JPH06240658A - Lock chamber device - Google Patents

Abstract

PURPOSE: To obtain a lock chamber device which can maintain the pressure in the annular space of a borehole and, in addition, controls the flow velocity of a material leaving the borehole by providing a chamber having at least one orifice, a shut-off valve, and a conduit. CONSTITUTION: A lock chamber device is constituted in such a way that, in the lower section 4a of a chamber 4, a normally opened type shut-off valve 12 and a conduit 13 for removing materials leaving a borehole are provided near the connecting section with the upper section 4b. A valve 14 which is automatically adjusted by a device 15 connected to a pressure probe 16 as the function of the pressure spread in the borehole is connected to the conduit 13 so as to maintain the pressure in the borehole within a prescribed value range and to prevent a dangerous excessively high pressure from being generated in the horehole. The lock chamber device constituted in the above-mentioned way is connected to a pressurized fluid source as necessary when the pressure in the borehole drops from a prescribed value for some reason.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a lock chamber device for a ground handling device with one or more rotary jets.

[0002]

BACKGROUND OF THE INVENTION Methods of treating ground with one or more rotary jets are well known and have been used to produce barrier screens that block permeable ground mass. According to this device, an exogenous substance or slurry is introduced in the form of at least one high-speed jet through the borehole into the soil in question. This high-speed jet is properly directed and destroys the ground properly on its trajectory. And when the above-mentioned ground sets, depending on the nature of the ground, depending on the nature of the ground, the compositional elements of the soil mortar or concrete are mixed with brass and lead compositional elements (for example when the ground is gravel or sand), or just purely. The composition of the slurry or grout is replaced by soil and lead (eg when the ground is clay). The jet operates with a certain radius of gyration depending on the flow velocity, the driving pressure and the characteristics of the ground. If the tool forming the jet is set to rotate slowly in translation inside the borehole, the approximate cylindrical volume of the ground to be treated is the radius as the radius of the jet's rotational motion under the conditions of use. And has a height corresponding to the magnitude of the translational movement.

It is thus understood that this jet technique can result in a blocking screen due to the juxtaposition of multiple cylindrical elements (or cylinders) of the ground. These cylindrical elements (or cylinders) are handled over a certain height, the barrier screens are made using a network of multiple bore holes provided at a certain density, which cylindrical elements or cylinders form a continuous mass. Constitute. It is also possible to use this type of cylindrical element or cylinder as a compression element.

Various types of jets are used. That is, one jet of slurry or a jet of slurry surrounded by an annular jet of air to increase the radius of action, and the separation of water and slurry surrounded by an annular jet of air ensuring ground destruction. With a jet
It usually consists of a combination of jets supplied at a lower level than the jet of water.

To implement this device, one device is used. The apparatus feeds the slurry to one or more pumps for making cement slurry and includes a central unit for making cement slurry. These pumps are connected via rotating seals to a piece of tubing that leads to the borehole where the jet is handled. The one-piece tube is translationally and rotationally driven using a hydraulic rotary head that clamps the upper end of the tube. The tube is mounted in a perforated jar. The pump uses 203.9 for breaking liquid (slurry or water).
4 kg / cm ² (200 bar) to 713.79 kg /
Eject at a pressure of cm ² (700 bar) or less.

The one-piece tubing is formed from a plurality of tubular unit parts which are fitted and connectable to a sealing gasket. Each section may be formed by one tube (one jet) or several coaxial tubes (double or triple jet). The fluid (slurry, water) is ejected from one or more nozzles having a diameter of approximately 2 mm to 4 mm. The tube has a diameter of approximately 50 mm to 200 mm.

Recently, an improvement was proposed in French patent application No. 92 13154, filed on November 3, 1992. The improvement consists of using a flexible pipe outside the one-piece tube to supply the nozzle, where the tube is used only for mechanical drive and no longer continuous but reciprocating rotary motion drive. To be done.

A drilling tool is further mounted below the nozzle at the lower end of the tether tube to create a boring hole to perform the screen formation. The tool may be solid or may consist of the outflow of perforating fluid supplied by a series of tubes. In the latter case, the tool will add a tubular section or be equipped with a non-recoverable device to prevent settling of sediment within the tube during recovery. Alternatively, the drilling may be done in a pre-separated device.

[0009]

In practice, handling of the jet is initiated by the placement of the jet device at the bottom of the boring hole, driving the tube in a translational translational motion toward the tip of the boring hole to achieve the desired height. This is done until a cylinder of the ground with a depth is obtained. Under certain operating conditions,
For example, in an upright boring hole, if the material jetted by the jetting device is trying to exit the boringing hole under gravity, or if the tip of the boringing hole is located at a level lower than the level of groundwater accumulation, the jetting device There are difficulties in implementing. This is because we do not know how to control the flow rate of material exiting the boring hole. Therefore, there is a demand for a device that can solve this problem.

The object of the invention is to be able to maintain the pressure within the annular space of the borehole which exists between the wall of the borehole and the series of tubes, and of the material which necessarily leaves the borehole. An object of the present invention is to provide a device capable of controlling the flow rate.

More particularly, the present invention relates to a device used in connection with a device for handling soil with at least one rotary jet, comprising a series of tubes provided at the base with at least one injection nozzle. , In which the nozzle is supplied with a material which is jetted by means of a continuous tube or a flexible pipe outside this continuous tube, arranged in a boring-hole and detent connection on a continuous surface of the boring-hole A chamber provided with at least one orifice that fits a sealing gasket through which a series of tubes and optionally attached flexible pipes pass; a shut-off valve capable of completely closing a bore hole; Connected to the chamber, excessive pressure is generated in the borehole And adjusting valve for adjusting the flow rate of the material is provided in order to avoid, it is characterized in that it comprises a conduit for removing material exiting from the bore hole.

The control of the regulating valve of the removal conduit depends selectively on the pressure prevailing in the borehole and is automatically carried out by a suitable device. It also allows the chamber to be connected to a pressurized fluid source, if desired, for the purpose of maintaining the pressure in the borehole even when the borehole pressure falls below a predetermined threshold. A tap can be provided on the chamber. Preferably, the chamber is disassembled into at least two parts. A lower part equipped with a shutoff valve,
It is divided into an orifice or an upper part provided with a plurality of orifices.

[0013]

【Example】

Example 1. Hereinafter, the configuration and operation of the device of the present invention will be described in detail with reference to the drawings. FIG. 1 is a schematic diagram of an apparatus according to the present invention. 2 and 3 are schematic views showing the installation of the rotary jet handling device in the device of FIG.
The device of FIG. 1 is provided in a series of boring holes 1, which receives a device for handling the ground with one rotary jet or a plurality of rotary jets.

This device is of the type described in the above mentioned French patent application and represents a flexible pipe as shown by only one stretch of tubes 2 and 3a and 3b for supplying nozzles. ing. The device comprises a chamber 4 provided in the extension of the borehole 1 to form a lock chamber, and a seal 5 to prevent leakage between the base of the chamber and the wall of the borehole. The chamber 4 is made of steel, for example, and comprises a lower portion 4a and an upper portion 4b fixed by, for example, bolts.
The upper portion 4b is provided with orifices 6, 7 and 8 through which the continuous tube 2 and the pipes 3a and 3b pass, and each of the orifices 6, 7 and 8 allows movement and sliding of the tube 2 and the pipes 3a and 3b while preventing leakage. An annular seal 9 for ensuring
10 and 11 are provided.

The lower portion 4a is located near the connection with the upper portion 4b,
A normally-open type shutoff valve 12 and a conduit 13 for removing material coming out of the boring hole are provided.
A valve 14 is provided which is self-regulating as a function of the pressure prevailing in the borehole by a device 15 connected to a pressure probe 16 provided in the chamber. The role of the valve 14 is to keep the pressure in the borehole within a predetermined range and to prevent dangerous overpressure in the borehole.

The device then has a pipeline 17 connected to the chamber and equipped with a valve 18.
If for any reason the borehole pressure drops below a desired value, it can optionally be connected to a source of pressurized fluid.

2 and 3 show a case where the apparatus of FIG. 1 is provided with an apparatus for handling the ground by one or a plurality of rotating jets. After the lower part 4a is fitted into the boring hole 1 and the boring hole is sealed with the seal 5, the shut-off valve 1
2 is closed as shown in FIG. The nozzle head 20 of the rotating jet device is placed on the valve 12,
Then, as shown in FIG. 3, the tube 2 and the flexible pipes 3a, 3b are connected to the head through the orifices 6, 7, 8 in the upper part 4b of the chamber. After that, the device is completed only by fixing the lower portion 4a and the upper portion 4b with bolts. Before lowering the head 20 in the boring hole, the valve 12 is opened. Head 2 from the boring hole
When 0 is removed, the operation opposite to that described above is performed.

If the rotary jet device used has a tube with nozzles at the same time, that is, a convenient rotary jet device without a flexible pipe, a chamber in which only one orifice 6 is provided and the orifices 7 and 8 can be omitted is applied. What you can do is self-evident.

[0019]

As described above, this device can control the flow rate of the material exiting the boring hole under the condition of the work site requiring the boring hole to which the pressure is applied, while controlling the flow rate of one rotating jet or a plurality of jets. It is possible to use a device that handles the ground with a rotating jet.

[Brief description of drawings]

FIG. 1 is a schematic diagram of an apparatus according to the present invention.

2 is a schematic diagram showing the installation of a rotating jet handling device on the device of FIG. 1;

FIG. 3 is a schematic diagram showing the installation of a rotary jet handling device on the device of FIG.

[Explanation of symbols]

 1 boring hole 2 continuous pipe 3a, 3b pipe 4 chamber 4a lower part of chamber 4b upper part of chamber 5 seals 6, 7, 8 orifices 9, 10, 11 annular seal 12 isolation valve 13 conduit 14 valve 16 pressure probe 17 Pipeline 20 nozzle head

 ─────────────────────────────────────────────────── ─── Continued Front Page (72) Inventor Jean-Claude Getey 77680 Roisy Anne Brie, Leu Frederic Chopin 5 (72) Inventor Pierre Crémont France, 92360 Mudon La Foret, Liu Alfred De Musée 4

Claims (4)

[Claims] 1. A lock chamber device for use in connection with a device for handling ground with at least one rotary jet, the lock chamber device comprising a series of tubes provided with at least one injection nozzle at its base. In a lock chamber device in which the nozzle is supplied with material to be injected by means of a continuous tube or a flexible pipe outside this continuous tube, it is connected continuously to the surface of the borehole and is leakproof. A chamber provided with at least one orifice to fit a sealing gasket through which a series of tubes and optionally attached flexible pipes pass, and a shut-off valve capable of completely closing the boring hole. And connected to the above chamber, excessive pressure A lock chamber apparatus comprising: a regulating valve for regulating a flow rate of the material to avoid generation in the boring hole, and a conduit for removing the material exiting the boring hole. 2. The lock chamber device according to claim 1, wherein the control of the adjusting valve is based on the pressure in the boring hole. 3. The lock chamber device according to claim 1, further comprising a tap for connecting the chamber to a pressurized fluid source. 4. The lock chamber apparatus of claim 1, wherein the chamber comprises at least a lower portion provided with the shutoff valve and an upper portion provided with the orifice.
A lock chamber device characterized by being divided into two parts.