RU2181843C1 - Method and unit for extraction of thick coal seams - Google Patents

Abstract

FIELD: mining, particularly powered supports of stoping faces designed for coal extraction from thick seams in underground coal deposit mining. SUBSTANCE: method includes extraction of ground mass by combine with use of unit powered support, preparation of interlayer coal for self-caving, coal discharge after caving through apertures of roofing of powered support units, and coal transportation from interlayer mass by face scraper conveyer. Discharge of coal from interlayer mass is effected by a group of concurrently operated controlled in productivity feeders installed in apertures of roofing of powered support units with formation above powered support units in interlayer mass of one general flow of coal whose velocity is regulated by productivity of feeders. Transportation of coal from all concurrently operating feeders is performed by one face scraper conveyer. Unit for extraction of thick coal seams includes combine, face scraper conveyer, control panel, unitized powered support whose each unit consists of roofing hinged with frame, base, hydraulic props, capping hinged to roofing and control hydraulic jacks connected thereto, hydraulic ram installed on base, device for discharge of self- caving coal from interlayer mass installed in aperture of roofing, plate gate and vibrator. Made in aperture of roofing of each support unit is inclined trapezoidal through for coal discharge rigidly secured to carrying beams of roofing. Mounted in bottom plate of trapezoidal trough is feeder controlled by productivity whose unloading end is located above face scraper conveyer. Plate gate is installed above roofing aperture. Control panel has members of simultaneous engagement in operation of a group of feeders regulated by productivity. EFFECT: reduced losses of coal during extraction and ash content (contamination of coal wit enclosing rocks) due to formation of regulated, with dosed discharge, general flow of coal above powered complex. 3 cl, 6 dwg

Description

 The invention relates to mining, and in particular to mechanized supports for longwall faces, intended for the extraction of coal from powerful seams during underground mining.

 There is a method of mining powerful deposits with a mechanized complex with the release of crushed coal from the interlayer sequence (see, for example, Proceedings of the international symposium on modern mining technology, October, 1988, China, pp. 198-205, Fig. 10, 11), including excavation soil stratum by a mechanized complex with coal output by a downhole scraper conveyor, collapse of the interlayer stratum of coal, individual release of collapsed coal onto a dumped scraper conveyor under the influence of its own weight through windows located near the soil in each ktsii dammed shield support frame, coal transportation of interlayer thickness Zavalny scraper conveyor.

 A disadvantage of the known mining method is the large loss of coal from the interlayer sequence due to its mixing with overlying collapsed rocks of the roof during the formation of many individual coal streams. The capture of roofing rocks by coal streams from the border zone leads to an increase in ash content, an increase in the complexity of controlling a moving stream from the treatment space. The presence of an additional blocking scraper conveyor complicates the mechanized complex, increases its length (without increasing productivity), which requires additional costs for the manufacture and operation of powered roof supports.

 The closest in technical essence is the method of excavating thick seams with the release of coal from the subroofing stratum (see, for example, F. Pera, K. Shimon, J. Nemeth, J. Korbuy. Development of mechanized supports of a new type. Collection of works "Mountain mechanics rocks and mechanized lining "- Novosibirsk, IGD SB RAS USSR, 1985, p. 165-177, Fig. 7). The method includes excavating the soil stratum with a combine using a sectional mechanized lining, preparing the interlayer stratum of coal for self-collapse, releasing coal of this stratum after collapsing through the openings of the sections of the mechanized lining, and transporting coal from the interlayer stratum with a downhole scraper conveyor.

 The disadvantages of the known technical solutions are large losses of coal and clogging of its collapsed rocks. Coal is produced sequentially through openings (openings) of overlapping sections of powered roof supports located on one straight line, while at least on three sides the coal flow zone is in contact with collapsed rocks. Here, the coal flow zone is of small cross-section, the coal is fragmented unevenly, coal may hang during the release process, which leads to a distortion of the flow path and "seizure" of empty rocks from the border zones. In the limited-sized zone of the coal flow of increased coarseness, more fluid collapsed rocks can be introduced from the sides. If coal hangs at high altitude, rock breakthrough is possible from the sides, which leads to coal loss over the floor opening.

 A known unit for the extraction of powerful seams of coal, which implements the specified method for the extraction of powerful seams with the release of coal from the subroofing layer, including a combine harvester, a downhole scraper conveyor, a section mechanized roof support, each section of which consists of a ceiling pivotally connected to the frame, a base, hydroracks, and an upper anti-squeeze screen, pivotally mounted on the floor and connected with a control hydraulic jack, hydraulic jacks of movement mounted on the base, a carbon shutter installed in the opening erekrytiya pivotable in a vertical plane gidrostoykoy control.

 The disadvantage of this technical solution is the difficulty of ensuring high-quality closure of the carbon hatch due to the difficulty of controlling it, which does not allow timely stopping the release and ensuring the safety of the release technology.

 The closest in technical essence is the mechanized roof support section (see, for example, the USSR AS 1830420, Е 21 D 23/00, БИ 28, 1993), including a ceiling pivotally connected to the base with traverses and hydraulic stands, the upper anti-squeezing screen, pivotally mounted on the floor and connected with a control jack, movement jacks installed on the base, a carbon shutter hatch installed in the floor opening with the possibility of rotation in the vertical plane with a water-resistant control, a plate shutter and a rod e cleavers mounted in the side slots overlap. The lining section is equipped with a telescopic shield and a lock, the overlap is made with an additional blocking opening, in which a telescopic shield is installed with the possibility of extension by means of a hydraulic jack. The plate shutter is mounted on a carbon shutter hatch with the possibility of relative rotation and interaction in the final position with a latch that is fixed to the ceiling. At the same time, the core cleavers are pivotally fixed on the sides of the carbon-hatch hatch.

 The disadvantages of the known technical solutions are large losses of coal and clogging of its collapsed rocks due to the release of coal sequentially through each hatch in the sections of the mechanized lining and uncontrollability of self-collapse of coal from the interlayer sequence.

 The technical task of the invention is to reduce coal losses during mining, reduce ash content (clogging by the host rocks) by creating a controlled with a dosed release of the total flow of coal over the mechanized complex.

 The problem is solved in that in a method for excavating powerful coal seams, including excavating the soil stratum with a combine using a sectional mechanized lining, preparing the interlayer stratum of coal for self-collapse, releasing coal of this stratum after collapsing through the openings of the sections of the mechanized lining and transporting coal from the interlayer stratum downhole scraper conveyor, according to the technical solution, coal production from the interlayer stratum is carried out by a group of simultaneously working Tutelo mounted in apertures overlap sections to form the support frame above the support frame sections in a thicker interlayer total coal flow whose speed is controlled capacity feeder, and transport coal from all feeders simultaneously operating produce one downhole scraper conveyor.

 Studies have established that if the outlet openings are dispersed over the area, and the distance between the centers is selected so that the flow zones intersect, then with a simultaneous dosed release of bulk material in the space above the outlet openings, a single flow of moving bulk material is formed.

 If the outlet holes are located on one straight line, then in the lower part the stream is presented in the form of an oval (ellipse), gradually turning into a twist at a height approximately equal to the distance between the extreme outlet holes. If the outlet is conducted from each outlet at the same time, then in the space above these holes several (according to the number of outlet openings) disparate flow zones are formed. The total area of the obtained flow zones at any height will be significantly smaller than the flow zone with simultaneous release.

 In addition, when the distance between the outlet openings is less than the flow zone and the flow zone of adjacent openings intersect each other, when bulk materials are discharged from adjacent outlet openings at the same time. When the collapsed rocks are involved in the adjacent flow zone, they are transferred to the flow zone in which they are discharged, which leads to premature clogging of the collapsed rocks and loss of coal.

 Using the above patterns, the technical solution provides for the simultaneous operation of a group of feeders on one downhole scraper conveyor. In order to control the process of moving self-collapsed coal over sections of mechanized lining, a technical solution provides for the forced release of coal with feeders regulated by productivity.

 The feeder should evenly release coal over the entire area of the ceiling opening, made in the section of the mechanized lining. In addition, the performance of the feeder must be regulated in a wide range.

 The technical solution provides for the simultaneous operation of a group of feeders on one downhole scraper conveyor. The number of feeders working in the group is determined by the technical ability of the downhole scraper conveyor. Given that the feeders operate under approximately the same conditions, their weighted average capacities can be adjusted to the required value of the full load of the downhole scraper conveyor during the work of the group of feeders. If the feeders ensure the release of coal over the entire cross section of the floor opening, and their performance is regulated, then it is possible to form a coal flow in the treatment space with a certain speed. In addition, it is possible to increase the number of simultaneously working feeders, which increases the length of the face, which is a slow lowering of coal and landing of the roof.

 The unit for the extraction of powerful coal seams that implements the proposed method includes a combine harvester, a downhole scraper conveyor, a control panel, a mechanized section support, each section of which consists of a ceiling pivotally connected to the frame, a base, hydroracks, a tower, pivotally mounted on the ceiling and connected to it with hydraulic control jacks, a hydraulic jack of movement, installed on the base, of a device for releasing self-collapsed coal from the interlayer thickness, installed in the opening of the ceiling, slabs th gate and the vibrator.

 According to the technical solution, an inclined trapezoidal chute for the release of coal is made rigidly attached to the supporting beams of the overlap in the overlap opening of each section of the powered lining, and a feeder, adjustable in performance, is mounted in the bottom of the trapezoidal groove, the discharge end of which is located above the bottomhole scraper conveyor, while above the aperture a slab shutter is installed, and the control panel is equipped with elements for the simultaneous inclusion in the work of a group of adjustable production five feeders.

 The inclined trapezoidal chute and the feeder mounted in its bottom, which is adjustable in performance, absorb the pressure of moving coal in the treatment space, and therefore, the technical solution provides for rigid and reliable fastening of the inclined trapezoidal chute to release coal to the supporting beams of the overlapping section of the powered roof support. The elements of the feeder fixing in the bottom of the inclined trapezoidal trough do not have any restrictions and therefore can be made with a sufficient margin of safety.

 The angle of inclination of the walls of the inclined trapezoidal groove for the release of coal to the supporting beams of the overlap is determined by calculations and justified by the maximum possible load distribution from the moving coal stream in the treatment space on it.

 For the release of coal from the interlayer stratum, swinging plunger, plate, scraper feeders are used with the possibility of smooth regulation of performance over a wide range. The technical solution provides for the simultaneous operation of a group of feeders. For this, the control panel is equipped with elements for simultaneous inclusion in the work of feeders regulated by productivity. Feeders should be adjusted to the same average capacity. The number of simultaneously working feeders should satisfy the downhole scraper conveyor's productivity capabilities.

 With the simultaneous operation of groups of feeders in a self-collapsing interlayer thickness of coal, they form a single controlled slowly moving stream. Due to the large area of the coal flow, freezing of collapsed coal is eliminated, favorable conditions are created for self-collapse of overlying rocks (except for hard-to-collapse roofs, where special technological methods are required), which reduces the dynamic load on the lining. In addition, the presence of a single flow eliminates clogging of coal from the side of the roof, only lateral clogging from the side of the worked out space is possible, which can be excluded by special preventive measures.

 The technical solution provides for the installation of a slab shutter above the floor openings, mainly for repair work on the feeder, as well as for unusual situations when it becomes necessary to overlap when breaking through gangue over individual feeders.

 It is advisable to install at least one edge of the floor opening of each section of the powered roof support on its supporting beam a vibrating rod connected through a pusher to a vibrator located under the floor.

 This solution allows the use of a vibrating rod for additional destruction of the stratum simultaneously over two sections of powered roof supports.

The essence of the technical solution is illustrated by an example of a specific design and drawings, where:
in FIG. 1 is a schematic diagram of a method for the extraction of thick seams with the release of coal from the subroofing layer by feeders mounted in the apertures of the overlapping sections of the powered roof support projection onto a vertical plane across the face;
FIG. 2 is the same, section II in figure 1;
FIG. 3 - unit for the extraction of powerful coal seams;
FIG. 4 - node section mechanized lining with a device for the release of self-collapsed coal from the subroofing;
FIG. 5 is the same, section II-II in figure 4;
FIG. 6 is a schematic diagram of mounting a vibrating rod on the edge of the floor opening.

 A powerful coal seam 1 (Fig. 1-3), its layer thickness 2 is taken out by an aggregate 3 with a section mechanized support 4, each section of which is made with a device 5 for releasing self-collapsed coal 6 from the interlayer thickness 7 above the sections of the mechanized roof support 4. Dashed lines 8 in FIG. 2 shows individual zones of flows in the interlayer thickness 7 of self-collapsed coal 6 above each device 5 in sections of powered roofing 4.

 The unit 3 (Fig. 3) for the extraction of coal from powerful seams includes a combine 9, a downhole scraper conveyor 10, a control panel (not shown) by the unit, a mechanized section support 4, each section of which consists of a ceiling 11, pivotally connected to the frame 12, the base 13, the hydraulic stand 14, the upper 15, pivotally mounted on the floor 11 and connected to the control hydraulic jack 16, the hydraulic jacks 17 installed on the base 13, the device 5 for releasing self-collapsed coal 6 from the interlayer thickness 7 installed in the opening 18 (Fig. 4 ) overlap 11 of each section of the powered roof support 4.

 The device 5 (Fig. 4, 5) includes an inclined trapezoidal groove 19 for the release of coal with inclined walls 20 rigidly fixed to the supporting beams 21 of the floor 11. In the bottom of the inclined trapezoidal groove 19, a feeder 22, adjustable in performance, is mounted, which can be made plunger lamellar, scraper, etc. with adjustable performance. As an example in FIG. 4, 5 shows a plunger feeder 22, consisting of a working plate 23, a plunger 24, a hydraulic actuator 25 installed in a window (not shown) of the rear wall 26 of the inclined trapezoidal groove 19. A plate valve 27 is installed above the opening 18 in the ceiling 11. At least on one of the edges of the opening 18 of the overlap 11 of each section of the power support 4 can be mounted on the supports 28 (Fig. 6) a vibrating rod 29 connected through a pusher 30 with a vibrator 31 located under the floor 11. During operation, the vibrating rod 29 makes bending rings baths, the shape of which is shown by dashed lines 32.

 Through-hole 11 (not shown) can be made in the floor 11 to accommodate the working body for drilling holes for preliminary softening of the interlayer coal layer, as well as softening of the underlying hard rocks.

 An example of the method and the operation of the unit for the extraction of powerful coal seams are given below.

 The technological cycle of mechanized mining of a powerful coal seam with the release of self-collapsed coal 6 from the interlayer sequence 7 consists of sequentially performed processes. In the initial position, the sections of the powered support 4 (Fig. 1-3) are closely moved to the chest of the face, their peaks are supported by the console of the interlayer thickness 7 of coal of minimum length (1.5 m). The socks of the bases 13 are located under the downhole scraper conveyor 10. The inclined trapezoidal groove 19 is blocked by a plate shutter 27 (Fig. 5), the track in front of the downhole scraper conveyor 10 is cleaned. After the downhole scraper conveyor 10 is pulled out to the face, the coal mining process by the combine 9 begins in front of the mechanized sectional support 4. Following the excavation of the upper coal strip by the combine 9, the exposed surface of the interlayer thickness 7 of the coal is secured by the upper 15. Then, by the combine 9, the lower coal strip is removed, loading coal downhole scraper conveyor 10 and the cleaning of the soil layer. Mechanized support 4 is ready to repeat the process of coal extraction in front of it. The described process is repeated three times (depends on the capture size of the combine 9).

 The length of the overhanging over the mechanized roof support 4 of the interlayer thickness 7 of coal reaches 1.86 m (when capturing the combine 9, equal to 0.62 m). Then, the interlayer thickness of coal 7 is softened by blasting explosive charges (BB), pumping water under pressure, etc. Open all inclined trapezoidal grooves 19 from the plate shutters 27 and provide the possibility of self-collapse of the interlayer thickness 7 of coal. To increase the efficiency of self-collapse, vibrating rods 29 are included in the work. Then, the procedure for releasing self-collapsed coal 6 (coal destroyed by explosives) is determined by identifying groups of simultaneously working sections of powered roof supports 4. For example, all sections of powered roof support 4 are divided into three groups - the central and two flank . First, over the sections of powered roof supports 4 in the central part, self-collapsed coal 6 is released from the interlayer sequence 7. To do this, include all the feeders 22 in simultaneous operation at the lowest possible productivity.

 The self-collapsed coal 6, produced by all feeders 22, is transported by a downhole scraper conveyor 10. In this case, in the interlayer thickness 7 of the collapsed coal 6, in its central part, a single flow forms over all sections of the powered support 4. A single coal flow 6 provides a smooth lowering of the self-collapsed coal 6 without freezing in the treatment space. If necessary, vibrating rods 29 are included in the operation. In order to increase the productivity of the face, the productivity of the group of feeders 22 is increased, which increases the speed of the self-collapsed coal 6 from the interlayer thickness 7 and allows you to adjust the flow rate of the self-collapsed coal 6 in the treatment space.

 The low speeds of movement of self-collapsed coal 6 in the treatment space, which regulate, ensure the safety of coal production. The self-collapsed coal 6 from the interlayer sequence 7 moves in a narrow stream, which excludes its mixing with the surrounding rocks, and the slowly moving stream through the device 5 for the release of self-collapsed coal 6 and the ease of its regulation (up to a stop) reduces clogging of the surrounding rocks.

 After the release from the central part of the self-collapsed coal 6 from the interlayer sequence 7, coal is also similarly released from the flank groups. Moreover, the more simultaneously working feeders 22 in the group, the smoother the process of releasing self-collapsed coal 6 from the interlayer sequence 7.

Claims (3)

 1. The method of excavation of powerful coal seams, including excavation of the soil stratum with a combine using a sectional mechanized lining, preparation of the interlayer stratum of coal for self-collapse, the release of coal of this stratum after collapse through the openings of the sections of the mechanized lining and transporting coal from the interlayer stratum with a downhole scraper conveyor, characterized in that the coal production from the interlayer stratum is carried out by a group of simultaneously working feeders controlled by productivity, installed in the openings of the section ceilings mechanized lining with the formation over the sections of mechanized lining in the interlayer thickness of one common stream of coal, the speed of which is regulated by the capacity of the feeders, and the transportation of coal from all simultaneously working feeders is carried out by one downhole scraper conveyor.  2. A unit for the extraction of powerful coal seams, including a combine harvester, a face scraper conveyor, a control panel, a mechanized section support, each section of which consists of a ceiling pivotally connected to the frame, a base, hydroracks, a tower, articulated to the ceiling and connected with hydraulic jacks control, hydraulic jack installed on the basis of the device for the release of self-collapsed coal from the interlayer thickness installed in the opening of the ceiling, slab shutter and vibrator, excellent This is because an inclined trapezoidal chute for coal discharge is made in the overlap opening of each section of the powered lining, rigidly attached to the supporting beams of the overlap, and a feeder, adjustable in performance, is mounted in the bottom of the trapezoidal groove, the discharge end of which is located above the bottomhole scraper conveyor, while above the aperture a slab shutter is installed, and the control panel is equipped with elements for simultaneous inclusion in the work of a group of feeders regulated by productivity.  3. The assembly according to claim 2, characterized in that at least on one edge of the opening of the overlap of each section of the powered roof support, a vibrating rod is mounted on the supports on its supports, which is connected via a pusher to a vibrator located under the overlap.

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