CN103953339B - Coal mining machine and coal seam mining method for lump coal mining - Google Patents

Abstract

The invention discloses a coal mining machine for lump coal mining and a coal seam mining method. The coal mining machine includes a fuselage and a cutting part installed on the fuselage. The number of spiral blades set on the cutting part drum is n> And its helix angle is 5°～30°, D and P are the width and pitch of the helical blade respectively; the number m of picks set on each helical blade is determined by the hardness coefficient f of the mined coal seam: when the hardness of the mined coal seam When the coefficient f is 2.5 to 3.5, m=7 to 10 pieces; when the hardness coefficient f of the mined coal seam is greater than 3.5, m=9 to 17 pieces; the mining method includes steps: 1. Mining process parameter setting: set the drum speed 1. Traction speed, cutting thickness, drum rotation direction and cutting depth are set; 2. Coal seam mining adopts one-way coal cutting method. The invention has reasonable structural design, simple method steps, convenient realization and good application effect, and can effectively improve the lump coal rate of the fully mechanized mining face.

Description

Coal mining machine and coal seam mining method for lump coal mining

technical field

The invention belongs to the technical field of coal seam mining, and in particular relates to a coal mining machine for lump coal mining and a coal seam mining method.

Background technique

Because the production of lump coal is affected by many factors such as the strength of the coal seam itself, geological conditions, coal mining technology, and reloading process, the output only accounts for about 10% to 30% of the total output of raw coal. In the process of coal transportation, due to the difference in the drop of the transfer point and the way of coal falling, the lump coals collide with each other when they fall, causing serious loss of lump coal, and the lump coal rate drops by more than 20% to 30% during the transportation process. Therefore, under the mining process conditions of the existing fully mechanized mining face, the coal body is excessively crushed, and the production lump coal rate of the whole mine is low. According to statistics, the lump coal production rate of the existing coal mine is less than 15%, and the pulverized coal production rate is about 85%. The price of pulverized coal is the lowest, and it is mainly sold to power plants. The price of lump coal is more than twice that of pulverized coal. The market prospect is good, and the price difference of different specifications of lump coal is 100 yuan/ton to 150 yuan/ton. See Table 1 for details:

Table 1 Raw Coal Sales Price List

product name Specifications (mm) Price (yuan/ton) pulverized coal <15 210 Coal 15～30 430 small piece 30～60 530 middle block 60～90 750 chunk >90 900

There are many factors affecting the lump coal rate in fully mechanized mining face, and correspondingly there are various ways to increase the lump coal rate. At present, the more popular methods are mainly from the four aspects of equipment optimization, coal mining process improvement, mine pressure utilization and coal seam lithology change as the entry point, and then increase the lump coal rate of fully mechanized mining face. Among them, in terms of equipment optimization, the number of drum picks, the arrangement of drum picks, drum diameter, number of blade heads, blade helix angle and other parameters are mainly optimized. In terms of coal mining process improvement, mainly from reducing the drum speed, changing the drum rotation direction, changing from two-way coal cutting to one-way coal cutting, increasing the cutting depth, appropriately increasing the cutting thickness, and appropriately increasing the traction speed of the shearer, etc. Improvements were made to increase the lump coal rate. At the same time, the coal seam is loosened and blasted through explosive deep-hole blasting technology, and the double-drum shearer is used to cut coal, so as to achieve the purpose of increasing the lump coal rate of the fully mechanized mining face. To sum up, increasing the lump coal rate is an important way to improve the economic benefits of coal production. However, most of the above-mentioned methods to increase the lump coal rate are in the stage of theoretical research, with poor operability, and the effect of increasing the lump coal rate in fully mechanized mining faces is not good. The structural parameters of the shearer and the mining process parameters are an important process of lump coal mining, which directly affect the lump coal rate of the fully mechanized mining face. Therefore, it is necessary to improve the structural parameters and mining process parameters of the existing shearer, so as to give specific guidance to the mining process of the fully mechanized mining face and effectively increase the lump coal rate of the fully mechanized mining face.

Contents of the invention

The technical problem to be solved by the present invention is to provide a lump coal mining coal mine with simple structure, reasonable design, easy operation and good use effect, which can effectively improve the lump coal rate of fully mechanized mining face. machine.

In order to solve the above-mentioned technical problems, the technical solution adopted by the present invention is: a coal mining machine for lump coal mining, including a fuselage and a cutting part installed on the fuselage, and the cutting part includes a rocker arm hinged on the fuselage 1. The drum installed at the front end of the rocker arm and the cutting motor driving the drum, the cutting motor and the drum driving shaft of the drum are connected through a transmission mechanism, characterized in that: There are multiple helical blades on the drum, the number of helical blades Wherein, D is the width of the helical blade, and P is the pitch of the helical blade; the helix angle of the helical blade is 5°～30°;

The number of picks set on each of the spiral blades is m; wherein the value of m is determined by the hardness coefficient f of the mined coal seam: when the hardness coefficient f of the mined coal seam is 2.5 to 3.5, m=7 to 10 m; when the hardness coefficient f of the mined coal seam is greater than 3.5, m=9 to 17.

The above-mentioned coal mining machine for lump coal mining is characterized in that: the number of said spiral blades is n=2-4.

The above-mentioned coal mining machine for lump coal mining is characterized in that: the picks arranged on the spiral blades are arranged in a checkerboard arrangement.

The above-mentioned coal mining machine for lump coal mining is characterized in that: it also includes a grooving member for cutting micro-grooves on the coal wall, and the micro-grooves are straight rectangular grooves; the grooving parts are installed Spiral cutting device or high pressure water jet cutting device on the drum.

The above-mentioned mining machine for lump coal is characterized in that: the helical cutting device is an auger bit, the diameter of the auger bit is 80 mm to 120 mm and the length is 700 mm to 900 mm, and the micro cutting device cut by the helical cutting device is The groove width and groove depth are 80mm~120mm and 700mm~900mm respectively;

The groove width and groove depth of the micro-groove cut by the high-pressure water jet cutting device are 20mm-50mm and 20mm-50mm respectively.

At the same time, the invention also discloses a coal seam mining method using a shearer for lump coal mining with simple steps, reasonable design, convenient implementation, and good use effect. The method is characterized in that the method includes the following steps:

Step 1. Mining process parameter setting: Before mining, set the mining process parameters first, the process is as follows:

Step Ⅰ. Drum speed setting: set the drum speed according to the thickness of the mined coal seam: when the mined coal seam is a thin coal seam with a thickness of 0.8m to 1.5m, the drum speed is 50r/min to 70r/min; When the mined coal seam is a medium-thick coal seam with a thickness of 1.5m~3.5m, the drum speed is 30r/min~50r/min; when the mined coal seam is a thick coal seam with a layer thickness of 3.5m or more, the drum speed is 20r/min ~30r/min;

Step II, traction speed setting: set the traction speed of the shearer to 3m/min-6m/min;

Step Ⅲ, cutting thickness setting: setting the cutting thickness of the shearer drum to 40mm-80mm;

Step Ⅳ, drum rotation direction setting: when the shearer is a double-drum shearer, the drum rotation direction needs to be set; the number of cutting parts installed on the double-drum shearer is two, two The two cutting parts are respectively a front cutting part and a rear cutting part installed on the front and rear sides of the exterior of the fuselage; the drum of the front cutting part is a front drum, and the drum of the rear cutting part is a rear drum. ; The rotation directions of the front drum and the rear drum are opposite, wherein the rotation direction of the front drum is clockwise, and the rotation direction of the rear drum is counterclockwise;

Step Ⅴ, cutting depth setting: set the cutting depth of the drum to 50mm-100mm;

Step 2. Coal seam mining: use the coal shearer and perform coal seam mining according to the mining parameters set in steps Ⅰ to Ⅴ. The coal cutting method used during mining is a one-way coal cutting method.

The above method is characterized in that: the shearer is equipped with a grooving member for cutting micro-grooves on the coal wall, and the micro-grooves are straight rectangular grooves arranged along the length direction of the coal wall; The grooving part is a spiral cutting device or a high-pressure water jet cutting device installed on the drum;

In step 2, during the mining process of the coal seam, one or two micro-cut grooves are cut on the coal wall by using the groove-cutting member, and the two micro-cut grooves are arranged in parallel.

The above-mentioned method is characterized in that: before coal seam mining in step 2, advance pre-splitting of the coal seam from near to far along the advancing direction of the coal seam working face; The coal seam after advanced pre-cracking is mined.

The method described above is characterized in that: when the shearer is a single-drum shearer, in step 2, a one-way coal cutting method is adopted to carry out the mining process, the advanced knife is used to cut coal, and the cutting groove is used in the return process cutting a micro-groove on the coal wall;

When the shearer is a double-drum shearer, the grooving member is installed on the front drum and/or the rear drum; in step 2, the unidirectional coal cutting method is adopted in the mining process, and the advanced knife is used to cut coal , and in the return process, the cutting piece is used to cut one or two micro cutting grooves on the coal wall.

The above-mentioned method is characterized in that: when using the grooving member to cut a micro-groove on the coal wall, the micro-groove cut is located at 1/2 of the mining height of the shearer;

When using the grooving member to cut two micro-grooves on the coal wall, the two micro-grooves cut are respectively located at the 1/3 mining height position and 2/3 mining height position of the coal mining machine. high position.

Compared with the prior art, the present invention has the following advantages:

1. The structure design of the adopted shearer is reasonable and the input cost is low, the operation is simple and the operation effect is good.

2. The structural parameters of the shearer are designed reasonably. The number of spiral blades on the drum and the number and arrangement of the picks on the spiral blades are designed reasonably. coal rate. At the same time, it is equipped with a groove cutting part, which is convenient for processing, manufacturing, installation and layout, and is easy to use and operate, which can further increase the lump coal rate of the fully mechanized mining face.

3. The technological parameters of the shearer are designed reasonably. By limiting the drum speed, traction speed, cutting thickness, drum rotation direction and cutting depth of the shearer, the lump coal rate can be greatly increased.

4. The adopted coal seam mining method has simple steps, reasonable design, convenient implementation and strong operability, and high mining efficiency. It is mainly adjusted comprehensively from multiple aspects such as advanced pre-splitting, shearer structure, and shearer mining technology. It can effectively improve the lump coal rate of the fully mechanized mining face, and the structural parameters of the shearer and the mining process parameters of the shearer are all reasonably designed and easy to implement.

5. Good use effect, high practical value and remarkable economic and social benefits, can effectively increase the lump coal rate of the fully mechanized mining face by 10% to 30%, and the comprehensive recovery rate can reach more than 85%, and it is energy-saving, environmentally friendly, and the mining process Safe and reliable.

To sum up, the present invention has reasonable structural design, simple method steps, convenient implementation and good application effect, can provide specific guidance to the mining process of fully mechanized mining face, and can effectively increase the lump coal rate of fully mechanized mining face.

The technical solutions of the present invention will be described in further detail below with reference to the accompanying drawings and embodiments.

Description of drawings

Fig. 1 is a structural schematic diagram of a shearer drum of the present invention.

Fig. 2 is a schematic diagram of the arrangement state of picks on the helical blade of the shearer drum of the present invention.

Fig. 3 is a schematic structural view of the double-drum shearer of the present invention.

FIG. 4 is a top view of FIG. 3 .

Fig. 5 is a schematic diagram of the installation state of the high-pressure water jet cutting device of the present invention.

Fig. 6 is a flowchart of the mining method of the present invention.

Fig. 7 is a schematic diagram of the installation state of the auger bit of the present invention.

Explanation of reference signs:

1—Fuselage; 2—Front traction unit; 3—Rear traction unit;

4—electric control box; 5—front rocker arm; 6—front roller;

7—front cutting motor; 8—rear rocker arm; 9—rear drum;

10—back cutting motor; 11-1—nozzle; 11-2—high pressure water pipe;

11-3—hydraulic booster; 12—spiral cutting device; 13—spiral blade;

14—pick; 15—drum cylinder; 16—drum drive shaft.

detailed description

Example 1

A coal mining machine for lump coal mining as shown in Fig. 1, Fig. 2, Fig. 3 and Fig. 4 includes a fuselage 1 and a cutting part installed on the fuselage 1, and the cutting part includes a The rocker arm on the top, the drum installed at the front end of the rocker arm and the cutting motor that drives the drum, the cutting motor and the drum drive shaft 16 of the drum are connected through a transmission mechanism; The drum is provided with a plurality of helical blades 13, and the number of helical blades 13 Wherein, D is the width of the helical blade 13, P is the pitch of the helical blade 13; the helix angle of the helical blade 13 is 5°-30°.

The number of picks 14 set on each of the spiral blades 13 is m; wherein the value of m is determined by the hardness coefficient f of the mined coal seam: when the hardness coefficient f of the mined coal seam is 2.5 to 3.5, m=7 ~10; when the hardness coefficient f of the mined coal seam is greater than 3.5, m=9~17.

In this embodiment, the number n=2-4 of the spiral blades 13 .

In actual use, the number n of the helical blades 13 can be adjusted accordingly according to specific needs. That is to say, n spiral blades 13 are arranged on the drum of the shearer, and the n spiral blades 13 form a multi-spiral structure.

The number n of the spiral blades 13 arranged on the drum of the shearer determines the lead S of the spiral blades 13, wherein S=P×n, P is the pitch of the spiral blades 13; and the lead S should not be less than The width D of the helical blade 13 . Therefore, the number of helical blades 13 must satisfy P×n>D, ie n>D/P. In this embodiment, n=2～4, if the number of spiral blades 13 is too much, the distance between adjacent spiral blades 13 will be reduced, and the coal flow space will be narrow, which will increase resistance and energy consumption, and the number of spiral blades 13 will be too large. Too much is not conducive to processing.

In the actual mining process, the larger the helix angle of the spiral blade 13, the greater the coal discharge capacity, but when the helix angle is too large, it is easy to cause coal dust to be crushed; The capacity is small, and the coal circulates inside the spiral blade 13, causing repeated crushing of the coal and reducing the lump coal rate. In this embodiment, after setting the helix angle of the helical blade 13 to 5°-30°, the lump coal rate can be effectively increased.

During actual processing, a plurality of picks 14 are installed on each of the helical blades 13 from outside to inside.

As shown in FIG. 2 , in this embodiment, the picks 14 arranged on the helical blade 13 are arranged in a checkerboard arrangement.

Since the reduction of the number of picks 14 is an effective way to increase the lump coal rate under the condition that the development degree of coal seam fissures and geological conditions permit, the number of picks 14 should be determined according to the coal quality.

In this embodiment, the pick 14 adopted is pick-shaped and knife-shaped, and its installation direction is tangential or radial.

In the actual mining process, when the picks 14 are arranged in a checkerboard manner, two adjacent cutting grooves have been cut out first during the cutting process in the cutting direction, and the formed cutting grooves are symmetrical on both sides, and the chip thickness is large. The block degree and block rate are nearly doubled compared with the sequential arrangement method, and the amount of dust is significantly reduced.

During actual construction, the number of helical blades 13 provided on the drum, the pitch of the helical blades 13, the helix angle of the helical blades 13, and the values of m and n can be adjusted accordingly according to specific needs.

In the actual mining process, when determining the drum diameter of the shearer, choosing a large diameter drum is beneficial to reduce the critical drum speed and improve the coal loading effect, but when the diameter is too large, it will increase energy consumption and reduce coal. Block degree; when the diameter of the drum is too small, the coal charging efficiency will be reduced. In this embodiment, the diameter of the drum of the shearer is 1m-3.5m. In addition, in order to improve the coal loading capacity of the drum, the diameter of the drum body 15 should be as small as possible under the premise of ensuring the welding strength between the screw blade 13 and the drum body 15 and meeting the installation space of the rocker arm transmission device of the shearer. Wherein, the diameter of the cylinder body 15 refers to the diameter of the cylinder body itself, and the diameter of the cylinder refers to the diameter after the helical blade 13 and the pick 14 are installed on the cylinder body. Therefore, the diameter of the drum and the diameter of the drum body 15 should be determined according to specific needs.

At the same time, the coal shearer according to the present invention also includes a groove cutting member for cutting micro-cut grooves on the coal wall, and the micro-cut grooves are straight rectangular grooves. The grooving member is a spiral cutting device 12 or a high-pressure water jet cutting device installed on the drum.

In this embodiment, the grooving member is a high-pressure water jet cutting device. The groove width and groove depth of the micro-groove cut by the high-pressure water jet cutting device are 20mm-50mm and 20mm-50mm respectively.

As shown in Figure 5, the high-pressure water jet cutting device includes a nozzle 11-1 fixedly installed on the drum drive shaft 16 of the shearer drum, and the nozzle 11-1 is connected with a hydraulic pressure booster by a high-pressure water pipe 11-2. Device 11-3 is connected.

During actual installation, the nozzle 11 - 1 is arranged parallel to the drum drive shaft 16 , and the nozzle of the nozzle 11 - 1 is located outside the drum drive shaft 16 .

In actual use, the water is pressurized to 3000 bar through the water pressure booster 11-3, and then a water jet about 3 times the speed of sound is generated through the nozzle 11-1 with a channel diameter of 0.3 mm for cutting.

In this embodiment, the micro-cutting grooves are straight rectangular grooves arranged along the length direction of the coal wall.

As shown in Fig. 3 and Fig. 4, in this embodiment, the coal shearer according to the present invention also includes a front traction part 2 and a rear traction part 3 respectively installed on the front and rear sides of the fuselage 1, respectively installed on the fuselage 1. The front traveling mechanism and the rear traveling mechanism on the front and rear sides of the bottom, and the rocker height adjustment hydraulic system and electrical control system installed in the fuselage 1, and the number of cutting parts installed on the fuselage 1 is two, two The cutting parts are respectively a front cutting part and a rear cutting part installed on the front and rear sides of the fuselage 1, that is to say, the shearer is a double-drum shearer. In actual use, the shearer can also be a single-drum shearer.

The electrical control system includes an electric control box 4 installed on the fuselage 1 and a controller installed in the electric control box 4 . The front cutting part comprises a front rocker arm 5 hinged on the fuselage 1, a front roller 6 mounted on the front end of the front rocker arm 5, and a front cutting motor 7 driving the front roller 6, the front cutting motor 7 is installed in the front rocker arm 5 and carries out transmission connection between it and the front roller 6 through a transmission mechanism. The rear cutting section includes a rear rocker 8 hinged on the fuselage 1, a rear drum 9 mounted on the front end of the rear rocker 8, and a rear cutting motor 10 that drives the rear drum 9. 10 is installed in the rear rocker arm 8 and carries out transmission connection between it and the rear roller 9 through a transmission mechanism. The hydraulic system for raising the rocker arm controls the lifting of the front rocker arm 5 and the rear rocker arm 8 respectively. The front cutting motor 7, the rear cutting motor 10, the front traction unit, the rear traction unit, the front height adjustment hydraulic system and the rear height adjustment hydraulic system are all controlled by the controller.

In this embodiment, the controller adopts a continuously variable speed control system to control the traction rate and the cutting rate (ie, the rotating speed of the drum), so as to improve the coal breaking efficiency of the shearer and achieve energy saving effect. The continuously variable speed control system can adjust the traction speed and cutting speed of the shearer, and can effectively reduce the coal dust on the working face.

The lump coal exploitation as shown in Figure 6 adopts the coal seam mining method of coal cutter, comprises the following steps:

Step 1. Mining process parameter setting: Before mining, set the mining process parameters first, the process is as follows:

Step Ⅰ. Drum speed setting: set the drum speed according to the thickness of the mined coal seam: when the mined coal seam is a thin coal seam with a thickness of 0.8m to 1.5m, the drum speed is 50r/min to 70r/min; When the mined coal seam is a medium-thick coal seam with a thickness of 1.5m~3.5m, the drum speed is 30r/min~50r/min; when the mined coal seam is a thick coal seam with a layer thickness of 3.5m or more, the drum speed is 20r/min ~30r/min.

During actual mining, the rotating speed of the drum has a great influence on the cutting and loading process of the drum. Low drum speed can increase the cutting thickness and increase the lump coal rate; but if the speed is too low, the coal loading effect will be reduced, the cutting power will be increased, and the drum is prone to clogging. If the rotating speed of the drum is too high, the cutting will be too thin, and more pulverized coal will be generated, which will also increase the circulating coal, but the high rotating speed can improve the loading capacity of the drum. In this embodiment, the rotating speed of the drum is set according to the thickness of the coal seam, which can effectively increase the lump coal rate of the working face.

Step II, traction speed setting: set the traction speed of the shearer to 3m/min-6m/min.

When the shearer drum speed is constant, the lump coal rate increases with the increase of traction speed; otherwise, the lump coal rate decreases. From theoretical analysis, the theoretical maximum chip thickness is directly proportional to the pulling speed of the drum, and inversely proportional to the rotating speed of the drum. In order to obtain a larger lump coal rate, the rotating speed of the drum should be as small as possible, and the traction speed should be as large as possible. In this embodiment, the traction speed is set at 3m/min-6m/min, which can increase the lump coal rate to the greatest extent.

Step III, setting of cutting thickness: setting the cutting thickness of the shearer drum to 40mm-80mm.

When the pick 14 of the shearer drum cuts coal and rock, due to the influence of the drum rotation and traction speed, the pick 14 cuts in an arc shape, and its chip shape is crescent. According to the analysis, the cutting thickness and dust amount of the shearer decreased in a hyperbolic trend, and the corresponding lump coal rate also increased. From the perspective of the formation mechanism of coal lumps, when the cutting thickness increases, the volume of the coal body in contact with the pulverized coal core formed by the extrusion of the pick 14 increases, thereby increasing the number of broken pieces and cracks with upward tensile stress. The amount increases and the coal dust decreases. In this embodiment, the cutting thickness of the drum is set at 40 mm to 80 mm, which can effectively increase the lump coal rate.

Step Ⅳ, drum rotation direction setting: when the shearer is a double-drum shearer, the drum rotation direction needs to be set; the number of cutting parts installed on the double-drum shearer is two, two The two cutting parts are respectively a front cutting part and a rear cutting part installed on the front and rear sides of the exterior of the fuselage 1; the drum of the front cutting part is the front drum 6, and the drum of the rear cutting part is Rear drum 9; the rotation directions of the front drum 6 and the rear drum 9 are opposite, wherein the rotation direction of the front drum 6 is clockwise, and the rotation direction of the rear drum 9 is counterclockwise.

When the shearer is a single-drum shearer, there is no need to set the direction of rotation of the drum.

In order to enhance the working stability of the shearer, the steering of the front and rear drums of the double-drum shearer is arranged in opposite directions. In this embodiment, the first method is adopted, that is, the rotation direction of the front drum 6 is clockwise, and the rotation direction of the rear drum 9 is counterclockwise. On the working face, the coal loading effect is good, the coal block is not easy to break, the front roller 6 does not throw coal to the driver, and there is less flying dust.

Step V. Setting the cutting depth: setting the cutting depth of the drum to 50mm-100mm.

In actual mining, a large cutting depth can increase the lump coal rate and reduce coal dust, but an excessively large cutting depth will cause the pick 14 to wear sharply, the cutting force on the single-finger pick 14 will increase, and the force on the pick will increase. Conditions deteriorate, reducing the life of the pick. In this embodiment, the cutting depth is set at 50 mm to 100 mm, which can effectively increase the lump coal rate and lower energy consumption.

During actual mining, the cutting depth of the shearer drum is greater than its cutting thickness.

Step 2. Coal seam mining: use the coal shearer and perform coal seam mining according to the mining parameters set in steps Ⅰ to Ⅴ. The coal cutting method used during mining is a one-way coal cutting method.

In actual mining, a one-way coal cutting method is adopted. Due to the two-way coal cutting mode, when the shearer cuts coal from the nose to the tail, a large amount of coal is accumulated at the front end of the shearer, and they are squeezed and broken. In this embodiment, in order to reduce blockage and increase the lump coal rate, a one-way coal cutting method of feeding from the tail of the machine is adopted.

During actual construction, the drum rotation speed, traction speed, cutting thickness, drum rotation direction and cutting depth of the double drum shearer can be adjusted accordingly according to specific needs.

In this embodiment, the highest lump coal rate can be mined by limiting the drum rotation speed, traction speed, cutting thickness, drum rotation direction and cutting depth of the shearer.

Because the coal shearer is equipped with a cutting piece for cutting micro-cutting grooves on the coal wall, the micro-cutting grooves are straight rectangular grooves arranged along the length direction of the coal wall. In step 2, during the mining process of the coal seam, one or two micro-cut grooves are cut on the coal wall by using the groove-cutting member, and the two micro-cut grooves are arranged in parallel. In this embodiment, the micro-grooves are arranged horizontally.

During actual mining, when using the grooving member to cut one micro-groove on the coal wall, the micro-groove cut is located at 1/2 of the mining height of the shearer.

When using the grooving member to cut two micro-grooves on the coal wall, the two micro-grooves cut are respectively located at the 1/3 mining height position and 2/3 mining height position of the coal mining machine. high position.

In actual use, when the shearer is a single-drum shearer, in step 2, the one-way coal cutting method is used for mining, the advanced knife is used to cut coal, and the high-pressure water jet is used to cut coal during the return process. The device cuts a micro-cut groove on the coal wall. When the shearer is a double-drum shearer, the front drum 6 and the rear drum 9 of the double-drum shearer are equipped with the grooving parts; , cutting coal with the advanced knife, and using the high-pressure water jet cutting device to cut one or two micro-grooves on the coal wall during the return process.

In actual use, during the return process of the shearer (that is, during the empty knife process), after the micro-cut grooves are cut on the coal wall by the high-pressure water jet cutting device, the micro-cut grooves can act as coal seam The cracks make it easier to break the coal wall when the shearer drum cuts the falling coal, and the probability of obtaining large coal lumps is higher, which can effectively improve the lump coal output rate of the coal mining face.

In this embodiment, before the coal seam is mined in step 2, advance the coal seam from near to far along the advancing direction of the coal seam to perform advanced pre-splitting of the coal seam; The coal seam after pre-splitting is mined in advance.

In this embodiment, when performing advanced pre-cracking on the mined coal seam, the method of combining carbon dioxide pre-cracking and hydraulic fracturing is used for advanced pre-cracking, and advanced pre-cracking is carried out in multiple segments from near to far. The advanced pre-cracking methods of the segments are all the same. In actual construction, when performing advanced pre-splitting of the mined coal seam, the deep hole pre-splitting blasting method or the hydraulic fracturing method can also be used for advanced pre-splitting. The deep hole pre-splitting blasting method is carbon dioxide pre-splitting or explosive blasting. Moreover, when the deep hole pre-splitting blasting method or hydraulic fracturing method is used for advanced pre-splitting, the advanced pre-splitting is also performed in multiple segments from near to far.

When the combination of carbon dioxide pre-fracturing and hydraulic fracturing is used for advanced pre-cracking, the process for any segment of advanced pre-cracking is as follows:

Step 101, drilling: drilling pre-splitting boreholes at a position 50m to 150m ahead of the current coal mining face, the number of said pre-splitting boreholes is one or more; the drilling direction of said pre-splitting boreholes is the same as The current coal mining face is arranged in parallel and/or vertically. The length of the pre-splitting borehole is 50m-150m.

Wherein, when drilling the pre-splitting borehole vertically arranged with the current coal mining face, a chamber is excavated at the drilling position, and then the pre-splitting borehole is drilled through the chamber.

During actual construction, when the layer thickness of the coal seam to be mined is not greater than 8m, the pre-splitting borehole is only a borehole arranged in parallel with the current coal mining face; when the layer thickness of the coal seam to be mined is greater than 8m, the The pre-splitting boreholes are only the boreholes arranged perpendicular to the current coal mining face, or include both the boreholes arranged parallel to the current coal mining face, and the boreholes arranged perpendicular to the current coal mining face.

When actually drilling, when the thickness of the coal seam to be mined is greater than 8m, the number of pre-splitting boreholes drilled is multiple, and the multiple pre-splitting boreholes drilled are arranged in layers from top to bottom.

In this embodiment, when the pre-splitting boreholes are arranged in parallel with the current coal mining face, when drilling the pre-split boreholes, the upper and lower troughs at positions 50m to 150m in front of the current coal mining face are Arrange a drilling work point, and then drill a pre-splitting hole perpendicular to the coal seam direction directly from the trough to the coal seam.

In this embodiment, the included angle between the pre-splitting borehole and the horizontal direction in step 101 is not greater than 20°, and the diameter of the pre-splitting borehole is Φ65mm˜Φ105mm and its length is 80m˜150m.

During actual construction, the aperture and length of the pre-splitting borehole and the angle between the pre-splitting borehole and the horizontal direction can be adjusted accordingly according to specific needs.

In this embodiment, the thickness of the coal seam to be mined is 5m-6m, and the number of pre-splitting holes drilled in each pre-splitting segment is one. The pre-split holes drilled are all drill holes parallel to the current coal mining face, and the length of each pre-split segment is 10m-15m.

That is to say, the distance between two adjacent pre-split boreholes is consistent with the length of the pre-split segment, that is, the distance between two adjacent pre-split boreholes is 10m-15m.

Step 102, carbon dioxide pre-splitting: first install carbon dioxide pre-splitting devices in each pre-splitting borehole drilled in step 101 and seal the holes, the length of the sealing holes is 8m to 10m; crack.

In this embodiment, when the carbon dioxide pre-splitters are installed in the pre-splitting boreholes, a plurality of the carbon dioxide pre-splitters are installed in each pre-splitting borehole from front to back along the central axis direction, and the carbon dioxide pre-splitters are The length of the pre-splitter is 1.5m-2.5m and its diameter is Φ50mm-Φ55mm, and the carbon dioxide injected into the carbon dioxide pre-splitter is 0.5kg-1.2kg of liquid carbon dioxide. Radial eruption holes are opened on the side wall of the carbon dioxide pre-splitter. After detonation, the shock wave caused by carbon dioxide gas explodes along the side. The fixing mechanism of the fixing sleeve is activated with the blasting, preventing the carbon dioxide pre-splitter from shooting out from the pre-splitting borehole.

During actual construction, the length and diameter of the carbon dioxide pre-splitter and the weight of liquid carbon dioxide injected into the carbon dioxide pre-splitter can be adjusted accordingly according to specific needs.

In this embodiment, when the carbon dioxide pre-splitter is installed in the pre-splitting borehole, the carbon dioxide gas is installed in the rest of the pre-splitting borehole except for the sealing section of the pre-splitting borehole. A pre-splitter, that is to say, the carbon dioxide pre-splitter is installed at the front end of the pre-splitting borehole.

In this embodiment, the hole is sealed with gun mud. After blasting, the carbon dioxide pre-splitter is recovered for reuse next time.

Step 103, installation of water injection pipes: after carbon dioxide pre-splitting in step 102, high-pressure water injection pipes are installed in each pre-splitting borehole, and the holes are sealed with a length of 8m-10m.

In this embodiment, after the carbon dioxide pre-splitting in step 102 is completed, the sealing sections of each pre-splitting borehole are in a good state, and when the high-pressure water injection pipe is installed in step 103, it is specifically during the carbon dioxide pre-splitting process in step 102 Installed inside the sealing section.

In this embodiment, when performing carbon dioxide pre-splitting, the principle of pre-splitting is the same as that of carbon dioxide explosion. tubes) from front to back into the pre-splitting borehole one by one, and then use detonation current or heating method to quickly convert the carbon dioxide in the carbon dioxide pre-splitting device from liquid to gaseous state, and within about 40ms, the The volume of the carbon dioxide contained expands more than 600 times, and the pressure inside the pipe in the carbon dioxide pre-splitter increases to 270MPa-400MPa. At this time, the carbon dioxide gas passes through the radial eruption holes and explodes outward rapidly. Using the instantaneous strong thrust, the coal body is broken along the natural cracks in the borehole wall, thereby achieving the effect of pre-cracking. The whole process is completed within 1 second.

The head of the carbon dioxide pre-splitter has 2 to 3 pressure relief holes for releasing CO ₂ , and each pressure relief hole is equipped with a pressure relief valve.

In this embodiment, the CO ₂ gas release volume of the carbon dioxide pre-splitter is 150L-600L, the explosion reaction time is about 40ms, and the explosion pressure is 270MPa-400MPa.

When carbon dioxide pre-splitting is actually carried out, the carbon dioxide pre-splitting device is installed at the front end (also called the beginning) of the pre-splitting borehole, and two adjacent carbon dioxide pre-splitting devices are connected by wires. The diameter is consistent with the diameter of the sealed pre-splitting drill hole. During actual installation, the maximum depth of the carbon dioxide pre-splitter into the pre-splitting borehole is about 60 meters, and the installation is performed manually. After blasting, the sealing tube and the carbon dioxide pre-splitter are taken out for reuse.

In actual use, carbon dioxide pre-cracking has the following characteristics:

First, there is no spark in the blasting process, which is especially safe for blasting operations in high-gas mines;

Second, the blasting power is large, and the quantity is large, which reduces the labor intensity of workers, and will not cause the accident of blasting and collapsing people. After blasting, the rate of coal block formation is high, the ratio of pulverized coal is reduced, and there is basically no dust, which greatly reduces the hidden danger of coal dust.

Third, the low pressure detonator is used, and the detonation is safe.

Fourth, there is no destructive shock or shock wave, which reduces the chance of inducing protrusion.

Fifth, there is no need for gun inspection, people can enter after blasting, and can work continuously.

Sixth, the carbon dioxide presplitter is not a civil explosive product, and its transportation, storage and use are exempted from approval, and no special blaster is required.

In this embodiment, when installing a high-pressure water injection pipe, it is also necessary to install a liquid injection system connected to the high-pressure water injection pipe. The liquid injection system consists of a water injection pump (including a pressure pump, a water tank, a pressure gauge, a safety valve, an overflow Valve, etc.), high-pressure steel wire hose, dual-function high-pressure water meter and high-pressure rubber automatic hole sealer.

In this embodiment, the water injection pump adopts BRW200/31.5 emulsion pump.

In actual use, other types of water injection pumps can also be used.

In this embodiment, the high-pressure water pipe is a D50 high-pressure hose. In actual use, other types of high-pressure water pipes can also be used.

Step 104, hydraulic fracturing: injecting water into each pre-fracturing borehole through the high-pressure water injection pipe to perform hydraulic fracturing; at this time, the advanced pre-fracturing process of the current segment is completed.

In this embodiment, when hydraulic fracturing is performed, the water injection pressure is controlled at 8MPa-10Mpa, the penetration radius of water injection is 9m-11m, the water injection time of each pre-splitting borehole is 8-10 days, and the total The water injection volume is 556m ³ to 600m ³ , and the water injection flow rate is 0.3m ³ /h to 2.0m ³ /h.

During actual construction, water injection pressure, water injection penetration radius, water injection time, total water injection volume and water injection volume per unit time can be adjusted accordingly according to specific needs.

Among them, when adjusting the water injection pressure, the water injection pressure should be controlled until a certain degree of water seepage occurs in the coal body; the water injection time of each pre-splitting drill hole is based on the water overflow of the coal body and the obvious increase in water output; according to the actual water injection From the perspective of the situation, the total water injection volume of each pre-splitting borehole is not less than 0.5% of the water content increment of the coal seam; the proportion of active water used is determined according to the softening coefficient of the coal seam on site.

In this example, the method of combining carbon dioxide pre-cracking and hydraulic fracturing is used for advanced pre-cracking. The difference from traditional hydraulic blasting is that water gel explosives that pose a threat to coal mine safety are no longer used, and safe carbon dioxide is used instead. The pre-splitter can also achieve the effect of coal seam crushing and pre-splitting, and the effect of coal seam pre-splitting is better, safer and more reliable.

The present invention combines carbon dioxide fracturing and water deep hole blasting, implements hydraulic fracturing after carbon dioxide fracturing is completed, utilizes artificial cracks formed by carbon dioxide blasting, and performs hydraulic fracturing to further expand the cracks, thereby achieving better coal seam pre-fracture. cracking effect.

In this embodiment, when water is actually injected, the water injected is active water, and a single-pump fan-shaped mixed water injection method is adopted. The injected active water can fully pre-crack and break the coal body and weaken the coal seam.

Step 105 , according to the method described in step 101 to step 104 , perform pre-cracking on the next segment.

Step 106, repeating step 105 multiple times until all the advanced pre-splitting processes of the coal seam to be mined are completed.

In this embodiment, the pre-splitting boreholes drilled in step 101 are all boreholes arranged parallel to the current coal mining face. When the method of combining carbon dioxide pre-cracking and hydraulic fracturing is used for advanced pre-cracking in step 1, the length of each pre-cracking segment is 10m-15m. That is to say, after each advance pre-splitting, the pre-splitting range is in the range of 10m-15m in length. At this point, only one pre-splitting borehole is required per pre-splitting segment.

In the actual construction process, the length of each advanced pre-splitting segment can be adjusted accordingly according to specific needs.

In this embodiment, each advanced pre-splitting section adopts a pre-splitting borehole arranged parallel to the current coal mining face. In addition, the distance between two adjacent pre-splitting boreholes is 10m-15m.

Example 2

As shown in Fig. 7, in this embodiment, the coal shearer used is different from that in Embodiment 1 in that: the groove cutting member is a spiral cutting device 12 installed on the drum of the coal shearer.

In this embodiment, the helical cutting device 12 is driven forward and backward by the push drive mechanism, and the helical cutting device 12 is connected to the push drive mechanism through transmission.

In this embodiment, the helical cutting device 12 is a helical drill bit.

In actual use, the diameter of the auger bit is 80mm-120mm and its length is 700mm-900mm, and the groove width and groove depth of the micro-groove cut by the helical cutting device 12 are 80mm-120mm and 700mm-900mm respectively.

In this embodiment, the diameter of the helical drill is 100 mm and the length is 800 mm, and the width and depth of the micro-grooves cut by the helical cutting device 12 are 100 mm and 800 mm, respectively. During actual construction, the diameter and length of the helical cutting device 12 can be adjusted accordingly according to specific needs.

During actual installation, the auger bit is coaxially connected with the drum drive shaft 16 of the shearer drum and is coaxially installed at the outer end of the drum drive shaft 16 .

In this embodiment, other parts of the structure and parameters of the shearer used are the same as those in Embodiment 1.

In this embodiment, the coal seam mining method adopted is different from that of Embodiment 1 in that: when the shearer is a single-drum shearer, in step 2, a one-way coal cutting method is adopted for mining, and the advanced cutter Coal cutting is carried out, and a spiral cutting device 12 is used to cut a micro-groove on the coal wall during the return process. When the shearer is a double-drum shearer, a spiral cutting device 12 is installed on the front drum 6 and/or rear drum 9 of the shearer; The advanced knife cuts the coal, and in the return process, the spiral cutting device 12 is used to cut one or two micro-cut grooves on the coal wall.

In this embodiment, the remaining steps and process parameters of the adopted coal seam mining method are the same as those in Embodiment 1.

The above are only preferred embodiments of the present invention, and do not limit the present invention in any way. All simple modifications, changes and equivalent structural changes made to the above embodiments according to the technical essence of the present invention still belong to the technical aspects of the present invention. within the scope of protection of the scheme.

Claims (10)

1. A mining machine for lump coal mining, comprising a fuselage (1) and a cutting section mounted on the fuselage (1), the cutting section comprising a rocker arm hinged on the fuselage (1), mounted on The drum at the front end of the rocker arm and the cutting motor that drives the drum, the cutting motor and the drum drive shaft (16) of the drum are connected through a transmission mechanism, and it is characterized in that: The drum is provided with a plurality of helical blades (13), and the number of helical blades (13) Wherein, D is the width of the helical blade (13), and P is the pitch of the helical blade (13); the helix angle of the helical blade (13) is 5°～30°; The number of picks (14) set on each of the spiral blades (13) is m; wherein the value of m is determined by the hardness coefficient f of the mined coal seam: when the hardness coefficient f of the mined coal seam is 2.5 to 3.5, m=7~10; when the hardness coefficient f of the mined coal seam is greater than 3.5, m=9~17. 2. A coal mining machine for lump coal mining according to claim 1, characterized in that: the number of said helical blades (13) is n=2-4. 3. A coal mining machine for lump coal mining according to claim 1 or 2, characterized in that: the picks (14) arranged on the helical blade (13) are arranged in a checkerboard arrangement. 4. A coal mining machine for lump coal mining according to claim 2, characterized in that: it also includes a grooving member for cutting micro-grooves on the coal wall, and the micro-grooves are straight rectangular grooves ; The grooving member is a spiral cutting device (12) or a high-pressure water jet cutting device installed on the drum. 5. A coal mining machine for lump coal mining according to claim 4, characterized in that: the helical cutting device (12) is an auger bit, the diameter of the auger bit is 80mm-120mm and its length is 700mm ~900mm, the groove width and groove depth of the micro-groove cut by the spiral cutting device (12) are 80mm-120mm and 700mm-900mm respectively; The groove width and groove depth of the micro-groove cut by the high-pressure water jet cutting device are 20mm-50mm and 20mm-50mm respectively. 6. A method for coal seam mining using a shearer as claimed in claim 1, characterized in that the method comprises the following steps: Step 1. Mining process parameter setting: Before mining, set the mining process parameters first, the process is as follows: Step Ⅰ. Drum speed setting: set the drum speed according to the thickness of the mined coal seam: when the mined coal seam is a thin coal seam with a thickness of 0.8m to 1.5m, the drum speed is 50r/min to 70r/min; When the mined coal seam is a medium-thick coal seam with a thickness of 1.5m~3.5m, the drum speed is 30r/min~50r/min; when the mined coal seam is a thick coal seam with a layer thickness of 3.5m or more, the drum speed is 20r/min ~30r/min; Step II, traction speed setting: set the traction speed of the shearer to 3m/min-6m/min; Step Ⅲ, cutting thickness setting: setting the cutting thickness of the shearer drum to 40mm-80mm; Step Ⅳ, drum rotation direction setting: when the shearer is a double-drum shearer, the drum rotation direction needs to be set; the number of cutting parts installed on the double-drum shearer is two, two The two cutting parts are respectively a front cutting part and a rear cutting part installed on the front and rear sides of the fuselage (1); the drum of the front cutting part is a front drum (6), and the rear cutting part The cylinder at the top is the rear cylinder (9); the rotation directions of the front cylinder (6) and the rear cylinder (9) are opposite, wherein the rotation direction of the front cylinder (6) is clockwise, and the rotation direction of the rear cylinder (9) The direction of rotation is counterclockwise; Step Ⅴ, cutting depth setting: set the cutting depth of the drum to 50mm-100mm; Step 2. Coal seam mining: use the coal shearer and perform coal seam mining according to the mining parameters set in steps Ⅰ to Ⅴ. The coal cutting method used during mining is a one-way coal cutting method. 7. according to the described method of claim 6, it is characterized in that: described shearer is installed with the groove cutting member that is used for cutting micro-cut groove on coal wall, and described micro-cut groove is straight rectangular groove and its along coal wall The length direction of the wall is arranged; the groove cutting part is a spiral cutting device (12) or a high-pressure water jet cutting device installed on the drum; In step 2, during the mining process of the coal seam, one or two micro-cut grooves are cut on the coal wall by using the groove-cutting member, and the two micro-cut grooves are arranged in parallel. 8. according to the method described in claim 6 or 7, it is characterized in that: before carrying out coal seam mining in the step 2, advance along the coal seam working face advance direction, carry out the advanced pre-cracking of the working face to the mined coal seam from near to far; step 2 When the coal seam is mined in the middle, the coal seam after the advanced pre-cracking is mined from near to far. 9. The method according to claim 7, characterized in that: when the shearer is a single-drum shearer, in step 2, a one-way coal cutting method is adopted to carry out the mining process, and the advanced knife is used to cut coal, and Using the grooving member to cut a micro-groove on the coal wall during the return process; When the shearer is a double-drum shearer, the grooving member is installed on the front drum (6) and/or the rear drum (9); , cutting the coal with the advanced knife, and cutting one or two micro-grooves on the coal wall by using the grooving member during the return process. 10. according to the described method of claim 7 or 9, it is characterized in that: when adopting described grooving member to cut one described miniature grooving on coal wall, the described miniature grooving of cutting is positioned at the position of described shearer. 1/2 mining height position; When using the grooving member to cut two micro-grooves on the coal wall, the two micro-grooves cut are respectively located at the 1/3 mining height position and 2/3 mining height position of the coal mining machine. high position.