JPH06193385A - Intermediate pusher for long-distance propulsion - Google Patents

Abstract

PURPOSE:To follow up an intermediate pusher to a front buried pipe even in a curved propelling section by a method wherein a driving force at the time of the shrinkage of an intermediate pushing jack is transmitted over an external cylinder from an internal cylinder and is not worked to a jack and the length of the intermediate pusher is set in approximately the same length as the pipe length of the buried pipe. CONSTITUTION:A ring-shaped first abutting ring 5 is installed in front of an external cylinder 2 having approximately the same diameter as the outside diameter of a buried pipe 11 so as to be abutted against the wall side face of the buried pipe 11. An internal cylinder 3, on which a ring-shaped second abutting ring 4 is mounted similarly, is inserted into the external cylinder 2 at the rear of the external cylinder 2. The length of the internal cylinder 3 is made longer than that of a plurality of intermediate pushing jacks 7 set up into the internal cylinder, and driving force is not worked when the jacks 7 are shrunk. A process, in which the intermediate pushing jack 7 on the leading body side is operated and a rod is elongated and abutted against the first abutting ring 5 and the rear end face of the buried pipe 11 fronter than the intermediate pusher 1 is pushed and propelled and buried successively, is repeated and carried out.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a centering device for a propulsion method for propulsion and burying sewerage, water supply pipes, and gas and electric conduit pipes in the ground. The present invention relates to a device that disperses the propulsive force concentrated on the rear end.

[0002]

2. Description of the Related Art In the propulsion method, the propulsive force for laying the front conductor and the buried pipe is concentrated on the rearmost end face of the buried pipe, so that the propulsive force gradually increases in proportion to the distance as the propulsion extension increases. . If the propulsive force becomes larger than the load bearing capacity of the buried pipe in the axial direction, it will not be possible to carry out propulsion construction using only the former pushing device.Therefore, install a middle pushing device equipped with multiple jacks at the predetermined position of the buried pipe connecting part. A method of distributing the propulsion force of the original pushing device is adopted.

A commonly used mechanism is a mechanism in which intermediate push jacks are arranged on both end wall surfaces of the buried pipe connecting portion and the thrust of the buried pipe in front of the intermediate push device is shared by the intermediate push device. . The outer circumference of the middle push jack is fitted with both buried pipes by providing an annular outer cylinder so that earth and sand and groundwater do not flow into the pipe. The length of the ring-shaped middle press outer cylinder is determined by the stroke length of the middle press jack installed in the middle press device, but if a large stroke length is taken, the middle press outer cylinder length will increase in proportion to that, and Along with this, it becomes necessary to increase the length of the starting shaft. Therefore, as the stroke length, an intermediate press jack of 300 mm to 400 mm is usually used, and the length of the intermediate press outer cylinder is determined.

Since the number of intermediate pushers installed varies depending on the propulsion distance, soil conditions, construction conditions, buried pipe diameter, etc., each condition is examined before construction to calculate the estimated propulsion force. When the propulsive force exceeds the axial load bearing capacity of the buried pipe, an intermediate pushing device commensurate with the propulsive force is appropriately installed to measure the dispersion of the propulsive force.

In the case of the propulsion construction method equipped with the intermediate pushing device, the propulsion burying is performed by the original pushing jack installed in the starting shaft until the load is within the axial load bearing capacity of the burial pipe. When the propulsive force approaches the axial load bearing capacity of the buried pipe, first, the intermediate push jack equipped in the intermediate push device is extended to propulsively bury the front conductor and the buried pipe in front of the intermediate push device. When the extension of the intermediate push jack is completed, the intermediate push jack is switched to the return side, and the original push jack of the original push device is extended by the stroke of the intermediate push jack, and the buried pipe behind the intermediate push device is propulsively embedded. In this way, the thrust of the intermediate press jack is repeated for each stroke, and the buried pipe is propelled.

When the propulsion is completed, the intermediate pushing device is removed. As for the removal method, the intermediate press jack is sandwiched between the front and rear buried pipes, so the jack should be slightly stretched and then contracted to remove it without being pinched. When the removal of the jack is completed, the original push jack is extended and the buried pipe end surface from which the intermediate push jack has been removed is joined and removed.

[0007]

The above-mentioned prior art has enabled the long-distance propulsion construction, but has the following problems. When the propulsion extension is further increased, the number of installation positions of the intermediate pushing device becomes very large from several places to several tens of places. Since the jack must be extended and retracted several times sequentially from the device, the propulsion work becomes very complicated and the propulsion speed is delayed.

Further, in the case of a short stroke middle press jack, the number of times of repeated expansion and contraction of the jack is very large, and the waterproof rubber or the like provided between the buried pipe and the middle push outer cylinder that follow are worn or damaged. There is no water stoppage, and groundwater and sediment have flowed into the pipe.

In long-distance propulsion, the propulsion section often includes curved propulsion. In the curved section, the intermediate push jack is apt to receive an eccentric load due to the propulsive force, which causes a failure due to deformation of the jack or the like and the replacement of the jack. The current situation is that a lot of time is wasted and repairs are very expensive.

In view of the above-mentioned problems of the conventional technology, the present invention provides an intermediate pushing device which can efficiently and reliably perform propulsion embedding even in long-distance propulsion.

[0011]

According to the present invention, a ring-shaped first abutment wheel is mounted on the front surface, an outer cylinder having substantially the same diameter as the outer diameter of the buried pipe, and a ring-shaped thrust plate mounted on the front side, An inner cylinder installed so that the ring-shaped second abutment wheel is fitted into the outer cylinder, a plurality of jacks mounted inside the inner cylinder, and an inner cylinder length longer than the jack length It is an intermediate pushing device for long-distance propulsion characterized by the above.

The outer cylinder and the inner cylinder are fitted to each other so that the gap between the outer cylinder and the inner cylinder is as small as possible in order to improve the waterproofness. If the inner side of the outer cylinder and the outer side of the inner cylinder are machined to be manufactured, more accurate fitting is possible, and the waterproofness is perfect.

The length of the inner cylinder is made longer than the length of the intermediate push jack installed in the inner cylinder, and the propulsive force is applied to the first wheel of the outer cylinder through the front thrust plate through the reinforcing material installed inside the inner cylinder. Transmitted. At this time, the intermediate push jack is structured so as not to contact the first contact wheel of the outer cylinder.

Further, since the structure of the intermediate pressing device is such that the inner cylinder and the outer cylinder are fitted together, the length of the entire device is mainly determined by the length of the intermediate pressing jack. Stroke length is 1m even if it is set to the same length as one buried pipe considering the curve propulsion.
It is possible to adopt the front and rear ones.

[0015]

With the fitting structure of the outer cylinder and the inner cylinder, there is no gap between the outer cylinder and the inner cylinder even when the middle pressing jack is extended, and no groundwater or sediment flows from the middle pressing device section. In addition, since the stroke length of the intermediate pressing jack can be increased, the number of times of jack expansion and contraction can be significantly reduced, so that the propulsion work can be efficiently performed. Propulsion force is transmitted from the inner cylinder to the outer cylinder when the intermediate push jack is reduced, and the thrust does not act on the intermediate push jack. Since the length of the intermediate pusher is set to be approximately the same as one pipe length of the buried pipe, and the structure is such that the intermediate push jack does not bend, the device can be embedded in front even in the curved propulsion section. Easy to follow the tube. When the intermediate push jack is not operated even in the curved propulsion section, the propulsive force does not act on the jack, so that it does not receive an eccentric load.

[0016]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The details of the present invention will be described below with reference to the drawings. FIG. 1 is a vertical sectional view showing an intermediate pressing device 1 according to an embodiment of the present invention. Outer cylinder 2 having the same diameter as the outer diameter of the buried pipe 11
A ring-shaped first abutment wheel 5 is attached to the front of the above so as to abut the wall end surface of the front buried pipe 11. Then, a ring-shaped thrust plate 6 provided so as to come into contact with the first abutment wheel is attached to the front side, and a ring-shaped second abutment wheel 4 is attached to the rear side so as to abut the end surface of the rear buried pipe 11 inside. The cylinder 3 is installed by being fitted into the outer cylinder 2. Inside the inner cylinder 3, a plurality of middle push jacks 7 are evenly mounted in the circumferential direction. The length of the inner cylinder 3 is configured to be longer than the length of the intermediate pressing jack 7 mounted in the inner cylinder 3, and a structure in which a propulsive force does not act when the jack 7 is contracted.

FIG. 2 is a view taken along the line AA in FIG. The thrust plate 6 of the middle push jack 7 has a notch so that the jack head directly contacts the first hitting wheel 5. In the circumferential direction of the inner cylinder 3, a reinforcing member 9 is provided up to the back surface of the thrust plate 6 so that the propulsive force can be reliably transmitted to the front first front wheel 5.

FIG. 3 is a longitudinal sectional view showing in detail the installation condition of the intermediate pressing device 1 of the present invention. The outer cylinder 2 and the inner cylinder 3 have a structure in which the gaps between the outer cylinder 2 and the inner cylinder 3 are in close contact with each other in order to improve the water blocking property. If the inner peripheral surface of the outer cylinder 2 and the outer peripheral surface of the inner cylinder 3 are machined, the fitting accuracy will be further improved and the waterproofness will be perfect. A sealing material 10 is provided at the rear end of the outer cylinder to improve the water blocking property. At this point, the intermediate push jack 7 is in a contracted state, and
Not in contact with the wheel 5

FIG. 4 is a vertical sectional view showing an operating condition of the intermediate push jack 7. The intermediate push jack 7 operates, the rod is extended and abuts against the first hitting wheel 5, and the embedded pipe 11 in front of the intermediate push device 1 is propelled. The device of the present invention is configured as described above.

Here, a construction method using this embodiment will be described. Initially, in the propulsion construction, the rear end surface of the buried pipe 11 is pressed by a former pushing device (not shown) installed in the starting shaft to sequentially embed the buried pipe 11. At the position of the buried pipe 11 where a propulsive force that is slightly less than the axial load bearing capacity of the buried pipe 11,
The first middle press device 1 is installed. After that, when the propulsive force of the buried pipe 11 rearward of the intermediate pushing device 1 approaches the allowable axial load bearing force, the second and third intermediate pushing devices are sequentially installed. As a work procedure using the intermediate pressing device 1, first, the jack 7 of the first intermediate pressing device 1 on the side of the front conductor is activated to extend the front conductor and the buried pipe 11 in front of the first intermediate pressing device 1. Promote buried. Next, when the extension of the jack 7 of the first intermediate press device 1 is completed, the jack 7 of the second intermediate press device 1 is extended, and a buried pipe from the rear of the first intermediate press device 1 to the front of the second intermediate press device 1 is reached. 11
Will be promoted and buried. In this way, the middle pusher 1
Then, the former pushing device is finally operated so that the embedding pipe 11 from the rear of the final intermediate pushing device 1 to the former pushing device is driven and buried. By repeating this operation, the buried pipe 11 is propelled.

An intermediate push jack 7 mounted on the intermediate push device 1.
Since the structure of the outer cylinder 2 and the inner cylinder 3 is a mating structure, the length of the jack 7 can be made large, and the length is substantially the same as the length of the buried pipe 11 and more than twice as long as the conventional one. It can be That is, the stroke length can be doubled or more.

When the propulsion work is completed, the intermediate push jacks 7 mounted on each intermediate push device 1 are removed, and a concrete segment 12 is assembled to the intermediate push jacks 7 as shown in FIGS. Cement milk 13 or the like is injected into the gap between the inner cylinder 3 and the inner cylinder 3 to finish the intermediate pressing device 1 part in the same structure as the buried pipe. In the present embodiment, the method of constructing the wall surface by the concrete segment is illustrated, but the method of injecting the cement milk 13 or the like using a steel form or another conventional technique can be adopted for the construction.

[0023]

As described above, the fitting structure of the intermediate pushing device of the present invention makes it possible to completely prevent the inflow of groundwater or earth and sand from the intermediate pushing device portion, and thus the subsidence pollution of the upper ground of the buried pipe and the intermediate pushing device portion. It is possible to prevent problems such as propulsion work that may occur due to the inclusion of dirt and sand into the ground. In addition, since the structure is such that the propulsive force does not act on the main body of the jack when the intermediate push jack is not in operation, there is no failure due to an eccentric load on the jack, and there is no waste of replacement time during construction or repair costs. Became. In addition, it is possible to use a jack with a longer stroke than before, improving the propulsion speed and propulsion work.

[0024]

[Brief description of drawings]

FIG. 1 is a vertical cross-sectional view showing a long distance intermediate pressing device of the present invention.

FIG. 2 is a view on arrow AA in FIG.

FIG. 3 is a vertical cross-sectional view showing in detail the middle press device of the present invention.

FIG. 4 is a vertical sectional view showing an operating state of the intermediate pressing device.

FIG. 5 is a vertical cross-sectional view showing an assembled state of segments.

FIG. 6 is a cross-sectional view showing an assembled state of segments.

[Explanation of symbols]

 1 Middle push device 2 Outer cylinder 3 Inner cylinder 4 Second abutment wheel 5 First abutment wheel 6 Thrust plate 7 Middle push jack 8 Jack mounting tool 9 Reinforcement material 10 Sealing material 11 Buried pipe 12 Concrete segment 13 Cement milk

Claims (1)

[Claims] 1. A centering device for mounting a plurality of jacks at a predetermined connection portion of a buried pipe to be propulsively buried in a propulsion method to measure the dispersion of the propulsive force applied to the buried pipe. And a ring-shaped thrust plate at the front and a ring-shaped second tube at the rear.
An inner cylinder installed so as to be fitted with the wheel into the outer cylinder, a plurality of jacks provided inside the inner cylinder, and the length of the inner cylinder is longer than the jack length. An intermediate pushing device for long-distance propulsion.