Top coal caving filling mining net laying slurry blocking support and slurry blocking method

Abstract

The invention relates to a top coal caving filling mining net laying slurry blocking support and a slurry blocking method, and belongs to the technical field of coal mining equipment. The support comprises a top coal caving hydraulic support, an automatic net laying device and an isolation slurry blocking device. The top coal caving hydraulic support is composed of a reverse four-connecting-rod support body, a split type shield beam mechanism and a coal caving mechanism and can adapt to different mining conditions. The automatic net laying device unfolds a separation net through an electric driving device, the speed is matched with the frame moving speed, and full coverage of the upper surface of the coal seam is achieved. The isolation slurry blocking device adopts isolation slurry blocking cloth of a five-layer composite structure, and the isolation slurry blocking cloth is unfolded and tension is adjusted through an electric driving device, so that slurry is effectively prevented from rushing into a bracket and a working surface. According to the method, through cooperation of all the devices, efficient and smooth operation of processes such as coal caving, net laying and slurry blocking is achieved, the stability of a filling body is remarkably improved, the risk that slurry flows into the filling body in the filling process is reduced, and mining safety is guaranteed.

Description

Technical Field

[0001] The present invention relates to the technical field of coal mining equipment, and particularly to a reticulating slurry-blocking support for top coal caving and filling mining and a slurry isolation method. Background Art

[0002] The development of coal mining technology has always revolved around three core objectives: safety, high efficiency, and environmental protection. In the field of thick coal seam mining, the top coal caving mining technology has been widely used due to its high recovery rate advantage, while the filling mining technology has attracted much attention due to its outstanding effect in controlling surface subsidence. In recent years, the top coal caving and filling mining technology that combines the advantages of both has gradually become a research hotspot, but there are still many technical challenges in practical applications.

[0003] Although the traditional top coal caving mining technology can achieve the efficient mining of thick coal seams, it is prone to problems such as roof collapse and surface subsidence during the mining process, which have a serious impact on the ecological environment of the mining area. At the same time, the risk of gas accumulation and water inrush in the goaf has always been a safety hazard. Although the filling mining technology can effectively control surface subsidence, it often has problems such as low filling efficiency and complex processes in thick coal seam mining, and it is difficult to meet the high-yield and high-efficiency mining requirements.

[0004] In the prior art, the design of hydraulic supports often only focuses on a single function: either focusing on top coal caving mining or emphasizing filling support. This functional singularity leads to obvious technical shortcomings in the process of top coal caving and filling mining: one is the lack of effective isolation measures, and the filling slurry is easy to penetrate into the working face, affecting normal production; the other is that the reticulating process does not closely match the mining process, and it is difficult to form a complete isolation layer; the third is that the intelligent level of the slurry-blocking device is insufficient and it cannot be adjusted in real time according to the mining conditions. Especially in the mining of steeply inclined extra-thick coal seams, these problems are more prominent. Due to the large coal seam dip angle and thickness, the stability and adaptability of traditional supports are significantly insufficient, and situations such as filling body slippage and uneven stress on the supports often occur, seriously threatening mining safety. In addition, the existing slurry-blocking materials perform poorly in terms of compressive strength, wear resistance, and sealing performance, and it is difficult to meet the requirements of high-pressure filling conditions. In terms of control technology, traditional mechanical control or simple electrical control is difficult to achieve the precise matching of the reticulating speed and the support moving speed, as well as the real-time adjustment of the tension of the slurry-blocking cloth. This lack of control precision often leads to poor process connection, affecting the overall mining efficiency, and may even cause safety accidents.

[0005] In summary, there is an urgent need to develop a new type of hydraulic support system that integrates the functions of coal caving, reticulating, and slurry blocking and has intelligent control capabilities to solve the key technical problems in top coal caving and filling mining and promote the development of coal mining technology towards a safer, more efficient, and more environmentally friendly direction. Summary of the Invention

[0006] The object of the present invention is to overcome the deficiencies in the prior art and provide a support for laying net and blocking slurry in top coal caving filling mining and a slurry isolation and blocking method. By integrating an automatic net laying device and an isolation and blocking slurry device, the laying of the isolation net on the upper surface of the coal seam and the effective blocking of the slurry are realized, thereby improving the stability of the filling body, reducing the risk of the slurry flowing into the support and the working face, and ensuring the safety and efficiency of the mining process.

[0007] To achieve the above object, the present invention provides a support for laying net and blocking slurry in top coal caving filling mining:

[0008] A top coal caving hydraulic support, including a reverse four-link support main body, a split shield beam mechanism and a coal discharging mechanism; the reverse four-link support main body is located at the front of the top coal caving hydraulic support and is hinged to the split shield beam mechanism through a base, the split shield beam mechanism is located at the rear of the top coal caving hydraulic support, and its shield beam is connected to the base through a shield beam lifting oil cylinder and a shield beam swing angle oil cylinder; the chute of the coal discharging mechanism is inserted into the interior of the shield beam and is driven to extend and retract through a chute telescopic oil cylinder.

[0009] An automatic net laying device, including an isolation net, a fixed pin, a rotating shaft and an electric driving device, the rotating shaft is installed below the shield beam through the fixed pin, and the isolation net is wound around the rotating shaft and is unfolded through the electric driving device.

[0010] An isolation and blocking slurry device, including an isolation and blocking slurry cloth, a fixed pin, a rotating shaft and an electric driving device, the rotating shaft is fixed below the shield beam through the fixed pin, and one end of the isolation and blocking slurry cloth is wound around the rotating shaft and is unfolded through the electric driving device.

[0011] Wherein, the reverse four-link support main body includes a bearing beam, a reverse four-link mechanism, two groups of hydraulic columns and a base, the reverse four-link mechanism is hinged to the bearing beam, and the hinge angle is 15° to 45°, and the two groups of hydraulic columns include a front column and a rear column, which are respectively hinged to the bearing beam and the base.

[0012] A new support structure integrating a top coal caving hydraulic support, an automatic net laying device and an isolation and blocking slurry device is provided. Through the coordinated cooperation of each device, the efficient and smooth operation of processes such as coal discharging, net laying and slurry blocking is realized, effectively solving the problems that it is difficult to control the stability of the filling body in traditional mining, the slurry is easy to flow into the interior of the support or shear and slide, significantly improving the stability of the filling body, and ensuring the safety and efficiency of the mining process.

[0013] Further, the split shield beam mechanism includes a shield beam, a shield beam lifting column, a shield beam lifting oil cylinder and a shield beam swing angle oil cylinder, the lower end of the shield beam lifting column is fixed to the base, and the upper end is hinged to the shield beam, the shield beam lifting oil cylinder and the shield beam swing angle oil cylinder are respectively hinged to the shield beam and the base, and the length of the shield beam is adjustable to adapt to different mining conditions.

[0014] The design of the split shield beam mechanism enables the support to adapt to different mining conditions by adjusting the lengths of the shield beam and the telescopic beam, enhancing the flexibility and applicability of the support. It can better cope with complex and changeable geological environments and coal seam structures, improving the versatility and service life of the support.

[0015] Furthermore, the coal discharging mechanism includes a chute and a chute telescopic oil cylinder. The chute is inserted behind the shield beam, and the telescopic length ΔS is controlled by the chute telescopic oil cylinder. The relationship between the telescopic length ΔS of the chute and the swing angle α3 of the shield beam is as follows:

[0016] H - Δh = (S + ΔS)cosα3

[0017] Where, H is the height of the support, Δh is the safety clearance between the top of the shield beam and the bearing beam and Δh≥50mm, S is the initial length of the shield beam, and α3 is the horizontal swing angle of the shield beam.

[0018] It clarifies the dynamic matching relationship between the telescopic length of the chute and the swing angle of the shield beam in the coal discharging mechanism, ensuring that the coal discharging port is fully opened, thereby optimizing the coal discharging process, improving the coal discharging efficiency, and at the same time ensuring the smoothness and safety of the coal discharging process, reducing the stability problems of the filling body caused by insufficient or uneven coal discharging.

[0019] Furthermore, the isolation and slurry blocking cloth is a five - layer composite structure, including:

[0020] The outer layer is graphene - coated polyester fiber with a thickness of 0.2mm;

[0021] The compressive layer is an aramid fiber woven mesh with a thickness of 0.5mm;

[0022] The isolation layer is a microporous PTFE membrane with a thickness of 0.1mm;

[0023] The strengthening layer is a stainless steel wire mesh with a thickness of 0.3mm;

[0024] The inner layer is a wear - resistant polyurethane coating with a thickness of 0.4mm;

[0025] The total thickness of the isolation and slurry blocking cloth is 1.5mm, and the areal density is 1800g / m 2 , and the bursting strength ≥1.2MPa. The isolation and slurry blocking cloth adopts a five - layer composite structure, having excellent compressive, isolation, wear - resistant and corrosion - resistant properties. The total thickness and areal density are moderate, and the bursting strength is high. This high - performance slurry blocking cloth can effectively prevent the slurry from flowing into the support and the working face, reducing the risk of slurry leakage, ensuring the cleanliness and safety of the working face, and at the same time extending the service life of the slurry blocking cloth and reducing the maintenance cost.

[0026] Furthermore, a slurry separation and blocking method based on the caving and filling mining mesh-laying and slurry-blocking support is also provided, including the following steps:

[0027] S1. Synchronize support moving and mesh laying: When the support is advanced, the isolation net is deployed through the electric drive device, and the isolation net is laid on the upper surface of the lower section coal seam at a rate matching the support moving speed and flattened by the rear scraper conveyor.

[0028] S2. Coal caving: Control the swing angle cylinder of the shield beam to rotate the shield beam, and at the same time retract the ejector plate. After the top coal collapses, it is transported out by the rear scraper conveyor.

[0029] S3. Slurry blocking: After coal caving is completed, control the lifting cylinder of the shield beam to lower the shield beam, deploy the isolation slurry-blocking cloth to a length greater than the sum of the maximum extended lengths of the shield beam and the ejector plate, fix the isolation slurry-blocking cloth at the bottom end of the ejector plate, and adjust the tension of the isolation slurry-blocking cloth to 50 - 200 N / m.

[0030] S4. Filling and grouting: Real-time monitor the tension of the isolation slurry-blocking cloth through the PID controller, and adjust the torque of the electric drive device. The equation is:

[0031]

[0032] where T is the output torque, e(t) is the deviation between the tension set value and the actual value, and K p 、K i 、K d are PID control parameters.

[0033] A slurry separation and blocking method based on a new type of support is provided. Through the coordinated cooperation of steps such as synchronizing support moving and mesh laying, coal caving, slurry blocking, and filling and grouting, the efficient and stable operation of the entire mining process flow is achieved. This method can effectively control the stability of the filling body, reduce the risk of slurry flowing into the support interior, ensure the safety and efficiency of the mining process, and at the same time improve the quality and stability of the filling body.

[0034] Furthermore, the matching error between the mesh laying speed and the support moving speed in step S1 is less than 3%. The rotation speed of the rotating shaft is adjusted through the multi-node PID control algorithm, further optimizing the mesh laying process. By adjusting the rotation speed of the rotating shaft through the multi-node PID control algorithm, it is ensured that the matching error between the mesh laying speed and the support moving speed is less than the specified value. This precise control method further improves the mesh laying quality and efficiency, avoids problems such as uneven and irregular laying of the isolation net caused by unmatched mesh laying speeds, and thus better ensures the stability of the filling body.

[0035] Furthermore, the electric drive device of the automatic mesh laying device adopts the multi-node PID control algorithm, and the control equation is:

[0036]

[0037] Among them, ΔL is the difference between the actual support moving speed and the set net laying speed, and the difference is less than 3%, K p is the proportionality coefficient, K i is the integral coefficient, K d is the differential coefficient.

[0038] The automatic net laying device adopts a multi-node PID control algorithm, which can accurately control the unfolding speed of the isolation net to match the support moving speed, with an error less than the specified value. This precise control method ensures that the isolation net can be evenly and smoothly laid on the upper surface of the coal seam, avoiding the problem of the stability of the filling body caused by uneven net laying, and improving the net laying quality and mining efficiency.

[0039] Furthermore, the tension of the isolation slurry blocking cloth in step S3 is real-time fed back to the PID controller through the tension sensors arranged at the end of the plug board, the middle part of the shield beam and the rotating shaft. By arranging the tension sensors at the end of the plug board, the middle part of the shield beam and the rotating shaft and transmitting the real-time fed-back tension data to the PID controller, the precise monitoring and adjustment of the tension of the isolation slurry blocking cloth are realized. This real-time feedback and adjustment mechanism can ensure that the slurry blocking cloth always maintains an appropriate tension, effectively blocking the slurry from pouring into the support and the working face, and improving the slurry blocking effect and mining safety.

[0040] Furthermore, the coal caving process in step S2 is sequential single-frame or group coal caving, and the swing angle α3 of the shield beam is dynamically matched with the telescopic length ΔS of the plug board to ensure that the coal caving opening is fully opened, clarifying the dynamic matching relationship between the swing angle of the shield beam and the telescopic length of the plug board in the coal caving process, ensuring that the coal caving opening is fully opened, and optimizing the coal caving process. This dynamic matching method can improve the coal caving efficiency, reduce the problem of the stability of the filling body caused by insufficient or uneven coal caving, and at the same time ensure the smoothness and safety of the coal caving process, improving the mining efficiency and quality.

[0041] Furthermore, after the isolation slurry blocking cloth in step S3 is unfolded, the lifting cylinder of the shield beam controls the shield beam to rise to a safety gap Δh≥50mm with the bearing beam to form a continuous slurry blocking barrier. By controlling the shield beam to rise to the safety gap with the bearing beam through the lifting cylinder of the shield beam to form a continuous slurry blocking barrier, the slurry blocking effect is further enhanced. This continuous slurry blocking barrier can effectively prevent the slurry from pouring into the support and the working face, ensuring the cleanliness and safety of the working face, and at the same time improving the stability of the filling body and reducing the risk of slurry leakage.

[0042] Compared with the prior art, a caving and backfilling mining net-laying and slurry-blocking support of the present invention includes a caving hydraulic support, an automatic net-laying device, and an isolation slurry-blocking device. The caving hydraulic support includes a reverse four-bar linkage support body, a split shield beam mechanism, and a coal-discharging mechanism, and can adapt to different mining conditions. The automatic net-laying device unfolds the isolation net through an electric driving device to realize a net-laying process matching the support moving speed. The isolation slurry-blocking device adopts an isolation slurry-blocking cloth with a five-layer composite structure, unfolds and adjusts the tension through an electric driving device, and effectively blocks the slurry from flowing into the support and the working face. Through the coordinated cooperation of each device, the present invention realizes the efficient and smooth operation of processes such as coal discharging, net laying, and slurry blocking, significantly improves the stability of the filling body, reduces the risk of slurry inflow, and ensures the safety and efficiency of the mining process. Description of the Drawings

[0043] Figure 1 It is a schematic structural diagram of the caving and backfilling mining net-laying and slurry-blocking support provided by an embodiment of the present invention;

[0044] Figure 2 It is a schematic diagram of the structural parameters of the caving and backfilling mining net-laying and slurry-blocking support provided by an embodiment of the present invention;

[0045] Figure 3 It is a schematic diagram of the net-laying process of the caving and backfilling mining net-laying and slurry-blocking support provided by an embodiment of the present invention;

[0046] Figure 4 It is a schematic diagram of the slurry-blocking process of the caving and backfilling mining net-laying and slurry-blocking support provided by an embodiment of the present invention;

[0047] Figure 5 It is a schematic diagram of the process connection time sequence of the caving and backfilling mining net-laying and slurry-blocking support provided by an embodiment of the present invention;

[0048] Reference numeral description: 1. Bearing beam; 2. Front column; 3. Reverse four-bar linkage mechanism; 4. Shield beam lifting oil cylinder; 5. Shield beam lifting column; 6. Shield beam; 7. Shield beam swing angle oil cylinder; 8. Slurry-blocking cloth; 9. Scraper telescopic oil cylinder; 10. Scraper; 11. Rear scraper conveyor; 12. Fixed pin; 13. Rotating shaft; 14. Isolation net; 15. Rear column; 16. Base. Detailed Embodiment

[0049] The present invention will be further described below with reference to the drawings. The following embodiments are only used to more clearly illustrate the technical solution of the present invention, and cannot be used to limit the protection scope of the present invention.

[0050] In the description of the present invention, it should be understood that the orientation or positional relationship indicated by terms such as "center", "axial direction", "lateral direction", "upper", "lower", "inner", "outer", etc. is based on the orientation or positional relationship shown in the drawings. It is only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation. Therefore, it should not be construed as a limitation to the present invention. In addition, terms such as "first", "second", etc. are only used for descriptive purposes and cannot be understood as indicating or implying relative importance or implicitly specifying the quantity of the indicated technical features. Thus, features defined with "first", "second", etc. may explicitly or implicitly include one or more of such features. In the description of the present invention, unless otherwise specified, the meaning of "a plurality of" is two or more.

[0051] In the description of the invention, it should be noted that unless otherwise clearly specified and limited, the terms "installation", "connection", and "coupling" shall be understood in a broad sense. For example, it may be a fixed connection, a detachable connection, or an integral connection; it may be a mechanical connection or an electrical connection; it may be directly connected or indirectly connected through an intermediate medium, and it may be the communication inside two elements. For those of ordinary skill in the art, the specific meanings of the above terms in the present invention can be understood through specific circumstances.

[0052] The present invention provides a caving and filling mining net-laying and slurry-blocking support, including: a caving hydraulic support, including an inverted four-link support main body, a split shield beam mechanism, and a coal discharging mechanism; the inverted four-link support main body is located at the front of the caving hydraulic support and is hinged to the split shield beam mechanism through a base 16. The split shield beam mechanism is located at the rear of the caving hydraulic support, and its shield beam 6 is connected to the base 16 through a shield beam lifting oil cylinder 4 and a shield beam swing angle oil cylinder 7; the coal discharging mechanism's chute 10 is inserted into the inside of the shield beam 6 at the back and is driven to extend and retract through a chute telescopic oil cylinder 9.

[0053] An automatic net-laying device, including a separation net 14, a fixed pin 12, a rotating shaft 13, and an electric driving device. The rotating shaft 13 is installed below the shield beam 6 through the fixed pin 12, and the separation net 14 is wound around the rotating shaft 13 and is unfolded through the electric driving device.

[0054] A separation and slurry-blocking device, including a separation and slurry-blocking cloth 8, a fixed pin 12, a rotating shaft 13, and an electric driving device. The rotating shaft 13 is fixed below the shield beam 6 through the fixed pin 12, and one end of the separation and slurry-blocking cloth 8 is wound around the rotating shaft 13 and is unfolded through the electric driving device.

[0055] The anti-four-link support main body includes a bearing beam 1, an anti-four-link mechanism 3, two groups of hydraulic columns, and a base 16. The anti-four-link mechanism 3 is hinged to the bearing beam 1, and the hinge angle is 15° to 45°. The two groups of hydraulic columns include a front column 2 and a rear column 15, which are respectively hinged to the bearing beam 1 and the base 16.

[0056] Further, the split shielding beam mechanism includes a shielding beam 6, a shielding beam lifting column 5, a shielding beam lifting oil cylinder 4, and a shielding beam swing angle oil cylinder 7. The lower end of the shielding beam lifting column 5 is fixed to the base 16, and the upper end is hinged to the shielding beam 6. The shielding beam lifting oil cylinder 4 and the shielding beam swing angle oil cylinder 7 are respectively hinged to the shielding beam 6 and the base 16. The length of the shielding beam 6 is adjustable to adapt to different mining conditions.

[0057] Further, the coal caving mechanism includes a chute 10 and a chute telescopic oil cylinder 9. The chute 10 is inserted behind the shielding beam 6. The chute telescopic oil cylinder 9 is respectively hinged to the shielding beam 6 and the chute 10, and the telescopic length ΔS is controlled by the chute telescopic oil cylinder 9. The chute telescopic length ΔS and the horizontal swing angle α3 of the shielding beam 6 satisfy the following relationship:

[0058] H - Δh = (S + ΔS)cosα3

[0059] Wherein, H is the support height, Δh is the safety clearance between the top end of the shielding beam 6 and the bearing beam 1 and Δh ≥ 50mm, S is the initial length of the shielding beam 6, and α3 is the horizontal swing angle of the shielding beam 6.

[0060] Further, the isolation and slurry blocking cloth 8 is a five-layer composite structure, including:

[0061] The outer layer is graphene-coated polyester fiber with a thickness of 0.2mm;

[0062] The compressive layer is an aramid fiber woven mesh with a thickness of 0.5mm;

[0063] The isolation layer is a microporous PTFE membrane with a thickness of 0.1mm;

[0064] The strengthening layer is a stainless steel wire mesh with a thickness of 0.3mm;

[0065] The inner layer is a wear-resistant polyurethane coating with a thickness of 0.4mm;

[0066] The total thickness of the isolation and slurry blocking cloth 8 is 1.5mm, and the areal density is 1800g / m 2 , and the burst strength ≥ 1.2MPa. As an embodiment, a slurry isolation method for a caving and backfilling mining net-laying and slurry-blocking support includes the following steps:

[0067] S1. Synchronize the support moving and mesh laying: When the support is moved forward, the isolation net 14 is deployed by an electric drive device, and the isolation net 14 is laid on the upper surface of the lower sub - seam at a rate matching the support moving speed, and is flattened by the rear scraper conveyor 11;

[0068] S2. Coal caving: Control the swing angle cylinder 7 of the shield beam to rotate the shield beam 6, and at the same time retract the ejector plate 10. After the top coal collapses, it is transported out by the rear scraper conveyor 11;

[0069] S3. Slurry blocking: After the coal caving is completed, control the lift cylinder 4 of the shield beam to lower the shield beam 6, deploy the isolation slurry - blocking cloth 8 to a length greater than the sum of the maximum extended lengths of the shield beam 6 and the ejector plate 10, fix the isolation slurry - blocking cloth 8 at the bottom end of the ejector plate 10, and adjust the tension of the isolation slurry - blocking cloth to 50 - 200 N / m;

[0070] S4. Filling and grouting: The tension of the isolation slurry - blocking cloth 8 is monitored in real - time by a PID controller, and the torque of the electric drive device is adjusted. The equation is:

[0071]

[0072] where T is the output torque, e(t) is the deviation between the tension set value and the actual value, K p 、K i 、K d are PID control parameters.

[0073] Furthermore, in step S1, the matching error between the mesh - laying speed and the support - moving speed is less than 3%, and the rotation speed of the rotating shaft 13 is adjusted by a multi - node PID control algorithm.

[0074] Furthermore, the control equation of the multi - node PID control algorithm adopted by the electric drive device of the automatic mesh - laying device is:

[0075]

[0076] where ΔL is the difference between the actual support - moving speed and the set mesh - laying speed, and the difference is less than 3%, K p is the proportionality coefficient, K i is the integral coefficient, K d is the differential coefficient.

[0077] Furthermore, in step S3, the tension of the isolation slurry - blocking cloth 8 is fed back to the PID controller in real - time by tension sensors arranged at the end of the ejector plate 10, the middle of the shield beam 6 and the rotating shaft 13.

[0078] Furthermore, in step S2, the coal - caving process is sequential single - support or group coal - caving, and the rotation angle α3 of the shield beam 6 and the telescopic length ΔS of the ejector plate 10 are dynamically matched to ensure that the coal - caving opening is fully opened.

[0079] 10. According to the slurry partition method of claim 6, after the isolation and slurry-blocking cloth 8 is unfolded in step S3, the lifting cylinder 4 of the shield beam controls the shield beam 6 to rise until the safety clearance Δh between the shield beam and the bearing beam 1 is ≥ 50 mm, forming a continuous slurry-blocking barrier.

[0080] Embodiment 1

[0081] As Figure 1 shown, the embodiment of the present invention discloses a new support for laying a net and blocking slurry in top coal caving filling mining, which can lay an isolation net 14 on the upper surface of the lower sectional coal seam in horizontal fully mechanized top coal caving mining and prevent the slurry from overflowing into the inside of the support and the working face during the filling process, including a top coal caving hydraulic support, an automatic net laying device and an isolation and slurry-blocking device.

[0082] The top coal caving hydraulic support includes a reverse four-link support main body, a split shield beam 6 mechanism and a coal discharging mechanism. The reverse four-link support main body includes a bearing beam 1, a reverse four-link mechanism 3, two groups of hydraulic columns and a base 16. The reverse four-link mechanism 3 is hinged to the bearing beam 1, and the hinge angle is designed to be 15° to 45°. As an embodiment, the two groups of hydraulic columns are two front columns 2 and two rear columns 15 respectively, which are hinged to the bearing beam 1 and the base 16 respectively. The split shield beam 6 mechanism includes a shield beam 6, a shield beam lifting column 5, a shield beam 6 lifting cylinder 4 and a shield beam swing angle cylinder 7. The lower end of the shield beam lifting column 5 is fixed to the base 16, and the upper end is hinged to the shield beam 6. There are 2 shield beam 6 lifting cylinders 4 and 2 shield beam swing angle cylinders 7 respectively, which are hinged to the shield beam 6 and the base 16 respectively. The split shield beam 6 mechanism is a detachable and adjustable structure as a whole, and adapts to different mining conditions by adjusting the lengths of the shield beam 6 and the telescopic beam. The coal discharging mechanism includes a chute 10 and a chute 10 telescopic cylinder 9. The chute 10 is inserted behind the shield beam 6, and the chute telescopic cylinder 9 is hinged to the shield beam 6 and the chute 10 respectively, and can extend and retract a certain length through the chute 10 telescopic cylinder 9.

[0083] The reverse four-link mechanism 3 controls the lifting of the height of the top coal caving hydraulic support. During the lifting process, there is a certain offset in the horizontal direction of the top coal caving hydraulic support, resulting in interference between the bearing beam 1 and the shield beam 6. The shield beam 6 lifting cylinder 4 should dynamically adjust the height of the shield beam lifting column 5 according to the height H of the top coal caving hydraulic support to ensure that the top end of the shield beam 6 always maintains a safety clearance of more than Δh = 50 mm from the bearing beam 1 to avoid interference. As Figure 2 shown, the equation for the height H of the top coal caving hydraulic support is:

[0084]

[0085] The shield beam 6 realizes the horizontal swing angle through the shield beam swing angle cylinder 7, and the chute 10 extends and retracts through the chute 10 telescopic cylinder 9. The geometric relationship between the shield beam swing angle α3 and the telescopic length ΔS of the chute 10 is:

[0086] H - Δh = (S + ΔS)cosα3

[0087] H - Δh = (S + ΔS)cosα3

[0088] Wherein, S is the length of the shield beam 6.

[0089] The automatic mesh laying device includes a separating net 14, a fixing pin 12, a rotating shaft 13, and an electric driving device. The separating net 14 is made of graphene-coated polyester fiber, wound around the rotating shaft 13. The rotating shaft 13 is fixed below the shield beam 6 of the top coal caving hydraulic support through the fixing pin 12, and the separating net 14 can be rotated and unfolded by the electric driving device. The electric driving device adopts a multi-node PID control algorithm, with a control response time < 50 ms and a speed matching error < 3%:

[0090]

[0091] Wherein, ΔL = actual support moving speed - set mesh laying speed, and the specific parameter values of Kp, Ki, and Kd need to be optimized through on-site debugging.

[0092] The separating slurry retaining device includes a separating slurry retaining cloth 8, a fixing pin 12, a rotating shaft 13, and an electric driving device. The anti-leakage efficiency tests of the slurry retaining cloth 8 made of three different materials are carried out under the test conditions of a pressure of 0.5 MPa and a duration of 2 hours, and the results are shown in Table 1.

[0093] Table 1

[0094]

[0095] The test results show that the graphene-coated polyester fiber slurry retaining cloth 8 has the most excellent anti-leakage performance, and the leakage amount is only 2.5% of that of the ordinary nylon cloth, fully meeting the requirements of the high-pressure filling working condition.

[0096] Preferably, the separating slurry retaining cloth 8 adopts a five-layer composite structure: ① outer layer: graphene-coated polyester fiber (thickness 0.2 mm); ② compressive layer: aramid fiber woven mesh (thickness 0.5 mm); ③ isolation layer: microporous PTFE membrane (thickness 0.1 mm); ④ strengthening layer: stainless steel wire mesh (thickness 0.3 mm); ⑤ inner layer: wear-resistant polyurethane coating (thickness 0.4 mm), with a total thickness of 1.5 mm and a surface density of 1800 g / m 2 , and the blasting strength ≥ 1.2 MPa. The separating slurry retaining cloth 8 is laid flat on the shield beam 6, one end is wound around the rotating shaft 13, and the rotating shaft 13 is fixed below the shield beam 6 of the top coal caving hydraulic support through the fixing pin 12. The separating net 14 can be rotated and unfolded or recovered by the electric driving device. The electric driving device is arranged at the end of the plug board 10, the middle of the shield beam 6, and the rotating shaft 13, and can adjust the laying position, length, and tension of the slurry retaining cloth 8.

[0097] Each device cooperates with each other to perform process actions, complete the technological processes such as coal caving, net laying, and slurry blocking in the horizontal sectional fully-mechanized caving and backfilling mining technology, and plays a role in controlling the stability of the backfill body. As Figure 5 shown, as an embodiment, a slurry blocking method for a support for net laying and slurry blocking in caving and backfilling mining is as follows:

[0098] In the first step, after the coal mining process is completed, the support is moved. The net laying process is synchronized with the support moving process. When the caving hydraulic support moves forward, the rotating shaft 13 rotates through an electric driving device, so that the isolation net 14 is automatically unfolded and laid on the upper surface of the lower sectional coal seam. When the subsequent scraper conveyor 11 at the rear is pulled, the isolation net 14 is flattened, and the upper surface of the lower sectional coal seam is completely covered as the working face advances.

[0099] In the second step, the coal caving process is carried out after the coal mining and support moving processes. The swing angle cylinder 7 of the caving hydraulic support and the telescopic cylinder 9 of the insertion plate 10 cooperate to perform actions to complete the processes of the swing of the shield beam 6 and the retraction of the insertion plate 10. The top coal collapses and is transported out of the working face through the rear scraper conveyor 11. After the top coal is completely discharged, the swing angle cylinder 7 of the shield beam and the telescopic cylinder 9 of the insertion plate 10 cooperate to perform actions to complete the processes of the outward expansion of the shield beam 6 and the extension of the insertion plate 10, and the conveyor push-pull cylinder retracts the rear scraper conveyor 11. The coal caving process of the entire working face is completed by sequentially caving coal from single supports or groups of supports of the caving hydraulic support.

[0100] In the third step, the length is greater than the sum of the length of the shield beam 6 and the maximum extension length of the insertion plate 10. By controlling the strokes of the swing angle cylinder 7 of the shield beam and the telescopic cylinder 9 of the insertion plate 10, the bottom end of the insertion plate 10 fixes the slurry blocking cloth 8, as Figure 4 shown. The electric driving device adjusts the tension of the slurry blocking cloth 8 according to the goaf shape, and the range is 50 - 200 N / m. A tension sensor is set to monitor the force on the slurry blocking cloth 8 in real time and feedback it to the PID controller to adjust the rotation speed and torque of the electric driving device:

[0101]

[0102] where T is the output torque and e(t) is the deviation between the tension set value and the actual value. The slurry blocking cloth 8 completely covers and closely adheres to the shield beam 6, and the lifting cylinder 4 of the shield beam 6 controls the shield beam 6 to rise and block, ensuring that the slurry can be prevented from flowing into the support and the working face.

[0103] In the fourth step, the filling grouting process is carried out. After completion, coal mining is carried out to start the next process cycle. It should be noted that in this article, relational terms such as first and second are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any actual relationship or order between these entities or operations. Moreover, the terms "including", "comprising" or any other variant thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements not only includes those elements, but also includes other elements not expressly listed, or further includes elements inherent to such process, method, article or device.

[0104] The above is only the preferred embodiment of the present invention. It should be pointed out that for those of ordinary skill in the art, without departing from the technical principle of the present invention, several improvements and deformations can be made, and these improvements and deformations should also be regarded as the protection scope of the present invention.

Claims

1. A reticulated slurry retaining support for top coal caving filling mining, characterized in that, Comprising: A top-coal caving hydraulic support, including an inverted four-bar support main body, a split shield beam mechanism, and a coal discharging mechanism; The inverted four-bar support main body is located at the front of the top-coal caving hydraulic support and is hinged to the split shield beam mechanism through a base (16). The split shield beam mechanism is located at the rear of the top-coal caving hydraulic support, and its shield beam (6) is connected to the base (16) through a shield beam lifting oil cylinder (4) and a shield beam swing angle oil cylinder (7); the coal discharging mechanism's platen (10) is inserted into the interior of the shield beam (6) and is driven to expand and contract by a platen telescopic oil cylinder (9); An automatic net laying device, including an isolation net (14), a fixed pin (12), a rotating shaft (13), and an electric drive device. The rotating shaft (13) is installed below the shield beam (6) through the fixed pin (12), and the isolation net (14) is wound around the rotating shaft (13) and is unfolded through the electric drive device; An isolation slurry blocking device, including an isolation slurry blocking cloth (8), a fixed pin (12), a rotating shaft (13), and an electric drive device. The rotating shaft (13) is fixed below the shield beam (6) through the fixed pin (12), and one end of the isolation slurry blocking cloth (8) is wound around the rotating shaft (13) and is unfolded through the electric drive device.

2. The caving filling mining net-laying slurry retaining support according to claim 1, characterized in that, The inverted four-bar support main body includes a bearing beam (1), an inverted four-bar mechanism (3), two groups of hydraulic columns, and a base (16). The inverted four-bar mechanism (3) is hinged to the bearing beam (1), and the hinge angle is 15° to 45°. The two groups of hydraulic columns include a front column (2) and a rear column (15), which are respectively hinged to the bearing beam (1) and the base (16).

3. The caving filling mining net-laying slurry retaining support according to claim 1, wherein, The split shield beam mechanism includes a shield beam (6), a shield beam lifting column (5), a shield beam lifting oil cylinder (4), and a shield beam swing angle oil cylinder (7). The lower end of the shield beam lifting column (5) is fixed to the base (16), and the upper end is hinged to the shield beam (6). The shield beam lifting oil cylinder (4) and the shield beam swing angle oil cylinder (7) are respectively hinged to the shield beam (6) and the base (16), and the length of the shield beam (6) is adjustable to adapt to different mining conditions.

4. The caving filling mining net-laying and slurry-blocking support according to claim 3, characterized in that, The coal discharging mechanism includes a platen (10) and a platen telescopic oil cylinder (9). The platen (10) is inserted into the shield beam (6) at the rear. The platen telescopic oil cylinder (9) is respectively hinged to the shield beam (6) and the platen (10), and the telescopic length ΔS is controlled by the platen telescopic oil cylinder (9). The platen telescopic length ΔS and the shield beam swing angle α3 satisfy the following relationship: H - Δh = (S + ΔS)cosα3 Wherein, H is the support height, Δh is the safety clearance between the top of the shield beam (6) and the bearing beam (1) and Δh ≥ 50 mm, S is the initial length of the shield beam (6), and α3 is the horizontal swing angle of the shield beam (6).

5. The caving and backfilling mining net-laying and slurry-blocking support according to claim 1, wherein, The isolation slurry blocking cloth (8) is a five-layer composite structure, including: The outer layer is graphene-coated polyester fiber with a thickness of 0.2 mm; The compressive layer is an aramid fiber woven net with a thickness of 0.5 mm; The isolation layer is a microporous PTFE membrane with a thickness of 0.1 mm; The reinforcement layer is a stainless steel wire mesh with a thickness of 0.3 mm; The inner layer is a wear-resistant polyurethane coating with a thickness of 0.4 mm; The total thickness of the isolation slurry blocking cloth (8) is 1.5 mm, and the surface density is 1800 g / m 2 , and the bursting strength ≥ 1.2 MPa.

6. A slurry partition method for the gob-side entry packing mining with top-coal caving and net-laying support according to claim 1, characterized in that, Including the following steps: S1. Synchronize support moving and net laying: When the support is moved forward, the isolation net (14) is deployed by an electric drive device and laid on the upper surface of the lower coal seam section at a rate matching the support moving speed, and is flattened by the rear scraper conveyor (11). S2. Coal caving: Control the swing angle cylinder (7) of the shield beam to rotate the shield beam (6), and at the same time retract the insertion plate (10). After the top coal collapses, it is transported out by the rear scraper conveyor (11). S3. Slurry blocking: After coal caving is completed, control the lift cylinder (4) of the shield beam to lower the shield beam (6), deploy the isolation slurry blocking cloth (8) to a length greater than the sum of the maximum extended lengths of the shield beam (6) and the insertion plate (10), fix the isolation slurry blocking cloth (8) at the bottom end of the insertion plate (10), and adjust the tension of the isolation slurry blocking cloth to 50 - 200 N / m. S4. Filling and grouting: The tension of the isolation slurry blocking cloth (8) is monitored in real time by a PID controller, and the torque of the electric drive device is adjusted. The equation is: Among them, T is the output torque, e(t) is the deviation between the tension set value and the actual value, K p , K i , K d are PID control parameters.

7. The slurry partitioning method according to claim 6, characterized in that, In step S1, the matching error between the net laying speed and the support moving speed is less than 3%. The rotation speed of the rotating shaft (13) is adjusted by a multi-node PID control algorithm. The control equation of the multi-node PID control algorithm adopted by the electric drive device of the automatic net laying device is: where ΔL is the difference between the actual support moving speed and the set net laying speed, and the difference is less than 3%, K p is the proportionality coefficient, K i is the integral coefficient, K d is the differential coefficient.

8. The slurry partition method according to claim 6, wherein, In step S3, the tension of the isolation slurry blocking cloth (8) is fed back to the PID controller in real time by tension sensors arranged at the end of the insertion plate (10), the middle of the shield beam (6), and the rotating shaft (13).

9. The slurry partitioning method according to claim 6, wherein In step S2, the coal caving process is sequential single-frame or group coal caving. The rotation angle α3 of the shield beam (6) and the telescopic length ΔS of the insertion plate (10) are dynamically matched to ensure that the coal caving opening is fully opened.

10. The slurry partition method according to claim 6, characterized in that, After the isolation slurry blocking cloth (8) is deployed in step S3, the lift cylinder (4) of the shield beam controls the shield beam (6) to rise to a safety gap Δh ≥ 50 mm from the load-bearing beam (1) to form a continuous slurry blocking barrier.

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