JPS5931639B2 - Intermediate sleeve in propulsion method - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an intermediate sleeve in a propulsion method.

In a propulsion method in which a buried pipe is formed by pressing the rear end of the pipe with a hydraulic jack and pushing the pipe into the ground, an extensible intermediate sleeve is inserted in the middle of the pushed underground pipe, and the pipe is There is a system in which the buried conduit is successively propelled in a lengthwise manner by alternately expanding and contracting a booster jack that presses the rear end and an intermediate pusher jack that expands and contracts the intermediate sleeve.

That is, in Figs. 1 and 2, 1 is the propellant, 2
is the reaching hole, and the pipe 3 is inserted into the side hole drilled on the side of the propellant 1.
is inserted, and the rear end of the pipe 3 is pushed by the pusher jack 4 to push it into the soil and propel it, and the washing from the leading pipe face is discharged from the rear end of the pipe 3 into the propeller 1 and out of the pipe. As the tube 3 moves forward, new tubes 3 are sequentially added behind it (.

When the buried conduit 5a reaches a certain length, the intermediate sleeve 6 is inserted and the pipe 3 is added again behind it to form the buried conduit 5b.

The intermediate sleeve 6, as shown in FIG. 8 The distal end side of the main pipe 9 is fitted onto the outer periphery of the intermediate part so as to be relatively slidable in the pipe axial direction to form a telescopic sliding part. Projected jack mounting protrusion 1
It is interposed between 1 and 1.

After inserting the intermediate sleeve 6, the tube 3 is propelled as follows.

That is, from the extended state of the pusher jack 4 shown in FIG. After adding a spacer or the next pipe 2 between the rear end and the booster jack 4 and returning the middle pusher jack 7 to its original state (retracted stroke), extend the booster jack 4 to move the rearward direction. The buried pipeline 5b is advanced to the state shown in Fig. 1, and this operation is repeated thereafter to create the buried pipelines 5a and 5b.
The underground pipeline is formed by moving the pipes in a lengthwise manner.

According to the Kono construction method, the front and rear buried pipes 5a and 5b are propelled separately with the intermediate sleeve 6 as the boundary, so the thrust required for propulsion is small, and the distance between the propulsion shaft 1 and the reaching shaft 2 is long. Even in such a case, it is possible to easily propulsion and bury the pipe 3 and its joints without causing any strength problems.

In such a construction method, the intermediate sleeve 6 is left as it is in the pipe line after completion of piping, and forms a part of the pipe line.

However, when an earthquake-resistant structure or the like is adopted for the conduit, even if the joint portion of each pipe is constructed to prevent separation, the conventional intermediate sleeve 6 has a problem in that the main pipe 9 and the extension pipe 8 separate from each other.

The present invention proposes an intermediate sleeve that can prevent the main pipe and the telescopic pipe from separating from each other after piping work is completed, and the work is not hindered by the separation preventing means during propulsion.

An embodiment of the present invention will be described below based on the drawings.

FIG. 3 is an enlarged view of the main part of FIG. 2, and shows the extension pipe 8 of the main pipe 9.
An annular recess 12 is formed on the inner surface of the fitting portion with the
A stepped portion 12a is formed on one side thereof.

Reference numeral 13 designates a lock ring that engages with the stepped portion 12a, and is fitted into an annular groove 14 provided on the outer surface of the extension tube 8.

The rock song 13 is divided into sections in the circumferential direction and has a biasing force for diameter reduction.

The annular groove 14 has a depth capable of accommodating the entire rock song 13.

A plurality of screw holes 15 penetrating from the inner surface of the extension tube 8 are provided at appropriate intervals in the circumferential direction on the bottom surface of the annular groove 14, and a set bolt 16 for supporting the lock song 13 with an expanded diameter is screwed into each screw hole 15. has been done.

A seal bolt 17 is screwed into the screw hole 15, and a rubber seal ring 25 is interposed between its head and the opening periphery of the screw hole 15.

A fitting groove is provided on the inner surface of the main pipe 9 on the distal side of the recess 12, and a rubber annular sealing member 18 is fitted therein.

19 is a sediment inflow prevention plate that covers the outer surface of the tip of the main pipe 9;
One end is bolted to the flange 20 of the extension pipe 8.

A sealing material 26 is fitted into an annular groove on the outer surface of the main pipe 9, and is in contact with the inner surface of the earth and sand inflow plate.

The earth and sand inflow prevention plate 19 prevents earth and sand from entering the sliding contact surface between the main pipe 9 and the extension pipe 8.

A hole 21 is provided in the extension pipe 8 corresponding to the one end of the earth and sand inflow prevention plate 19, and a device for feeding a lubricant into the earth and sand inflow prevention plate 19 is connected to the hole 21.

With this configuration, the set bolt 16 and seal bolt 17 are removed from the threaded hole 15 during piping work such as during propulsion, and the lock ring 13 contracts in diameter due to its diameter reduction biasing force and is inserted into the annular groove 14. be accommodated.

Therefore, the lock ring 13 does not get in the way (the intermediate sleeve 6 can be expanded and contracted).

Note that the rock song 13 does not necessarily have to have a diameter reduction biasing force.

When the piping work is completed, the set bolt 16 is screwed in from the inner surface of the telescopic tube 8 to expand the diameter of the lock ring 13, and the seal bolt 1 is screwed in.

This allows the lock ring 13 and the stepped portion 12a of the main pipe 9 to engage with each other, and this engagement prevents the main pipe 9 and the extension pipe 8 from separating from each other.

As explained above, according to the present invention, a circumferentially split lock ring that can be engaged with a stepped portion on the inner surface of the main pipe is fitted into an annular groove on the outer surface of the extension pipe, and the annular groove covers the entire lock ring. The depth is set to accommodate the diameter of the lock ring, and the diameter of the lock ring is expanded and held using a set bolt, so it is possible to prevent the main pipe and the extruded pipe from separating from each other after the piping is completed, without hindering elasticity during propulsion. can.

[Brief explanation of the drawing]

The drawings show one embodiment of the present invention, and FIG. 1 is a schematic diagram of a conduit using an intermediate sleeve, FIG. 2 is a partially cutaway front view of the intermediate sleeve, and FIG. 3 is a partially enlarged sectional view of the intermediate sleeve. be. 6...Intermediate sleeve, T...Inner push jack, 8...Extension pipe, 9...Main pipe,
12... Concavity, 12a... Step, 13
・・・・・・Lock ring, 14・・・Annular groove,
15...Screw hole, 16...Curved set bolt, 1
7...Seal bolt, 18...Seal material.

Claims (1)

[Claims] 1. An extension pipe protruding from one end is slidably fitted into the main pipe, and a step is provided on the inner surface of the main pipe at the fitting part with the extension pipe,
It fits into an annular groove provided on the outer surface of a circumferentially split lock ring extending tube that can be held in place with this stepped part, and the annular groove has a depth that can accommodate almost the entire lock ring, allowing it to expand and contract. An intermediate sleeve in a propulsion method, characterized in that a set bolt that contacts the inner surface of a lock ring is screwed into a screw hole that penetrates from the inner surface of the pipe to the bottom surface of the annular groove.