CN106285720B - A kind of feeding device of underground coal mine long range spraying system - Google Patents

Abstract

The invention discloses a feeding device for a long-distance grouting system underground in a coal mine, which includes a mixing bin, a material suction pipe, a cyclone collector, a cyclone outlet pipe, a vacuum pump, a shut-off fan, an ejector, an ejector air inlet pipe, Long-distance material delivery pipeline and main air source air compressor. The feeding device of the long-distance grouting system in the coal mine is based on the sufficient gas source in the mine. The negative pressure generated by the vacuum pump will suck the grouting material into the closed cyclone collector, and then the material gas will be separated and the grouting material will enter the shut-off fan. Realize automatic feeding, and use the conveying method of pneumatic conveying, the excess gas in the sprayed material is separated and pumped out by the vacuum pump to make up the main air source, which can make full use of the air source; use the closed fan to pump the sprayed material Pressure conveying realizes the continuous supply of shotcrete materials, reduces pipeline vibration, and then realizes long-distance transportation, reduces the failure rate of pipeline blockage, and reduces the investment cost of underground auxiliary transportation and preliminary auxiliary projects.

Description

A feeding device for long-distance shotcrete system in underground coal mine

technical field

The invention relates to a feeding device for a spraying system, in particular to a feeding device suitable for a long-distance spraying system in a coal mine, and belongs to the technical field of coal mine machinery equipment.

Background technique

The bolt-shotcrete support of coal mine roadway is a support method developed on the basis of the scientific theory of surrounding rock self-stabilization. The concrete sprayed out by the shotcrete system, the bolt and the surrounding rock together form an effective load-bearing arch. , the concrete sprayed out by the shotcrete system plays the role of support, filling, isolation and transformation in the whole support system, which can improve the stability of the roadway and the self-stabilization ability of the surrounding rock. It is the passive support of the current coal mine roadway It is a commonly used support method for active support; at present, most coal mine roadways usually use bolts, anchor cables and metal mesh for combined support and then spray grout to provide additional support to seal the surrounding rock surface in time to prevent surrounding Rock and metal mesh are isolated from air and water, avoiding adverse effects on roadway support due to environmental effects such as surrounding rock weathering, deliquescence and metal mesh corrosion, while removing surrounding rock stress concentration and preventing surrounding rock from loosening.

The spraying system mainly includes two parts: the underground spraying machine for coal mines and the conveying pipeline. According to whether the added raw materials have water or not, the underground spraying machines for coal mines are divided into dry spraying machines and wet spraying machines. Due to wet mixing, the Dust concentration, so wet shotcrete machines are mostly used in underground coal mines at present.

In recent years, the construction technology of coal mine rock roadway engineering in China has developed rapidly. The combination of tunneling smooth blasting technology and anchor shotcrete support makes the roadway take shape at one time, and the monthly footage of inclined shaft construction can continuously reach more than 100 meters. Among them, according to the traditional spraying method, the farthest spraying distance of the spraying machine is only about 200 meters, and it is not only difficult to move the spraying machine and transport materials during construction, but also the cost is high. Due to the limitation of the field, the shotcrete machine has to be installed about 300 meters or even farther away from the shotcrete operation position, which makes it impossible for both the shotcrete machine pipeline and the underground wind pressure to meet the requirements of continuous excavation and spraying and one-time forming of the roadway. Construction requirements, so we can only wait until the roadway excavation forming and bolt support are completed before laying the rails to transport the shotcrete machine and the shotcrete materials for the spraying operation. The grouting time is greatly reduced, and the roadway support effect is greatly reduced; at the same time, the grouting machines used in the existing grouting operations usually require manual mixing and manual feeding, and the labor intensity of the operators is high, and the production efficiency is low; in addition, during long-distance pneumatic conveying, The static pressure of the spraying system is too large, and the problem of air return and material return at the inlet is serious; and in the process of tidal spraying and wet spraying, for example, mixing rice stone, fine sand and cement in a ratio of 2:2:1 Spraying grouting materials with too much water content can easily cause material deposition to block the pipeline, and the pipeline needs to be disassembled and cleaned, and the grouting work efficiency is low.

Contents of the invention

In view of the above problems, the present invention provides a feeding device for a long-distance shotcrete system in a coal mine, which can ensure that the shotcrete material is stirred in a special underground station and transported to the shotcrete working face for a long distance, thereby reducing the amount of auxiliary transportation in the pit and the early stage. Auxiliary engineering input cost, especially suitable for coal mine underground spraying operation.

In order to achieve the above purpose, the feeding device of the long-distance shotcrete system in the coal mine includes a mixing silo, a suction pipe, a cyclone collector, a cyclone outlet pipe, a vacuum pump, a shut-off fan, an ejector, an ejector air inlet pipe, a long The distance between the material delivery pipeline and the main air source air compressor;

The mixing silo is set near the track of the roadway and includes a mixing mechanism;

One end of the suction pipe extends into the bottom of the mixing bin, and the other end communicates with the upper part of the cyclone collector along the tangential direction of the cylinder of the cyclone collector;

The cyclone collector is a vertically arranged airtight conical structure with a large top and a small bottom. The upper end of the cyclone collector communicates with the air inlet end of the vacuum pump through the cyclone outlet pipe, and the lower end of the cyclone collector communicates with the air inlet of the vacuum pump. The feeding end of the shut-off fan is connected;

The air outlet end of the vacuum pump communicates with the air outlet end of the main air source air compressor through a pipeline;

The discharge end of the shut-off fan communicates with the feed end of the injector, the feed end of the injector communicates with the mixing chamber of the injector, and the air inlet end of the mixing chamber rear end of the injector enters the air through the injector. The pipeline communicates with the air outlet of the main air source air compressor, and the outlet of the mixing chamber of the injector is set in a tapered structure with a small front and a large rear, and communicates with the spray nozzle through a long-distance material delivery pipeline.

As a further improvement of the present invention, the feed end of the injector is arranged as a slope structure with a forward inclination angle, and the slope structure is inclined forward and downward to connect with the mixing chamber of the injector.

As a further improvement of the present invention, the rear wall of the feed end of the injector is arranged in a vertical structure, and the rear wall of the vertical structure is vertically connected with the mixing chamber of the injector.

As a further improvement of the present invention, the shut-off fan is a highly air-tight shut-off fan. The shut-off fan includes blades, the top of the blade is fitted with a gap between the inner wall of the housing, and the top of the blade is provided with a groove. It is provided with an elastic sealing strip fixedly connected with it.

As a further improvement of the present invention, a one-way pressure relief port is provided on the casing located on the material-free side in the direction of blade rotation.

As a further improvement of the present invention, the position of the material inlet of the housing and the transition position corresponding to the arc-shaped inner wall of the housing are also provided with an elastic wear-resistant rubber sheet, and the bottom end of the elastic wear-resistant rubber sheet extends out of the arc of the housing. Shaped inner wall, and interference fit with the radius of rotation of the blade.

As a further improvement of the present invention, the main air source air compressor is a screw air compressor.

As a further improvement of the present invention, the cross-sectional shape of the position where the lower end of the cyclone collector is connected to the feed end of the shut-off fan is set to the same structure as the cross-sectional shape of the feed end of the shut-off fan.

As a further improvement of the present invention, the shut-off fan adopts a frequency conversion motor.

As a further improvement of the present invention, the feeding device of the underground long-distance shotcrete system in the coal mine also includes an automatic dumper, which is arranged at a position corresponding to the feeding end of the mixing bin.

Compared with the existing technology, the feeding device of the long-distance shotcrete system in the coal mine is based on the fact that the underground gas source is sufficient, and the negative pressure generated by the vacuum pump sucks the shotcrete material into the closed cyclone collector and then separates the gas. The sprayed material enters the closed fan to realize automatic feeding and is transported by pneumatic conveying. The setting of the vacuum pump not only creates a negative pressure environment in the cyclone collector and the suction pipe, but also mixes the sprayed material during the mixing process. The gas in the air is separated and drawn out by the vacuum pump from the upper end of the cyclone collector to replenish the main gas source, which can make full use of the gas source. At the same time, the automatic feeding method using a negative pressure environment can also avoid the traditional conveyor feeding method. The problem of high air content in the sprayed material; since the traditional vibrating spraying machine is used to pump and transport the sprayed material, the continuous supply of the sprayed material can be realized, the vibration of the pipeline can be reduced, and the long-distance Conveying and reducing the failure rate of pipeline blockage; the feeding device of the long-distance shotcrete system in the coal mine can realize the stirring of the shotcrete material in the underground special station and transport it to the shotcrete working face for a long distance, thereby reducing the underground auxiliary transportation and preliminary auxiliary The project input cost is low, and it is especially suitable for spraying grouting operations in coal mines.

Description of drawings

Fig. 1 is a structural representation of the present invention;

Fig. 2 is the top view of cyclone collector of the present invention;

Fig. 3 is a schematic diagram of the structure of the shut-off fan of the present invention.

In the figure: 1. Stirring bin, 2. Suction pipe, 3. Cyclone collector, 4. Cyclone outlet pipe, 5. Vacuum pump, 6. Shut-off fan, 6-1, shell, 6-2, blade, 6-3. Elastic sealing rubber strip, 6-4. Elastic wear-resistant rubber sheet, 6-5. One-way pressure relief port, 7. Injector, 8. Injector air inlet pipe, 9. Long-distance material delivery pipe, 10. The main air source air compressor.

Detailed ways

The present invention will be further described below in conjunction with the accompanying drawings (hereinafter, the running direction of the material is used as the front description).

As shown in Figure 1, the feeding device of the underground long-distance shotcrete system in this coal mine includes a mixing bin 1, a material suction pipe 2, a cyclone collector 3, a cyclone outlet pipe 4, a vacuum pump 5, a shut-off fan 6, and an injector 7 , Injector air inlet pipeline 8, long-distance material delivery pipeline 9 and main air source air compressor 10.

The mixing silo 1 is set near the rails of the roadway and includes a mixing mechanism.

As shown in FIG. 2 , one end of the suction pipe 2 extends into the bottom of the mixing bin 1 , and the other end communicates with the upper part of the cyclone collector 3 along the tangential direction of the cylinder of the cyclone collector 3 .

Described cyclone collector 3 is the airtight conical structure of up big and down small that is vertically arranged, and the upper end of cyclone collector 3 communicates with the air inlet end of described vacuum pump 5 through cyclone outlet pipe 4, and cyclone collector 3 The lower end communicates with the feed end of the described off fan 6.

The air outlet end of the vacuum pump 5 communicates with the air outlet end of the main air source air compressor 10 through a pipeline.

The discharge end of described shut-off fan 6 is communicated with the feed end of described injector 7, and the feed end of injector 7 is communicated with the mixing chamber of injector 7, and the gas inlet end of the mixing chamber rear end of injector 7 The air inlet pipe 8 of the injector communicates with the outlet end of the air compressor 10 of the main air source. The slurry nozzle is connected.

The feeding device of the long-distance shotcrete system in the coal mine is based on the sufficient gas source in the mine. The shotcrete material is fed into the closed fan 6 through the negative pressure suction device, and is transported by pneumatic conveying.

When in use, as shown in Figure 1, the mine car loaded with grouting materials such as rice stone, yellow sand, concrete, etc. is transported to the vicinity of the mixing silo 1, and the materials are poured into the mixing silo 1 and then injected with water and carried out by the mixing mechanism. Stir evenly, then start the vacuum pump 5, the main air source air compressor 10 and the shut-off fan 6, the pressurized gas enters the ejector 7 through the ejector air inlet pipe 8, and the vacuum pump 5 transfers the air in the cyclone collector 3 and the suction pipe 2 The air is pumped out and sent to the air outlet of the main air source air compressor 10 to supplement the main air source; the evenly stirred sprayed material is sucked through the suction pipe 2 along the tangential direction of the cylinder of the cyclone collector 3 under the action of negative pressure To the inside of the cyclone collector 3, the sprayed material falls into the feeding end of the closed fan 6 in a spiral trajectory along the inner wall of the cyclone collector 3 under its own gravity to complete automatic feeding, and the sprayed material falling into the feeding end of the closed fan 6 The closed fan 3 is continuously and evenly supplied to the injector 7; the sprayed material is separated from gas and solid during the process of falling along the spiral trajectory, and the gas mixed in the sprayed material is separated during the mixing process and is separated from the cyclone collector 3. The upper end is pumped out by the vacuum pump 5 and fed into the main air source. By increasing the height of the cyclone collector 3 or increasing the inner diameter of the cyclone collector 3, the length of the spiral movement of the sprayed material in the cyclone collector 3 can be extended, and then effective gas solidification can be realized. Separation; under the impact of the pressure gas in the shut-off fan 6 and the injector air inlet pipeline 8, the sprayed material that continuously enters the injector 7 enters the long-distance material delivery pipeline 9 for transportation.

The vortex in the mixing chamber of the injector 7 from the high-pressure gas that enters from the injector gas inlet pipeline 8 will cause energy loss, and then affect the blanking speed. Therefore, in order to reduce the vortex energy generated by the high-pressure gas in the mixing chamber of the injector 7, as In a further improvement of the invention, the feed end of the injector 7 is set as a slope structure with a forward inclination angle, and the slope structure is inclined forward and downward to connect with the mixing chamber of the injector 7 .

Due to the large amount of dust and poor spraying effect due to the dry spraying of downhole spraying, the current spraying materials are tide materials containing a certain amount of water, and the accumulation angle of damp materials is relatively large. The slurry material accumulates in the mixing chamber of the injector 7 and is easy to block the injector 7. Therefore, as a further improvement of the present invention, the rear wall of the feed end of the injector 7 is arranged in a vertical structure, and the rear wall of the vertical structure is vertical. Connect directly to the mixing chamber of injector 7.

In order to prevent the high-pressure gas ejected from the ejector air inlet pipe 8 from retrogradely entering the cyclone collector 3 through the shut-off fan 6, as a further improvement of the present invention, the shut-off fan 6 is a highly air-tight shut-off fan, as shown in the figure As shown in 3, the shut-off fan 6 includes a blade 6-2, the top of the blade 6-2 is fitted with a gap between the inner wall of the housing 6-1, the top of the blade 6-2 is provided with a groove, and a groove is provided in the groove to fix it. The connected elastic sealing strip 6-3 is resistant to high temperature and wear; the elastic sealing strip 6-3 can automatically compensate the gap between the blade and the shell, so as to ensure that the shut-off fan 6 has high airtightness.

When the sprayed material enters the injector 7, the air rises up will cause the material to drop badly and affect the material delivery volume. During long-distance pneumatic conveying, the static pressure of the conveying system is relatively high. With the blade 6-2 of the blower 6 When the blade 6-2 rotates upward from the outlet position of the housing 6-1 to the inlet position of the housing 6-1, the high-pressure gas between the blades 6-2 will still pass through the housing 6 The feed inlet of -1 enters the cyclone collector 3, which causes the problem of air rising up and material returning at the feed place. Therefore, in order to further prevent the high-pressure gas ejected from the injector air inlet pipe 8 from passing through the fan 6 during rotation, there will be no material. The gap between the blades 6-2 at the position enters the cyclone collector 3 retrogradely. As a further improvement of the present invention, a one-way The pressure relief port 6-5, during the rotation of the blades 6-2, the high-pressure gas between the blades 6-2 is pressure-relieved and discharged when passing through the one-way pressure relief port 6-5, thereby preventing the high-pressure gas from entering the cyclone collector 3 .

In order to prevent the grouting material particles from clogging between the blade 6-2 and the casing 6-1, thereby causing difficulty in rotation or even blocking the blade 6-2, as a further improvement of the present invention, the casing 6-1 The position of the material inlet and the transition position corresponding to the arc-shaped inner wall of the housing 6-1 are also provided with an elastic wear-resistant rubber sheet 6-4, and the bottom end of the elastic wear-resistant rubber sheet 6-4 protrudes from the arc-shaped inner wall of the housing 6-1 , and interference fit with the size of the radius of rotation of the blade 6-2, when the top of the blade 6-2 passes through the elastic wear-resistant rubber sheet 6-4 during the rotation of the blade 6-2, the elastic wear-resistant rubber sheet 6-4 can effectively clean up the blade that may be stuck 6-2 and the bulk material particles of the housing 6-1, to prevent the blade 6-2 from being stuck.

In order to ensure sufficient conveying strength during the long-distance conveying process, as a further improvement of the present invention, the main air source air compressor 10 adopts a high-pressure and large-air volume screw-type air compressor.

Usually the cross-section of the feeding end of the fan 6 is mostly rectangular or square. In order to realize the continuous and uniform feeding of the fan 6 and prevent the grouting material from falling dead angle, as a further improvement of the present invention, the cyclone The cross-sectional shape of the position where the lower end of the collector 3 is connected to the feeding end of the fan 6 is set to the same structure as the cross-sectional shape of the feeding end of the fan 6, and the same cross-sectional structure can prevent the sprayed material from accumulating on the falling The dead corner of the material does not fall.

In order to realize variable feeding, as a further improvement of the present invention, the shut-off fan 6 adopts an adjustable-speed variable-frequency motor. When used in the underground field, the problem that the material feeding speed of the spraying system is often greater than the material conveying speed often occurs. By changing the frequency of the motor, the speed of the feeder is changed, thereby reducing the feeding amount of the feeder per unit time, and avoiding the plugging of the sprayed material in the mixing chamber of the injector 7 caused by the feeding speed of the material being greater than the conveying speed of the material.

In order to facilitate the dumping of mine trucks carrying shotcrete materials, as a further improvement of the present invention, the feeding device of the long-distance shotcrete system in the coal mine also includes an automatic dumper, which is arranged in the corresponding mixing bin 1 The position of the feed end.

The feeding device of the long-distance shotcrete system in the coal mine is based on the sufficient gas source in the mine. The negative pressure generated by the vacuum pump 5 sucks the shotcrete material into the closed cyclone collector 3, and then the material gas is separated and the shotcrete material enters the closed chamber. Automatic feeding is realized in the fan 6, and the conveying method is conveyed by pneumatic conveying. The setting of the vacuum pump 5 not only creates a negative pressure environment in the cyclone collector 3 and the suction pipe 2, but also mixes the sprayed material in the mixing process The gas is separated and drawn out by the vacuum pump 5 from the upper end of the cyclone collector 3 to supplement the main gas source, which can make full use of the gas source. At the same time, the automatic feeding method using a negative pressure environment can also avoid feeding through the traditional conveyor The problem of high air content in the sprayed material of the method; since the traditional vibrating spraying machine is used to pump and transport the sprayed material, the continuous supply of the sprayed material can be realized, the vibration of the pipeline can be reduced, and the Long-distance transportation, reducing the failure rate of pipeline blockage; the feeding device of the long-distance shotcrete system in the coal mine can realize the stirring of the shotcrete material in the underground special station and transport it to the shotcrete working face for a long distance, thereby reducing the auxiliary transportation and The input cost of auxiliary engineering in the early stage is especially suitable for underground spraying operations in coal mines.

Claims (10)

1. A feeding device for a long-distance grouting system in a coal mine, comprising a mixing bin (1), which is arranged near the roadway rail and includes a stirring mechanism; it is characterized in that it also includes a suction pipe (2), cyclone collector (3), cyclone outlet pipe (4), vacuum pump (5), shut-off fan (6), ejector (7), ejector air inlet pipe (8), long-distance material delivery pipe (9) and main air source air compressor (10); One end of the suction pipe (2) extends into the bottom of the mixing bin (1), and the other end communicates with the upper part of the cyclone collector (3) along the cylinder tangential direction of the cyclone collector (3); The cyclone collector (3) is a vertically arranged airtight conical structure with a large upper part and a smaller lower part. The upper end of the cyclone collector (3) passes through the inlet of the cyclone outlet duct (4) and the vacuum pump (5). The gas end is communicated, and the lower end of the cyclone collector (3) is communicated with the feed end of the described blower fan (6); The gas outlet of the vacuum pump (5) communicates with the gas outlet of the main air source air compressor (10) through a pipeline; The discharge end of described blower fan (6) is communicated with the feed end of described injector (7), and the feed end of injector (7) is communicated with the mixing chamber of injector (7), and injector ( 7) The air inlet end at the rear end of the mixing chamber communicates with the air outlet end of the main air source air compressor (10) through the injector air inlet pipe (8), and the outlet end of the mixing chamber of the injector (7) is set to be front small and rear The large conical structure communicates with the spray nozzle through the long-distance feeding pipeline (9). 2. The feeding device of the long-distance shotcrete system under the coal mine according to claim 1, characterized in that, the feed end of the injector (7) is set to a slope structure with a forward angle, and the slope structure is forward The lower slope is connected to the mixing chamber of the injector (7). 3. The feeding device of the long-distance shotcrete system under the coal mine according to claim 2, wherein the rear wall of the feeding end of the injector (7) is arranged in a vertical structure, and the rear wall of the vertical structure The wall is connected vertically with the mixing chamber of the injector (7). 4. according to the feeding device of claim 1 or 2 or 3 described coal mine long-distance shotcrete system, it is characterized in that, described shut-off blower (6) is a high-airtight shut-off blower, shut-off blower (6) Including the vane (6-2), the top of the vane (6-2) is fit with the inner wall of the housing (6-1), the top of the vane (6-2) is provided with a groove, and the groove is provided with a Elastic sealing strips (6-3) for fixed connection. 5. The feeding device of the long-distance shotcrete system under the coal mine according to claim 4, characterized in that, a one-way Pressure relief port (6-5). 6. The feeding device of the long-distance shotcrete system under the coal mine according to claim 5, characterized in that, the position of the feed port of the housing (6-1) corresponds to the arc of the housing (6-1). The transition position of the shaped inner wall is also provided with an elastic wear-resistant rubber sheet (6-4), and the bottom end of the elastic wear-resistant rubber sheet (6-4) stretches out from the arc-shaped inner wall of the housing (6-1) and is connected with the blade (6-4). -2) The size of the radius of rotation is an interference fit. 7. The feeding device of the coal mine long-distance spraying system according to claim 1, 2 or 3, characterized in that, the main air source air compressor (10) is a screw air compressor. 8. The feeding device of the long-distance shotcrete system under the coal mine according to claim 1, 2 or 3, characterized in that, the lower end of the cyclone collector (3) and the feed end of the shut-off fan (6) The cross-sectional shape of the connected position is set to the same structure as the cross-sectional shape of the feed end of the shut-off fan (6). 9. The feeding device of the coal mine underground long-distance shotcrete system according to claim 1, 2 or 3, characterized in that the shut-off fan (6) adopts a frequency conversion motor. 10. According to claim 1, 2 or 3, the feeding device of the long-distance spraying system under the coal mine is characterized in that, the feeding device of the long-distance spraying system under the coal mine also includes an automatic dumper, an automatic dumper It is arranged at the position corresponding to the feeding end of the mixing silo (1).