JPH0639876B2 - Middle push propulsion structure - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION <Industrial field of application> The present invention is provided for giving thrust to a preceding propulsion pipe in a propulsion method of laying a pipe (usually a Huym pipe) in soil. This is related to the middle push propulsion structure such as the middle push jack and the middle push propulsion pipe.

<Prior Art> A conventional push-push structure has a structure as shown in FIGS.

The middle push propulsion pipe 1 has a long front step portion 2 having a small diameter on the front end side at the front end, and a short rear step portion 3 having a small diameter on the front end side at the rear end. The reason why the length of the front step portion 2 is long is to prevent the intermediate push propulsion tube 1 from interfering with the rear end of the intermediate push collar 9 which will be described later, when the intermediate push jack 7 to be described later is removed.

A standard propulsion pipe 4 having stepped portions 5 and 6 having small diameters at both front and rear ends is disposed in front of and behind the intermediate push propulsion pipe 1, and the central push propulsion pipe 1 and the front standard propulsion pipe are provided. Four
A plurality of intermediate push jacks 7 are arranged between A and A, with a corresponding wheel 8 interposed therebetween.

Further, on the outer peripheral surfaces of the front step portion 2 of the middle push propulsion pipe and the rear step portion 6 of the front standard propulsion pipe 4A around the middle push jack 7, rubber-made members fixed to the step portions 2 and 6, respectively. A cylindrical intermediate press collar 9 made of steel is disposed with a packing 11 interposed. The middle push collar 9 is provided with a flange portion 10 that extends radially inward on the inner peripheral surface on the front side, and the flange portion 10 is arranged between the front standard propulsion pipe 4A and the center push jack wheel 8. ing.

In addition, the rear step portion 3 of the middle push propulsion pipe and the rear standard propulsion pipe 4B
The outer peripheral surface of the front step portion 5 of the
A standard collar 12 made of steel and having a cylindrical shape is disposed with a packing 11 fixed thereto. This standard color 1
2 is provided with a flange portion 13 that extends in the radial direction on the inner peripheral surface of the front-rear direction intermediate portion, and the flange portion 13 is arranged between the intermediate push propulsion pipe 1 and the rear standard propulsion pipe 4B. In addition, the standard collar 12 and the packing 11 are also arranged at the connecting portions between the standard propulsion pipes 4 before and after the front standard propulsion pipe 4A and the rear standard propulsion pipe 4B.

In this intermediate push propulsion structure, the standard push pipes 4A and 4F in front of the intermediate push propulsion pipe 1 are extended by the extension of the intermediate push jack 7.
And so on (see Fig. 3).

<Problems to be Solved by the Invention> However, in the conventional intermediate push propulsion structure, when the intermediate push jack 7 extends, the intermediate push collar 9 moves forward with respect to the intermediate push propulsion pipe 1 and moves in front of the intermediate push propulsion pipe. Since the sliding part 11 slides on the packing 11 of the stepped part 2, the packing 11 may be dropped or worn, and the surrounding sand and sand from the space between the intermediate pushing collar 9 and the front stepping portion 2 of the intermediate pushing propulsion pipe. Water sometimes leaked. By the way, even when the packing 11 is not significantly worn, even when the surrounding groundwater pressure is high or the injection pressure of the lubricant / backfill is high, when the intermediate press jack 7 extends, the intermediate press collar 9 and Sediment and water leaked from between the front step 2.

And in the event of such a leak of sand or water,
There is a risk of causing disasters such as subsidence and depression of the surface.

This invention solves the above-mentioned problem, and when the intermediate push jack extends, it is possible to prevent earth and sand and water from leaking between the intermediate push collar and the intermediate push propulsion pipe. It is intended to provide a structure.

<Means for Solving the Problems> An intermediate pushing propulsion structure according to the present invention includes a long front step portion having a front end side with a small diameter and a short rear step portion having a rear end with a small diameter. Before and after the push propulsion pipe, standard propulsion pipes provided with stepped portions each having a small diameter at the front and rear ends are arranged, and a middle push jack is provided between the mid push propulsion pipe and the front standard propulsion pipe. Disposed on the outer peripheral surface of the front step portion of the middle push propulsion pipe and the rear step portion of the front standard propulsion pipe around the middle push jack,
An intermediate push collar having a flange portion arranged between the front standard propulsion pipe and the intermediate push jack is provided with a packing fixed to each step portion, and a rear step of the intermediate push thrust pipe is provided. Section and a front step portion of the rear standard propulsion pipe are provided with standard collars with interposing packings fixed to the step portions, respectively, and the forward standard propulsion is provided by extension of the intermediate press jack. A middle push propulsion structure in which a pipe advances, wherein wear resistance and stretchability are provided around the middle push propulsion pipe by connecting front and rear ends to the middle push collar and the standard collar behind the middle push collar, respectively. And a tubular waterproof sheet having the above are arranged.

<Operation / Effect of Invention> In the intermediate push propulsion structure according to the present invention, when the intermediate push jack extends and the intermediate push collar moves forward with respect to the intermediate push propulsion pipe,
The cylindrical waterproof sheet, which has both front and rear ends connected to the intermediate press collar and the standard collar behind the intermediate press collar, has abrasion resistance and stretchability, so it can be used to advance the intermediate press collar without damage. Following this, the intermediate push collar and the standard collar behind it will extend while covering the periphery of the intermediate push propulsion pipe.

Therefore, when the Nakashi push jack extends,
Since it is completely covered with the middle push collar, the standard collar behind it, and the waterproof sheet, the middle push collar slides on the packing on the front step of the middle push propulsion pipe, and the packing falls off or wears. Even if it does, it is possible to completely prevent earth and sand and water from leaking between the intermediate push collar and the intermediate push propulsion pipe.

Therefore, in the intermediate push propulsion structure according to the present invention, when the intermediate push jack extends, it is possible to completely prevent earth and sand and water from leaking from between the intermediate push collar and the intermediate push propulsion pipe.

<Embodiment> An embodiment of the present invention will be described below with reference to the drawings.
In the drawings, the same members as those in the related art are designated by the same reference numerals.

As shown in FIG. 1, the middle push propulsion structure of the embodiment has a step portion 5 at both ends before and after a middle push propulsion tube 1 including a front step portion 2 and a rear step portion 3 as in the conventional case. A standard propulsion pipe 4 including a central propulsion pipe 1 and a front standard propulsion pipe 4A is provided.
And a plurality of inner press jacks 7 are disposed with a corresponding wheel 8 interposed therebetween, and an outer peripheral surface of the front step portion 2 of the middle push propulsion pipe and the rear step portion 6 of the front standard propulsion pipe 4A. Further, an intermediate pressing collar 9 is arranged with a packing 11 fixed to the step portions 2 and 6 interposed therebetween. Further, as in the conventional case, the packings 11 fixed to the step portions 3 and 5 are respectively provided on the outer peripheral surfaces of the rear step portion 3 of the middle push propulsion tube and the front step portion 5 of the rear standard propulsion tube 4B. A standard collar 12 is provided. Further, the standard collar 12 and the packing 11 are similarly arranged at the connecting portions of the standard propulsion pipes 4 before and after the front standard propulsion pipe 4A and the rear standard propulsion pipe 4B. A rear shaft (not shown) such as a vertical shaft for introducing the standard propulsion pipe 4 into the horizontal shaft, a former push jack, etc. are disposed behind the rear end of the standard propulsion pipe 4 and the like.

In the middle push propulsion structure of the embodiment, a cylindrical waterproof sheet 15 having front and rear ends connected to the middle push collar 9 and the standard collar 12 behind the middle push thrust pipe 1 is disposed around the middle push thrust tube 1. There is.

This waterproof sheet 15 is provided with annular metal fittings 16 at both ends, and has a reinforced waterproof cloth made of soft vinyl chloride or the like, which has wear resistance to withstand sliding against the natural earth and sand 14 and the medium push propulsion pipe 1, and elasticity. Are formed from. The metal fitting 16 is fixed to the middle press collar 9 and the standard collar 12 so as to be in close contact with each other by using rivets or welding.
It has a good sealing property.

The length of the waterproof sheet 15 when contracted is from the rear portion of the intermediate press collar 9 to the standard collar 1 when the intermediate press jack 7 is contracted.
2 It is almost the same as the distance to the front part.

The arrangement of the waterproof sheet 15 is such that, when the standard propulsion pipe 4A is introduced into the horizontal shaft and the intermediate pressing collar 9 is installed in the rear step portion 6, the front portion of the waterproof sheet 15 is connected to the rear portion of the intermediate pressing collar 9. After that, when the intermediate push propulsion pipe 1 is introduced into the horizontal shaft and the standard collar 12 is arranged, the standard collar 12 is connected to the rear part of the waterproof sheet 15.

When the waterproof sheet 15 is arranged in this way,
When the intermediate push jack 7 extends and the intermediate push collar 9 advances with respect to the intermediate push propulsion tube 1, the waterproof sheet 15 has abrasion resistance and stretchability, so that the intermediate push jack 9 is not damaged. Following the forward movement of the pressing collar 9, the intermediate pressing collar 9 and the standard collar 12 behind the intermediate pressing collar 9 are extended while covering the surroundings of the intermediate pressing propulsion pipe 1.

Therefore, when the intermediate push jack 7 is extended, the area around the intermediate push propulsion pipe 1 is completely covered with the intermediate push collar 9, the standard collar 12 behind the intermediate push collar 9, and the waterproof sheet 15. Even if the packing 11 slips off and wears due to sliding with the packing 11 of the push propulsion pipe front step portion 2,
It is possible to completely prevent earth and sand and water from leaking between the intermediate push collar 9 and the intermediate push propulsion pipe 1.

[Brief description of drawings]

FIG. 1 is a sectional view of an intermediate push propulsion structure showing one embodiment of the present invention, FIG. 2 is a sectional view showing a conventional structure, and FIG. 3 is a structure when a conventional intermediate press jack is extended. FIG. 1 ... Medium push propulsion pipe, 2 ... Front step part, 3 ... Rear step part, 4A / 4B / 4F ... Standard propulsion pipe, 5 ... Front step part, 6 ... Rear step part , 7 ... Nakashiki Jacqui, 9 ... Nakashiki Collar, 10 ... Flange, 11 ... Packing, 12 ... Standard color, 15 ... Waterproof sheet.

Claims (1)

[Claims] 1. A front and rear end of each of the front and rear ends at the front and rear of an intermediate push propulsion pipe provided with a long front step portion having a small diameter on the front end side of the front end and a short rear step portion having a small diameter on the rear end tip side. A standard propulsion pipe having a stepped portion with a small diameter is provided, and an intermediate press jack is provided between the intermediate push propulsion pipe and the front standard propulsion pipe, and the intermediate push jack around the intermediate push jack is provided. On the outer peripheral surface of the front step portion of the propulsion pipe and the rear step portion of the front standard propulsion pipe,
An intermediate push collar having a flange portion arranged between the front standard propulsion pipe and the intermediate push jack is provided with a packing fixed to each step portion, and a rear step of the intermediate push thrust pipe is provided. Section and a front step portion of the rear standard propulsion pipe are provided with standard collars with interposing packings fixed to the step portions, respectively, and the forward standard propulsion is provided by extension of the intermediate press jack. A middle push propulsion structure in which a pipe advances, wherein wear resistance and stretchability are provided around the middle push propulsion pipe by connecting front and rear ends to the middle push collar and the standard collar behind the middle push collar, respectively. An intermediate push propulsion structure, characterized in that a tubular waterproof sheet having is disposed.