CN105909287B - A kind of coal mine fully-mechanized mining working lead abutment pressure area deep hole grouting technique and method - Google Patents

Abstract

The invention provides a technology and method for deep hole grouting in a fully mechanized mining face in an advanced bearing pressure zone. This method solves the problem of high mining height, discharge and grouting by selecting a mine-used early-strength deep-hole grouting material combined with a high-pressure and large-flow grouting pump, and adopts the technology of forming holes in advance, inserting pipes, sealing holes, and grouting in advance supporting pressure areas. This method does not affect the production of the coal face, which is often encountered in high-yield and high-efficiency coal mining faces such as top coal, and improves the mechanical properties of the coal body in essence, reshaping the integrity of the coal body, and has a good promotion sex.

Description

A technology and method of deep hole grouting in the advanced bearing pressure zone of fully mechanized coal mining face

technical field

The invention relates to the field of prevention and control of coal wall slabs in a fully mechanized mining face, in particular to a technique and method for deep hole grouting in an advanced support pressure zone of a fully mechanized mining face.

Background technique

At present, the coal industry is developing towards high-yield and efficient large-scale mechanization. Due to the outstanding advantages of high-yield and high-efficiency, the large-scale and high-mining coal mining method has been applied in many mining areas in my country; It can reach more than 10 meters a day and its mining height is relatively large, generally greater than 6m. During the mining process, especially in the final mining stage, the coal wall of the working face is prone to flaking. After flaking, it will seriously affect the production safety of the working face and delay production progress.

The current way to prevent and control the coal wall of the working face is generally to improve the support equipment or the coal wall grouting of the working face; for the former, because the mechanical properties of the coal cannot be fundamentally improved, it is often not obtained in some soft coal mining areas. Good anti-slab effect; for the latter, because the direct grouting operation on the coal wall of the working face will greatly interfere with the normal production of the working face, it is rarely used; When the drilling operation cannot keep up with the production progress, or the grouting timing is unreasonable, and the coal body cracks have not yet developed, the grout cannot be injected; due to the high-yield and high-efficiency coal mining face, the advancing speed is fast, if The selected grouting material is unreasonable, and the strength of the grout stone body may not keep up with the advancing speed of the working face; therefore, according to the time-space transformation relationship of the high-yield and high-efficiency coal mining face and the evolution law of surrounding rock fissures, A mine-used early-strength deep-hole grouting material is selected, and a method of forming holes in advance and deep-hole grouting in the advanced supporting pressure zone of the working face is proposed.

Contents of the invention

The technical problem to be solved by the present invention is to solve the problem that it is difficult to effectively deal with the side panels often encountered in the production of fully-mechanized mining working faces, especially working faces with large mining heights. with method.

Technical scheme of the present invention is realized like this:

A technology and method for deep hole grouting in an advanced bearing pressure zone of a fully-mechanized coal mining face, the steps of which include: four technological processes of forming holes in advance, inserting pipes, sealing holes, and grouting in an advanced bearing pressure zone;

(1) Drilling in advance: the advanced coal mining face (1) ≥ 200m, along the working face transport level roadway (2), return air level roadway (3) or main withdrawal roadway (5) for drilling operations, drilled in advance The grouting hole (4), the drilling depth covers the entire length of the advanced coal mining face;

(2) Intubation process: Insert the seamless steel pipe (9) within the range of 10m-20m from the hole opening in the shallow part of the drilled hole, and insert the PE pipe (7) in the deep part of the drilled hole until the bottom of the hole;

(3) Hole sealing process: First, insert a piece of aluminum-plastic pipe (10) with a length of 10m to 20m into the drilled hole and stuff cotton yarn (8) into the hole to seal the drilled hole; then, insert the aluminum-plastic pipe (10) Connect with the double-liquid grouting system; finally, use the double-liquid grouting material to seal the hole, and slowly pull out the aluminum-plastic pipe (10) from the inside out during the sealing process.

In the grouting process in the advanced bearing pressure zone, the timing of grouting is selected when the range of influence of the advanced bearing pressure on the working face covers the drilling area. Generally, the advanced coal mining working face is 15m to 30m. At this time, two sets of grouting equipment are used on both sides of the working face Parallel operation in level road or main withdrawal roadway.

In the grouting process in the advanced support pressure zone, single-liquid grouting equipment and materials are used.

The boreholes in the two level roadways or the main withdrawal roadway along the working face are divided into two rows, the upper and lower rows of boreholes are arranged in a three-way pattern, the aperture is 75 or 94mm, and the elevation angle of the borehole is generally 1° to 3°. The left and right spacing is 5m~10m, and the upper and lower row spacing is 1.5m~3m.

Described seamless steel pipe (9) and PE pipe (7) each section is 2m, and PE pipe diameter is 32mm, seamless

A cut-off valve (11) is welded at the end of the seamless steel pipe (9) at the orifice.

The double-liquid grouting system described in step 2 consists of a small pneumatic double-liquid grouting pump (14), two pneumatic mixers (13), grouting pipelines and connectors.

The two-liquid grouting material described in step 3 is an inorganic two-liquid quick-setting grouting material.

The single-liquid grouting material is an ultra-fine cement modified material, the water-cement ratio of the material is 0.6-0.8:1, and the uniaxial compressive strength of the 3d age can reach more than 20 MPa.

The single-liquid grouting equipment is mainly composed of a single-liquid high-pressure large-flow hydraulic grouting pump (12) and an electric or pneumatic mixer (13), wherein the rated flow rate of the grouting pump is ≥ 50L/min, and the rated pressure is ≥ 30 MPa.

The beneficial effects of the present invention are:

1. Essentially improving the mechanical properties of the coal body, reshaping the integrity of the broken coal rock, thereby avoiding the occurrence of coal wall fragmentation caused by the impact of mining.

2. The method of forming holes in advance avoids the situation that directly opening holes on the working face will affect the production progress of the working face, and adopts simultaneous grouting operations in the upper and lower level roadways or the main withdrawal roadway on the working face, which greatly shortens the grouting time. Time, fully adapt to the needs of rapid advancement of high-yield and high-efficiency coal mining face.

3. Timely intubation after the borehole is formed can avoid the problem of borehole collapse due to mining, and can make the slurry flow from the deep part of the borehole to the shallow area along the borehole under the action of pump pressure, ensuring the coverage of the entire borehole The reinforcement effect of the region.

4. Choose a reasonable grouting timing, that is, when the advanced bearing pressure area of the working face begins to affect the drilling area, that is, the boundary between the original rock stress area and the stress increase area in Fig. Strong, the grouting effect is obvious, and it can ensure that the grout stone body has a certain strength development time.

5. The single-liquid ultrafine cement modified material is used as the grouting material. Because of its smaller particle size and relatively longer setting time than the double-liquid material, the permeability and diffusion effect of the grout can be greatly improved.

Description of drawings

In order to more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the following will briefly introduce the drawings that need to be used in the description of the embodiments or the prior art. Obviously, the accompanying drawings in the following description are only These are some embodiments of the present invention. Those skilled in the art can also obtain other drawings based on these drawings without creative work.

Figure 1 Schematic diagram of the grouting system;

Fig. 2 schematic diagram of drilling layout of mining roadway;

Fig. 3 schematic diagram of drilling layout of main withdrawal roadway;

Fig. 4 Schematic diagram of the drilling arrangement of the side of the road.

Detailed ways

The following will clearly and completely describe the technical solutions in the embodiments of the present invention with reference to the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only some, not all, embodiments of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by persons of ordinary skill in the art without making creative efforts belong to the protection scope of the present invention.

A technology and method for deep hole grouting in an advanced bearing pressure zone of a fully-mechanized coal mining face, the steps of which include: four technological processes of forming holes in advance, inserting pipes, sealing holes, and grouting in an advanced bearing pressure zone;

(1) Holes formed in advance: the advanced coal mining working face 1≥200m, the hydraulic drilling rig is used to transport the level roadway 2, the return air level roadway 3 or the surface 5 of the main withdrawal roadway along the working face for drilling operations, and the grouting holes are drilled in advance 4. The drilling depth covers the entire length of the working face. The drilling is divided into upper and lower rows on the side of the road. The upper and lower rows of drilling holes are arranged in a three-way pattern. The distance is 2m;

(2) Intubation process: After the hole is formed, insert the PE pipe 7 with a diameter of 32mm into the drill hole one by one at 2m each. The PE pipes 7 are connected by connectors. The pipe 7 needs to be drilled with grouting holes, the hole diameter is 10mm, and the hole distance is 1m; 9 It needs to be wrapped with cotton yarn and tied with iron wire;

(3) Hole sealing process: First, insert a piece of aluminum-plastic pipe 10 with a length of 10m to 20m into the drilled hole and insert cotton yarn 8 at the hole to seal the drilled hole; then, put the aluminum-plastic pipe 10 with double liquid The grouting system is connected; finally, double-liquid grouting material is used to seal the hole. During the sealing process, the aluminum-plastic pipe 10 is slowly pulled out from the inside, and the hole sealing is completed after waiting for 30 minutes for the grout to fully solidify.

When the working face advances to 30mm from the drilling hole, connect the grouting system, select two sets of grouting equipment, and carry out parallel grouting operations on the upper and lower level roads on the working face, and stop the grouting operation and close the stop valve when the pressure reaches 20MPa .

In the grouting process in the advanced support pressure zone, single-liquid grouting equipment and materials are used.

A cut-off valve 11 is welded at the end of the seamless steel pipe 9 at the orifice.

The double-liquid grouting system described in step 2 consists of a small pneumatic double-liquid grouting pump 14, two pneumatic mixers 13, grouting pipelines and connectors.

The two-liquid grouting material described in step 3 is an inorganic two-liquid quick-setting grouting material.

The single-liquid grouting material is an ultra-fine cement modified material, the water-cement ratio of the material is 0.6-0.8:1, and the uniaxial compressive strength of the 3d age can reach more than 20 MPa.

The single-liquid grouting equipment is mainly composed of a single-liquid high-pressure large-flow hydraulic grouting pump 12 and an electric or pneumatic mixer 13, wherein the rated flow rate of the grouting pump is ≥ 50 L/min, and the rated pressure is ≥ 30 MPa.

The above descriptions are only preferred embodiments of the present invention, and are not intended to limit the present invention. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principles of the present invention shall be included in the scope of the present invention. within the scope of protection.

Claims (2)

1. A kind of 1. coal mine fully-mechanized mining working lead abutment pressure area deep hole grouting method, it is characterised in that：Its step includes：In advance Four pore-forming, intubation, sealing of hole, lead abutment pressure area slip casting technological processes；

   （1）Pore-forming in advance：Advanced coal working face（1）>=200m, along working face haulage way（2）, tailgate（3）Or master removes Tunnel（5）Operation of drilling is carried out, is drilled to injected hole in advance（4）, the length of the entire advanced coal working face of drilling depth covering, institute It states along two gallery of working face or the main drilling removed in tunnel and divides two rows, two rows drilling is arranged in a triangular mode, and aperture is 75 or 94mm, the drilling elevation angle are 1 °~3 °, and between left and right away from for 5m~10m, upper and lower array pitch is 1.5 m~3m for drilling；

   （2）Intubation technique：Drilling superficial part in the range of the 10m~20m of aperture away from being inserted into seamless steel pipe（9）, drilling deep is until bottom hole PE pipes need to be inserted into（7）, the seamless steel pipe（9）And PE pipes（7）Often section is 2m, and PE pipe diameters are 32mm, and seamless steel pipe is Six are in charge of, and need winding cotton yarn on the section seamless steel pipe being connected with PE pipes and are fixed with iron wire, the seamless steel pipe at aperture （9）There are one shut-off valves for end weldering（11）；

   （3）Hole-sealing technology：First, the aluminium-plastic pipe for being 10m~20m by a section length（10）It is inserted into drilling and is filled at aperture Cotton yarn（8）Block drilling；Then, by aluminium-plastic pipe（10）It is connected with double-liquid grouting system；Finally, it is carried out using dual-liquid slip-casting material Sealing of hole, during sealing of hole, slowly by aluminium-plastic pipe（10）It pulls out from inside to outside, the double-liquid grouting system is by a small-sized gas Dynamic Double-liquid mud-injection pump（14）, two Pneumatic blenders（13）, grout pipe line and connector composition, the dual-liquid slip-casting material is A kind of inorganic biliquid rapid hardening injecting paste material；

   In lead abutment pressure area grouting process, time for injecting selected as initial stress area increases area's boundary, i.e. work with stress When making the lead abutment pressure coverage covering drilling region in face, advanced coal working face 15m~30m, at this time using two sets Grouting equipment removes parallel operations in tunnel in two gallery of working face or master, using single fluid grouting equipment and material, single liquid Grouting equipment is mainly by single liquid high-pressure high-flow hydraulic grouting pump（12）And electric and pneumatic blender（13）Composition, wherein slip casting Pump metered flow >=50L/min, the MPa of rated pressure >=30.
2. 2. coal mine fully-mechanized mining working lead abutment pressure area deep hole grouting method according to claim 1, it is characterised in that： The single fluid grouting material is superfine cement modified material, which is 0.6~0.8:1,3d age is uniaxial Compression strength is up to more than 20MPa.