CN107905763A - A kind of mash gas pumping drilling Stability Maintenance material and installation aiding device and method - Google Patents

Abstract

The invention relates to a gas drainage drilling stability maintenance material and a device and a method thereof. The device includes a filling material directional pushing device, a sleeve, a porous disk, an end fixing device, a sphere net bag, and a small bearing sphere. The directional pushing device for filling material transports the loaded small balls from the casing to the designated position through the transmission screw. The inner end of the transmission screw is provided with a piston head, and the outer end is connected to the drilling rig. The piston head is located inside the casing. And it is slidingly connected with the inner wall of the casing; the end fixing device is fixed on the coal wall at the gas drainage drilling hole through fixing bolts, and a threaded hole is provided in the center, and the transmission screw passes through the threaded hole; the bearing Small spheres are made by mixing coal gangue with cement. The invention can indirectly adjust the porosity in the gas drainage borehole and the strength of the filling body by changing the diameter of the bearing sphere, and supports the gas drainage borehole to prevent the hole from collapsing while ensuring the permeability of the borehole .

Description

A gas drainage drilling stability maintenance material and layout device and method

technical field

The invention belongs to the technical field of maintaining gas boreholes in this coal seam, and proposes a gas drainage borehole stability maintenance material, a layout device and a method.

Background technique

The stability and maintenance of boreholes for gas drainage along coal seams has always been a key issue in gas prevention and even a difficult problem in the world. With the increase of mining depth, the coal seams mined by most coal mines in my country are soft coal seams, and with the increase of mining depth, gas The pressure is increasing, which makes the hole wall extremely unstable and the borehole is prone to collapse. At present, the method commonly used in mines to prevent gas drilling from collapsing is mainly to install the screen pipe technology in the borehole. Although this method is simple to operate, it has the following disadvantages: usually the screen pipe does not fit tightly with the drill space, and it is easy to cause air leakage; When the hole collapses, it is easy to cause the screen pipe to be squeezed and deformed, and the drainage channel is blocked; when the screen pipe has fewer pores, the single-hole drainage volume is small, and the drainage rate is low; when the screen pipe has many pores, the processing of the screen pipe is more difficult. Difficult and low-strength screen pipes; screen pipes are generally made of high-cost PVC pipes, and the length of drilling holes along the coal seam gas drainage usually reaches tens of meters or even hundreds of meters. After gas drainage, the screen pipes cannot be recycled, which causes great waste of resources. Therefore, in order to save costs, reduce waste of resources, improve hole protection effect and gas drainage rate, a gas drainage drilling stability maintenance material and layout device and method are proposed.

patent content

Aiming at the current problems of high cost and low drainage rate for maintaining the stability of gas drainage boreholes, the present invention provides a maintenance material and layout device and method for gas drainage drilling stability. Hole stability, by adjusting the diameter of the bearing small spheres, indirectly increases the air permeability of the borehole and improves the efficiency of gas drainage.

In order to achieve the above object, the technical solution adopted in the present invention is:

A gas drainage borehole stability maintenance material and layout device, including a filling material directional pushing device, a sleeve, an end fixing device, a small bearing sphere, and a porous disc. The filling material directional pushing device uses a transmission screw to carry The small ball is transported from the casing to the designated position, the inner end of the transmission screw is provided with a piston head, and the outer end is connected to the drilling rig, the piston head is located inside the casing and is slidingly connected with the inner wall of the casing; the end The fixing device is fixed on the coal wall at the mouth of the gas drainage borehole through fixing bolts, and a threaded hole is arranged in the center through which the transmission screw passes.

The casing is made of a thin-walled iron pipe with a section of 2 meters. Both ends of the casing are threaded, and the casings can be combined with each other. After the borehole is filled, the casings can all be recovered.

The end fixing device in the directional pushing device of the filling material is welded by an iron disc and a casing. There are bolt holes around the disc, and the disc can be fixed on the coal wall through the fixing bolts. The iron disc There is a threaded hole in the center; the length of the transmission screw is 2 meters per section, and the transmission screws can be connected to each other through the threads at the ends. The end of the innermost transmission screw is provided with a piston head, and the piston head is made of rubber. The piston head is connected with the drive screw shaft.

The bearing spheres are made by mixing coal gangue, cement and water in a ratio of 5:5:3. The strength of the bearing spheres can reach 0.5MP, and the bearing spheres can meet the strength requirements for maintaining the stability of drilling holes. Coal gangue Both cement and cement are cheap raw materials. After the gas extraction is completed, the bearing spheres do not need to be recycled.

A gas drainage drilling stability maintenance material and layout device and method are carried out according to the following steps:

a. Calculate the diameter of the most suitable carrying sphere according to the borehole size and load-bearing strength requirements, and put the carrying sphere into the sphere mesh bag;

b. After the drilling is completed, put all the pre-calculated bearing spheres into the casing, and then connect the casings in sequence and push them to the first hole protection area in the drilling;

c. Connect the end fixing device with the casing and fix it on the coal wall, and then use the power provided by the drilling rig to make the connected transmission screw push a certain number of bearing small spheres out of the casing and push them to the first hole to be protected area;

d. Remove the end fixing device and a part of the casing and the transmission screw, so that the length of the remaining casing and the transmission screw just reaches the second area to be protected. At this time, follow step c for the second area to be protected. filling;

e. After all the areas to be protected are filled according to the above-mentioned steps, start to seal the holes and prepare for gas extraction.

Compared with prior art, feature and beneficial effect of the present invention are:

(1) The present invention can realize fixed-point protection of boreholes, which will greatly reduce the usage of bearing small spheres and save costs;

(2) The load-bearing sphere of the present invention is prepared by cheap coal gangue and cement, and the load-bearing sphere that joins in the coal will not affect the quality of the coal, so the load-bearing sphere in the borehole does not need to be recycled;

(3) The sleeve pipe of the present invention is a thin-walled iron pipe, which has a good hole protection effect and can be completely recycled.

Description of drawings

1 is a schematic diagram of a gas drainage drilling directional hole protection device and method based on coal gangue;

Fig. 2 is a schematic diagram of a filling material directional pushing device;

Fig. 3 is a schematic diagram of the final filling effect of the present invention;

Fig. 4 is the schematic diagram of carrying small spheroids in the spheroid mesh bag;

Fig. 5 is a schematic diagram of the connection between the drive screw and the piston head;

Among them: 1: Drilling rig; 2: End fixing device; 3: Transmission screw; 4: Internal thread of casing; 5: Piston head; 6: Carrying small ball; 7: Sleeve; ;9: fixed bolt; 10: sealing section; 11: porous disc; 12: drilling stable area; 13: spherical mesh bag

Specific implementation steps

The specific implementation manner of the present invention will be further described below in conjunction with the accompanying drawings.

A directional hole protection device for gas drainage drilling based on coal gangue, including a casing 7, an end fixing device 2, a small bearing sphere 6, and a porous disc 11, and the transmission screw 3 uses the power provided by the drilling rig 1 to drive the small sphere bearing 6 is pushed from the casing to the designated position, and the inner end of the transmission screw is provided with a piston head 5, which is located inside the casing and is slidably connected with the inner wall of the casing; the end fixing device 2 is fixed by The bolt 10 is fixed on the coal wall at the gas drainage drilling hole, and there is a threaded hole in the center through which the transmission screw 3 passes. The casing 7 is made of thin-walled iron pipe with a section of 2 meters , There are threads 4 at both ends of the casing, the casings can be combined with each other, and the casings can all be recovered after the borehole is filled.

The end fixing device in the filling material directional pushing device is welded by an iron disc and a casing, the thickness of the disc is 20cm, and there are bolt holes around it, and the disc can be fixed on the coal wall by fixing bolts 10 , the center of the iron disc has a threaded hole; the length of the transmission screw 3 is 2 meters per section, and the transmission screws can be connected to each other through the threads at the ends. The end of the transmission screw at the innermost end is provided with a piston head 5, and the piston The head 5 is made of rubber material, and the piston head is connected with the transmission screw rod 3-axis.

The bearing sphere 6 is made by mixing coal gangue, cement and water in a ratio of 5:5:3, the strength of the bearing sphere can reach 0.5MP, and the bearing sphere can meet the strength requirements for maintaining the stability of the borehole. Both gangue and cement are cheap raw materials. After the gas extraction is completed, the bearing spheres do not need to be recycled, and the bearing spheres added to the coal during the mining process will not affect the quality of the coal. The walls are all in point contact, which will leave large pores in the borehole, which can be regarded as macroscopic cracks in the coal body, and the gas flow in the borehole is a macroscopic flow, carrying small spheres and the hole wall The contact between them has less hindering effect on gas flow.

A gas drainage borehole stability maintenance material and layout device and method, using the above-mentioned device, and taking the coal seam tendency to drill along the bedding with a length of 80 meters and a borehole diameter of φ75mm as an example, the steps are as follows:

(1) Considering the strength of the bearing sphere and the air permeability in the borehole, the diameter of the bearing sphere is 1 cm;

(2) Loading small spheroids 6 into the spheroid net bag 13, the diameter of the spheroid net bag is consistent with the sleeve pipe, the length of each spheroid net bag is 0.5 meters, the surface of the spheroid net bag is rough, and it will not contact with the hole wall. Sliding occurs, and after the drilling is completed, put the load-bearing spheres that have been loaded into the sphere mesh bag into the casing 7, and then connect the casing through the thread 4 and push it to the first hole protection area in the drilling;

(3) Connect the filling material directional pushing device shown in Figure 2 with the casing and fix it on the coal wall through the fixing bolt 9, and then connect the drilling rig 1 with the transmission screw 3 through the connection head 8, the first section of the transmission screw The 5-axis connection with the piston head is shown in Figure 5. The piston head does not rotate with the transmission screw. The piston head is made of rubber and has high flexibility, which is convenient for pushing the small ball bearing. When the drilling rig is started, the small ball bearing is pushed out of the casing through the transmission screw and pushed. To the first area to be protected hole;

(4) Turn off the drilling rig, remove the end fixing device 2 and a part of the casing and the screw, so that the length of the remaining casing and screw in the drilled hole just reaches the second area to be protected. At this time, follow step (3). The second area to be protected is filled;

(5) After all the areas to be protected are filled according to the appealing steps, the filling spheres are fixed with a porous disk 11;

(6) Seal the hole and prepare for gas drainage. As shown in Figure 3, 12 in the figure is the stable area of the borehole. The wall of the borehole in this area is stable and not easy to collapse, so the area is not filled. hole segment.

Claims (5)

1. a kind of mash gas pumping drilling Stability Maintenance material and installation aiding device, including filler orientation pusher, casing, End fixing device, carrying spherula, sphere mesh bag, porous disc, it is characterised in that：The filler orients pusher Designated position is transported to from casing by spherula is carried by drive screw, drive screw inner end end point is equipped with piston Head, outer termination drilling machine, the piston head are located inside pipe casing and are slidably connected with internal surface of sleeve pipe；The end fixing device passes through Fixing bolt is fixed on the coal wall at mash gas pumping drilling mouth, and center is equipped with a threaded hole, and drive screw is from the threaded hole Pass through；The carrying spherula is made by gangue and cement mixing.

2. a kind of mash gas pumping drilling Stability Maintenance material according to claim 1 and installation aiding device, it is characterised in that： Described sleeve pipe is made of the 2 meters of thin-walled often saved iron pipes, and casing both ends are threaded, and are connected through a screw thread between casing.

3. a kind of mash gas pumping drilling Stability Maintenance material according to claim 1 and installation aiding device, it is characterised in that： End fixing device in the filler orientation pusher is welded for irony disk with casing, and disk surrounding carries Disk, can be fixed on coal wall by bolt hole by fixing bolt, and irony disk center carries threaded hole；The drive screw Length often saves for 2 meters, can be connected with each other between drive screw by the screw thread of end, the drive screw end of innermost end is equipped with piston Head, piston head are made by rubber material, piston head and drive screw axis connection.

4. a kind of mash gas pumping drilling Stability Maintenance material according to claim 1 and installation aiding device, the carrying is small Sphere presses 5 by gangue, cement and water:5:3 ratio is mixed.

5. a kind of mash gas pumping drilling Stability Maintenance material and installation aiding device and method, using described in one of Claims 1-4 4 A kind of mash gas pumping drilling Stability Maintenance material and installation aiding device, it is characterised in that follow the steps below：

A, treating guard aperture region and determining each to treat the spherular quantity of carrying needed for guard aperture region for drilling is predefined, according to brill The pore size and bearing strength demand in hole calculate the spherular diameter of most suitable carrying and carrying spherula are loaded sphere Mesh bag；

B, after drilling drilling, casing is sequentially connected and pushes in drilling first and treats guard aperture region, will be required complete The carrying spherula in portion loads in casing；

C, end fixing device and casing are connected and are fixed on coal wall, recycle the power that drilling machine provides to make what is connected First carrying spherula treated needed for guard aperture region is released casing and push to first by drive screw treats guard aperture region；

D, end fixing device and a part of casing and drive screw are unloaded, makes the length of remaining casing and drive screw just Reach second and treat guard aperture region, at this time, treat that guard aperture region fills to second according to step c；

E, when according to appeal step by all after guard aperture region has filled, with porous disc by carry spherula fix, seal Hole, prepares gas pumping.