. Then, while driving the casing rod 10 and rotating the cutting bit 11, the jacking rod 1
4 is further advanced to perform cutting in the inclined direction.

In this state, the propulsion tube 13 remains stopped, and only the leading tube 30 consisting of the outer cylindrical tube 29 and the inner cylindrical tube 28 is leading in the inclination direction. Now, when the leading tube 30 has advanced to the limit position where the wrap state between the outer tube 29 and the propulsion tube 13 can be maintained, the propulsion of the jacking rod 14 is stopped, and this time thrust is applied to the propulsion tube 13 to move the propulsion tube 13 into the outer tube. It is propelled until it comes into contact with the upper jaw 35 of the tube 29. By repeating the above operations an appropriate number of times, any direction correction can be made.

As described above, according to the direction correction mechanism and method of the present device, the direction can be easily set without being affected by the earth pressure around the pipe, so the work of correcting the propulsion direction can be done easily and efficiently. can be done. In addition, since the direction can be corrected without forcing the following propulsion tube 13, the problem of increased propulsive force due to poor accuracy or bent holes in the propulsion tube can be solved, and the propulsion distance can be greatly improved. .

[Effects of the Invention] According to the method of replacing an existing pipe according to the present invention, the existing pipe is propelled while being wrapped around it, so a new pipe can be laid while crushing the existing pipe. can be avoided. Since the bypass pipe is installed within the existing pipeline, the existing pipeline can be used as is during construction. Furthermore, for the main purpose pipe installed in the propulsion pipe, the flow gradient characteristic B4g can be performed,
Also, since the finished pipe has a rigid double-pipe structure, there will be no leakage at all.

Further, the underground excavation device of the present invention can be effectively used in the above-mentioned method of replacing an existing pipeline.

Further, according to the present device, it is possible to perform a two-stage propulsion method in which the outer tube and the inner tube are propelled in advance, and then the propulsion tube is made to follow and propel. That is, since the outer cylinder tube, etc., which is propelled in advance in the first stage, can be propelled in the zero direction, it becomes easy to correct the direction of the propulsion tube, which is propelled subsequently. In the conventional normal propulsion method, ML
The reduction in accuracy in the direction of travel caused the propulsive force to become excessive, making long-distance propulsion impossible.However, with this device, direction correction can be made without placing an excessive load on the propulsion tube, making it possible to reliably propel long-distance distances. It can be promoted. Therefore, this device is suitable not only for the method of replacing an existing pipe as described above, but also for replacing an existing pipe with a pipe with a larger cross section, laying a new pipe, and covering the inner surface of the propulsion pipe as a sheath pipe. It can be widely applied to methods such as making roads, draining water from landslide areas, and by roof construction methods.

[Brief explanation of the drawing]

Fig. 1 is a sectional view showing the overall structure of an underground excavation device which is an embodiment of the present invention, Fig. 2 is a sectional view of a pipe section which is the main part of the device, and Fig. 3 is a sectional view of the section shown in Fig. 2. −■ End view of the cut plane,
Figure 4 is a diagram showing the state of the cutting bit when it is rotating in the normal direction in the cutting direction, Figure 5 is a diagram when it is also rotating in the reverse direction, and Figures 6 and 7 are each shown in Figure 2. The indicated ■ part and ■
Figure 8 is an enlarged cross-sectional view of the packing, Figures 9~
Fig. 17 is a process diagram showing a method of replacing an existing pipe line according to an embodiment of the present invention, Fig. 18 is a structural diagram of an expandable pipe, and Fig. 19
20 is a perspective view of the adjustment member, FIG. 21 is a front view of the adjustment member, and FIG. 22 is a perspective view showing the adjustment member introduced into the propulsion tube. Second
Figure 3 is a perspective view of the main pipe with spacers and support members. DESCRIPTION OF SYMBOLS 10... Casing rod as an inner pipe, 1... Cutting bit, 13... Propulsion tube, 4... Jacking rod as an operating tube, 5... Supporting metal fittings, 2
8...Inner tube, 9...Outer tube, 37...
Packing, 8... Rubber plate for adhesion, 39... Water-swellable rubber, 0... Wear-resistant rubber, 0.50a, 50b --- Existing pipe line, 0... Bypass pipe, 364. ... Expandable pipe as a bypass pipe, 0... Adjustment member, 80-... Main purpose pipe (main pipe), 1... Spacer, 82-... Support member.

Claims (1)

[Claims] 1. A step of laying a bypass pipe for guiding flowing sewage into an existing underground pipe, and a step of propelling the existing pipe underground with the entire existing pipe wrapped inside the propulsion pipe. and a step of removing the existing pipeline wrapped inside the propulsion pipe from inside the propulsion pipe, leaving a bypass pipe. 2. Laying the main purpose pipe inside the replaced propulsion pipe,
2. The method for replacing an existing pipe line according to claim 1, further comprising the step of filling a space between the main purpose pipe and the propulsion pipe with a filler material. 3. In the process of removing the existing pipe line wrapped inside the propulsion pipe from inside the propulsion pipe, it is recommended that the adjustment member that supports the bypass pipe inside the propulsion pipe be stored in the propulsion pipe as the existing pipe line is pulled out. The method for replacing an existing pipeline according to claim 2. 4. In the step of laying the main purpose pipe inside the replaced propulsion pipe, insert the main purpose pipe with a spacer on the outside and the support member for the bypass pipe on the inside into the propulsion pipe, and insert the adjustment member outside the propulsion pipe. 4. The method for replacing an existing pipeline according to claim 3, characterized in that the bypass pipe is pushed out and supported within the main target pipe by a support member. 5. A part of the bypass pipe is temporarily separated so that it can expand and contract, and the following propulsion pipe is connected to the rear end of the preceding propulsion pipe at this part. How to replace existing pipelines. 6. A propulsion tube that is press-fitted into the ground, an inner tube that is inserted into the propulsion tube and rotates, and a cutting bit that is provided at the tip of the inner tube and protrudes toward the tip of the propulsion tube and is rotationally driven. , an operation tube provided between the propulsion tube and the inner tube and capable of direct movement and rotation; and an inner tube provided between the propulsion tube and the operation tube and linked to rotation of the operation tube. a tube, and an outer tube that is swingably attached to the inner tube by inserting the tip of the inner tube, and is pressed by the propulsion tube during propulsion and is pressed by the operation tube and tilted when changing direction. An underground excavation device comprising: 7. The underground excavation device according to claim 6, further comprising a support fitting provided on the inner surface of the inner pipe to support an existing pipe line taken into the inner pipe. 8. The underground excavation device according to claim 6, further comprising a packing made of adhesive rubber, water-swellable rubber, and wear-resistant rubber, provided at least between the outer cylindrical tube and the inner tube. 9. Using the underground excavation device according to claim 6, the cutting bit is rotatably driven while pressing the outer cylindrical tube in an inclined state by the propulsion of the operation tube to excavate in the inclined direction, and then the propulsion tube is propelled. 2. The method for replacing an existing pipe line according to claim 1, further comprising the step of correcting the propulsion direction by causing the outer cylinder pipe to follow the preceding outer cylinder pipe. 10. A step of using the underground excavation device according to claim 6, pulling back the inner pipe and the operating pipe having the cutting bit in the opposite direction to the propulsion direction, removing them from the propulsion pipe, replacing the cutting bits, and then reinserting them into the propulsion pipe. The method for replacing an existing pipeline according to claim 1, comprising: