WO1991015657A1

WO1991015657A1 - Injection drilling anchor

Info

Publication number: WO1991015657A1
Application number: PCT/EP1991/000692
Authority: WO
Inventors: Archibald Richter; Hans Mehesch
Original assignee: Bergwerksverband Gmbh
Priority date: 1990-04-11
Filing date: 1991-04-10
Publication date: 1991-10-17
Also published as: DE59102272D1; EP0524223A1; PL168194B1; EP0524223B1; DE9004177U1

Abstract

Composite anchor pipes for stabilising headings and spaces by the injection of e.g. synthetic resin, especially in mining and tunnelling, consist of at least two sections which can be secured together by sleeves and are fitted with a drilling cone and rinsing and injection apertures at the deepest end of the drilling. The anchor pipes have a drilling closure and a releasable connector at the end projecting from the drilling. For the use of such anchor pipes simultaneously as drilling rods and anchors, the section (3) in the form of a drill, which is fitted with a connector designed as a drill adapter (12) is interchangeable with a section (13) designed as an anchor pipe (1), said section (13) being fitted with a bore-hole closure (14) and a non-return valve (19).

Description

Injection drill anchor

The invention relates to an injection drill anchor for securing lines and spaces by injection of, for example, synthetic resin, in particular in mining and tunnel construction, which consists of an anchor pipe which can be assembled from at least two sections which can be connected to one another via sleeves and which is connected to the anchor directed deepest to the borehole ¬ tip has a drill bit, as well as flushing * and injection openings and which is provided with a borehole closure and at the end protruding from the borehole with a detachable connecting element.

It has been known for a long time, in particular in underground mining, in order to maintain the mountains in its association for securing the section cavity, to support the sections by anchoring. For this purpose, adhesive cartridges are usually inserted into a borehole, which are subsequently destroyed by screwing in the anchor rod and by mixing two components, the anchor rod Glue the entire length in the borehole. Problems occur when such anchoring is carried out when the mountains have already been loosened and it is no longer possible to produce boreholes or the subsequent insertion of adhesive cartridges and anchor rods into the deepest borehole.

Such difficulties are avoided by using drill anchors. Drill anchors consist of an anchor tube, at the tip of which a welded or attachable, so-called lost drill bit is attached. The anchor pipe is initially used as a drill pipe and subsequently as an anchor, the anchor pipe being filled after drilling, for example with adhesive mortar, in order to fill the annular space and the upcoming gaps in the mountains. A particular advantage of using drill anchors of this type is that the anchor tubes can be made from sections that can be assembled via sleeves and are thus suitable for being introduced from narrow distances. The drill anchors are introduced using rotary or impact drills. A particular disadvantage when using drill anchors with lost drill bits is the difficulty in adequately sealing the borehole, in particular when injecting a two-component synthetic resin, with correspondingly high pressures.

For the injection of cement mortar screw-on screw caps are used, which are suitable for the intended pressures at the Injecting foaming synthetic resins are completely unsuitable.

According to DE-G 89 06 126, an injection tube is also known which is suitable for bonding loosened mountain areas by injections with strengthening agents, in particular in the face, at face edges and geological disturbances. To seal the borehole, borehole closures in the form of so-called inflatable packers are applied to the injection pipe. Due to the arrangement of corresponding check valves, the inflation packer is inflated to such an extent by the injection pressure that there is a tight contact with the borehole wall so that the actual injection process can then be carried out.

Based on the described prior art, the invention has for its object to provide an injection drill anchor, which is suitable to be used when equipped with a lost drill bit and extendable over corresponding sections both as a drill pipe and as an anchor tube, using rotation - and impact drills avoid the difficulties of inserting anchor rods, especially in common mountains, and which allows the use of synthetic resins that can be pressed in under high pressures, thereby making it possible to completely seal the borehole.

This object is achieved in that the section designed as a drill with a connecting element designed as a drilling adapter is interchangeable with a section designed as an anchor tube, the section being provided with a borehole closure.

For the use of the injection drill anchors, it goes without saying that, following the injection which has been carried out, a spherical cap plate is screwed onto the anchor end using a screw nut which forms a corresponding abutment.

The injection drill anchor can be adjusted to any desired length via several sections and corresponding socket connections, a check valve in the form of a rupture disk being provided in the connection socket of the last section, which has a bochloch closure in the form of an inflatable packer. For this purpose, stops are provided within the internally threaded sleeves, which are designed in connection with a screw-in end of a section for locking the rupture disk. The interchangeable anchor tube section, which receives the inflatable packer, can be replaced at the end with a thread for receiving an injection head or for receiving a dome nut for the dome plate.

In addition, a further check valve is incorporated in the threaded end. The inflatable packer is known as an inflatable hose section surrounding the anchor tube section and held at the ends by bindings is formed, a non-return valve being integrated between the anchor rod and blowing space to prevent the return from the blowing space.

The advantage of the injection drill anchor according to the invention is to be seen in particular in the fact that, when the borehole is produced by the function of the anchor rod as a drill, the drilling cuttings are adequately transported by flushing with water or air, and that the subsequent drilling Function of the same rod as an anchor ensures that the destruction of the borehole produced by pulling out the entire rod or by broken mineral or rock is avoided. The interchangeability of the last section of the whole is designed as a drill or as an anchor Rods also ensure that the borehole in question is completely and securely sealed while saving injection material.

An exemplary embodiment of the invention is shown in the drawings and is explained in more detail below.

Show it:

Figure. 1 - a schematic representation of an exemplary embodiment of an injection drill anchor as it is designed according to the invention for drilling a borehole, and FIG. 2 shows a likewise schematic and sectional representation of an exemplary embodiment of an injection drill anchor as it is designed for the subsequent injection and anchoring, including a borehole closure.

The injection drill anchor according to the exemplary embodiment, as described in FIG. 1, essentially consists of an anchor tube 1, which is composed of sections 2 and 3 via a sleeve 7. At the end facing the deepest of the borehole, section 2 is provided with a lost drill bit 4 ^* and also has flushing or injection openings 5 and 6. Sections 2 can be smooth-walled or profiled for later better adhesion. The sleeve 7 is provided with internal threads 8 and has stops 9 between the ends of the sections 2 and 3. The section 3 is provided at the end protruding from the borehole mouth with a schematically illustrated drilling adapter 12 which can be screwed onto the thread 11. With this design or divided into further sections, the anchor tube 1 is initially used to create a borehole.

FIG. 2 shows an embodiment of an injection drill anchor in which section 3, which is initially required to produce a borehole, is replaced by a section 13. The section 13 is threaded at the end protruding from the borehole provided for receiving an injection head and has a check valve 19. Section 13 is also provided with a so-called inflatable packer 14 for sealing off the borehole. The inflatable packer 14 essentially consists of a hose section 21 which is fixed immovably on the section 13 by means of covers 17, 18. For filling the blowing space of the hose section 21, bores 15 are provided in the section 13, which are sealed by a sleeve 16 and are designed as a check valve. At the front end of section 13, namely within the sleeve 7, a rupture disk 10 is inserted, which is locked in position between a stop 9 and the end of a section 2 or 13. The openings provided as flushing openings 5, 6 in the production of the borehole now serve as injection openings.

When an injection drill anchor is introduced, the inner channel of the anchor tube 1 initially serves as a flushing channel when a drill hole is made in the rock, in order to use the flushing medium to remove the cuttings from the drill hole via the annular space.

After drilling in the anchor pipe 1, which can be assembled from several sections 2, it is only pulled out of the borehole to the extent that the last section 3 is released from the socket connection and replaced with a section 13 which is equipped with an inflatable packer 14 and the connection for an injection head .

When performing the injection, first of all through the bursting disk 10 serving as a check valve, the inflation space of the inflatable packer 14 is inflated in such a way that a tight, all-round contact with the borehole wall is achieved. The further increasing pressure of the injection destroys the rupture disk 10 and the annular space or the fissures in the mountains are injected. After the end of the injection, a spherical cap plate is screwed onto the end of the anchor tube protruding from the mouth of the borehole.

1 anchor tube

2 section

3 section

4 core bits

5, 6 rinsing or injection openings

7 sleeve

8 internal threads

9 stop

10 rupture disc

11 threads

12 drilling adapters

13 section

14 inflatable packers

15 holes

16 cuffs 17, 18 cover

19 check valve

20 threads

21 hose section

Claims

Protection claims

1. Injection drill anchors for securing routes and spaces by injection of, for example, synthetic resin, in particular in mining and tunnel construction, which consists of an anchor pipe which can be assembled from at least two sections which can be connected to one another by sleeves and which has a drill bit at the anchor tip which is the deepest in the borehole , and has flushing and injection openings and which is provided with a borehole closure and at the end protruding from the borehole with a releasable connecting element, characterized in that the section (3) designed as a drill, which has a Drilling adapter (12) trained connection element is provided, can be exchanged for a section (13) designed as an anchor tube (1), the section (13) being provided with a boring hole closure and a check valve.

2. Injection drill anchor according to claim 1, characterized in that the check valve is designed as a bursting disc (10).

3. injection drill anchor according to claim 1, characterized ge indicates that the BohrlochverSchluß is designed as a inflatable packer (14).

4. injection drill anchor according to claim 1, characterized ge indicates that the section (13) is provided at both ends with check valves (10, 18).

5. injection drill anchor according to claim 4, characterized ge indicates that the check valve (10) is designed as a rupture disc.

6. injection drill anchor according to claim 1, characterized ge indicates that the sections (2, 3; 2, 13) connecting sleeve (7) with a the ends of the sections (2, 3; 2, 13) receiving stop (9th ) is provided and that the stop (9) is designed for locking a check valve (10).