Extra-large flow reversing valve for coal mine and design method

Abstract

The ultra-large flow reversing valve for the coal mine comprises a left valve sleeve, a piston, a valve element, a valve seat, a clamp, a compression spring and a right valve sleeve, and the left valve sleeve, the piston, the valve element, the valve seat, the clamp and the right valve sleeve are all of a rotary body structure. The left valve sleeve and the right valve sleeve are connected through a hoop, the end of the left valve sleeve is concaved inwards to form a left valve sleeve cavity, the piston is located in the left valve sleeve cavity, one end of the valve element is located in the piston, the other end of the valve element is located in the right valve sleeve, and the valve seat is located at the end of the left valve sleeve and abuts against the inner surface of the left valve sleeve. And the compression spring is sleeved on the valve core and is positioned in the right valve sleeve. A control port and a liquid return port are formed in the left valve sleeve, the axis of the control port is perpendicular to the axis of the left valve sleeve, the control port and the liquid return port are both communicated with a cavity of the left valve sleeve, a liquid inlet is formed in the right valve sleeve, and the liquid inlet is communicated with a gap between the valve element and the right valve sleeve. The valve element is provided with a valve element through hole and a working opening, and the axis of the working opening is parallel to the axis of the right valve sleeve.

Description

Technical Field

[0001] The invention belongs to the technical field of coal seam mining, and in particular relates to an ultra-large flow reversing valve for coal mines and a design method thereof. Background Art

[0002] At present, the mining of thick coal seams and extra-thick coal seams mostly uses the top coal caving technology. However, in the actual mining process of coal mines, it is found that top coal caving mining has various problems such as poor roof stability, incomplete coal seam mining, mixing of coal and gangue, and dust pollution. Not only does it pose a great safety risk and environmental pollution, but it also reduces the quality and economic benefits of coal.

[0003] At present, we have successfully developed 8.8-meter and 10-meter ultra-large mining height hydraulic supports, which are used for full-height mining of extra-thick coal seams at one time, improving coal mining efficiency and quality, while ensuring stable support of hydraulic supports. For ultra-large mining height hydraulic supports, since the matching oil cylinder is large in size and has a long stroke, an ultra-large flow and high-pressure electro-hydraulic control reversing valve group is required to realize the support movement control.

[0004] In order to meet the requirements of fluid supply and motion control of ultra-large mining height hydraulic supports, there are currently two solutions, one is to supply fluid by connecting multiple valve core components in parallel, and the other is to supply fluid by connecting a single valve core component. For the parallel control method of multiple valve core components, due to the large number of valve core components, the manufacturing and maintenance costs are high. At the same time, considering the large flow fluctuations in the liquid flow process, the synchronous control of the valve core components is difficult and the overflow loss is large. For the single valve core component control method, due to the large flow rate and high pressure of the valve core component, the valve core component needs to withstand huge impact force during movement, which is prone to leakage, damage and low service life, and the maintenance cost is relatively high. Therefore, the existing ultra-large flow reversing valves for coal mines have obvious deficiencies in impact resistance, sealing performance and service life, and cannot meet the needs of modern coal mining. Summary of the invention

[0005] The purpose of the present invention is to solve the above problems and provide an ultra-large flow reversing valve for coal mines with good sealing, long service life, low manufacturing cost and the ability to withstand large impact force and a design method.

[0006] In order to solve the above technical problems, the technical solution of the present invention is: a super-large flow reversing valve for coal mines, comprising a left valve sleeve, a piston, a valve core, a valve seat, a clamp, a compression spring and a right valve sleeve, wherein the left valve sleeve, the piston, the valve core, the valve seat, the clamp and the right valve sleeve are all revolving body structures; the left valve sleeve and the right valve sleeve are connected by a clamp, the end of the left valve sleeve is concave to form a left valve sleeve cavity, the piston is located in the left valve sleeve cavity, one end of the valve core is located inside the piston, the other end of the valve core is located in the right valve sleeve, the valve seat is located at the end of the left valve sleeve and abuts against the inner surface of the left valve sleeve, and the compression spring sleeve is arranged in the left valve sleeve cavity. The valve core is located on the right valve sleeve; a control port and a liquid return port are provided on the left valve sleeve, the axis of the control port is perpendicular to the axis of the left valve sleeve, the control port and the liquid return port are both connected to the left valve sleeve cavity, when the piston is located at the bottom end inside the left valve sleeve, the control port and the liquid return port are respectively located at both ends of the piston, the angle between the axis of the liquid return port and the axis of the left valve sleeve is less than ninety degrees, a liquid inlet is provided on the right valve sleeve, the liquid inlet is connected to the gap between the valve core and the right valve sleeve; a valve core through hole and a working port are provided on the valve core, the valve core through hole is connected to the working port, and the axis of the working port is parallel to the axis of the right valve sleeve.

[0007] Preferably, a left valve sleeve groove is provided at the end of the left valve sleeve, and a right valve sleeve groove is provided at the end of the right valve sleeve. The cross-section of the clamp is a "concave"-shaped structure, and the two ends of the clamp are respectively located in the left valve sleeve groove and the right valve sleeve groove, thereby connecting the left valve sleeve and the right valve sleeve.

[0008] Preferably, the edge of the inner ring of the valve seat is an inclined structure, a valve seat groove is provided on the outer ring of the valve seat, a valve seat sealing ring is provided in the valve seat groove, the inclination of one side of the inner ring of the valve seat matches the inclination of the piston end, and the inclination of the other side of the inner ring of the valve seat matches the valve core.

[0009] Preferably, a valve core protrusion is provided on the valve core, and the cross-section of the valve core protrusion is a trapezoidal structure. The end of the compression spring abuts against the valve core protrusion, and the other end of the compression spring abuts against the right valve sleeve.

[0010] The present invention also discloses a design method of an ultra-large flow reversing valve for coal mines, comprising the following steps:

[0011] S1. Design input, high water-based reversing valve flow rate, calculation of key position flow area, component material selection, wall thickness design;

[0012] S2. Conduct mechanical performance analysis and sealing form analysis, and then confirm the key structural dimensions and control port dimensions;

[0013] S3. Establish a mathematical simulation model to conduct structural strength analysis and flow field analysis;

[0014] S4. Determine materials and complete principle design;

[0015] S5. Test verification, finalize the structure based on the test data.

[0016] Further: the flow area at the key position is calculated in S1 according to the pressure-flow characteristic calculation formula of the valve port: The valve core assembly is affected by various factors such as the flow channel structure, flow area and friction resistance during movement. In order to ensure the response speed of the hydraulic support, the pressure loss of the valve core assembly must be reduced as much as possible; according to the flow rate calculation formula: The flow rate calculation formula of the reversing valve can be calculated. Therefore, according to the pressure-flow characteristics of the reversing valve and the design requirements of the mining reversing valve, the flow area Ai of key positions such as the liquid inlet P, the working port A, and the return port T can be preliminarily determined; combined with the valve port flow formula of the cone valve, the valve core stroke calculation formula can be obtained as follows: Therefore, combined with the flow and pressure loss requirements of the valve core, the valve core x of the reversing valve can be calculated. i The size of the stroke.

[0017] Furthermore, the material selection of the components in S1 includes the material selection of the piston, valve core and valve seat. According to the minimum flow area of ​​the valve core assembly and the valve core stroke size, high-strength stainless steel material can be preliminarily selected as the base material of the piston, valve core and valve seat; according to the mechanical properties of the base material, and taking into account the current miniaturization and lightweight design requirements of the valves used in hydraulic supports, it is necessary to design the wall thickness of the valve core assembly in combination with the operating conditions, and preliminarily infer whether the current material meets the design requirements; if the material performance does not meet the requirements, a secondary selection is made based on the current material data.

[0018] Furthermore, the wall thickness design in S1 is based on the allowable stress of the material, and the wall thickness of the part t≥P*D / 2[σ], wherein: P is the working pressure inside the valve core assembly, D is the inner diameter of the flow hole of the valve core assembly, and [σ] is the allowable stress of the material; after the wall thickness calculation is completed, the sealing structure and sealing method are combined to ensure that the sealing performance of the valve core assembly meets the design requirements.

[0019] Furthermore, the mathematical simulation model is established in S3 after the wall thickness of the valve core assembly is calculated and the sealing method is determined, and then the mathematical simulation model is established according to the structural model and principle analysis, and then assigned values ​​according to the design calculation results; after the assignment is completed, a simulation run is performed to verify the correctness of the valve core assembly simulation model. If the simulation results are inconsistent with the actual design calculation results, the design calculation results are compared with the simulation data model.

[0020] Furthermore, after the verification of the mathematical simulation model in S3 is completed, it is necessary to analyze the flow rate under different working conditions, the maximum flow rate inside the valve core assembly, the maximum flow rate position, etc., and then adjust the valve core displacement and the flow position structure accordingly according to the pressure-flow characteristics to reduce the pressure loss of the working medium when the valve core assembly moves, thereby ensuring the smooth and rapid operation of the hydraulic support.

[0021] The beneficial effects of the present invention are:

[0022] 1. The ultra-large flow reversing valve for coal mines provided by the present invention can withstand huge impact force under ultra-large flow and ultra-high pressure, including reversing impact and resetting impact, and is not easy to be damaged.

[0023] 2. Problems with existing reversing valves include: poor sealing performance. The sealing position of the existing reversing valve is prone to damage and deformation, and leakage is prone to occur, which affects the stable support and safe production of the comprehensive mining working face. The service life of the existing reversing valve is limited and can usually only be used for a few thousand times, and the maintenance cost is high. The present invention can overcome the above-mentioned problems of the existing reversing valve.

[0024] 3. The present invention is based on the use requirements of high water-based hydraulic support valves for ultra-large flow and ultra-high pressure. It takes flow rate design as the basis, and through 3D modeling, digital analysis and high-strength material selection, proposes a design method for ultra-large flow reversing valves for coal mines, which improves the design efficiency and product quality of valves for hydraulic supports, while ensuring the impact resistance, sealing performance and service life of high water-based valves.

[0025] 4. The present invention combines the theoretical design calculation results of the ultra-large flow reversing valve for mining, takes the flow rate design as the starting point, and determines the key structural dimensions of the reversing valve in sequence to ensure that the reversing valve meets the pressure-flow characteristic requirements. Through mathematical simulation models, material mechanics and dynamic simulation analysis, the working principle, structural dimensions, force magnitude, flow rate and material selection are analyzed in sequence. The structural dimensions, materials, wall thickness and other parameters of the reversing valve are determined through continuous iteration, which greatly improves the design efficiency of the reversing valve. Through the theory-experiment-theory design method, the design scheme of the product is continuously iterated, and finally a fixed design method is formed, which greatly improves the accuracy and reliability of product design. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] Figure 1 It is a structural schematic diagram of a super large flow reversing valve for coal mines of the present invention;

[0027] Figure 2 It is a flow chart of the steps of a design method of a super large flow reversing valve for coal mines of the present invention;

[0028] Figure 3It is a schematic diagram of the flow area and stroke calculation process of the reversing valve of the present invention;

[0029] Figure 4 It is a schematic diagram of the calculation process of mechanical properties of materials and structures of the present invention;

[0030] Figure 5 It is a schematic diagram of the structure of the mathematical simulation model of the valve core assembly of the present invention;

[0031] Figure 6 Schematic diagram of the flow rate simulation analysis result of the valve core assembly of the present invention;

[0032] Figure 7 This is a schematic diagram of the simulation analysis results of the valve core displacement of the valve core assembly of the present invention.

[0033] Figure 8 It is a schematic diagram of the analysis process of the mathematical simulation model of the present invention;

[0034] Fig. 9 It is a schematic diagram of the structural analysis process of the present invention in combination with a mathematical simulation model;

[0035] Fig.10 It is a schematic diagram of the static simulation analysis results of the valve seat deformation size of the present invention;

[0036] Fig.11 It is a schematic diagram of the static simulation analysis results of the valve seat stress size of the present invention;

[0037] Fig.12 It is a schematic diagram of the simulation analysis result of the flow field pressure inside the valve core assembly of the present invention;

[0038] Fig.13 It is a schematic diagram of the flow field velocity simulation analysis results inside the valve core assembly of the present invention.

[0039] Explanation of the reference numerals: 101, left valve sleeve; 102, piston; 103, valve core; 104, valve seat; 105, clamp; 106, compression spring; 107, right valve sleeve; A, working port; K, control port; P, liquid inlet; T, liquid return port. DETAILED DESCRIPTION

[0040] The present invention will be further described below in conjunction with the accompanying drawings and specific embodiments:

[0041] like Figures 1 to 13As shown, the present invention provides a super large flow reversing valve for coal mines, including a left valve sleeve 101, a piston 102, a valve core 103, a valve seat 104, a clamp 105, a compression spring 106 and a right valve sleeve 107. The left valve sleeve 101, the piston 102, the valve core 103, the valve seat 104, the clamp 105 and the right valve sleeve are all revolving structures. The left valve sleeve 101 and the right valve sleeve are connected by the clamp 105. The end of the left valve sleeve 101 is concave to form a left valve sleeve cavity. The piston 102 is located in the left valve sleeve cavity. One end of the valve core 103 is located inside the piston 102, and the other end of the valve core 103 is located in the right valve sleeve. The valve seat 104 is located at the end of the left valve sleeve 101 and abuts against the inner surface of the left valve sleeve 101. The compression spring 106 is sleeved on the valve core 103 and located inside the right valve sleeve. The left valve sleeve 101 is provided with a control port K and a liquid return port T, the axis of the control port K is perpendicular to the axis of the left valve sleeve 101, and the control port K and the liquid return port T are both connected to the left valve sleeve cavity. When the piston 102 is located at the bottom of the left valve sleeve 101, the control port K and the liquid return port T are respectively located at the two ends of the piston 102, and the angle between the axis of the liquid return port T and the axis of the left valve sleeve 101 is less than ninety degrees. The right valve sleeve is provided with a liquid inlet P, which is connected to the gap between the valve core 103 and the right valve sleeve. The valve core 103 is provided with a valve core through hole and a working port A, the valve core through hole is connected to the working port A, and the axis of the working port A is parallel to the axis of the right valve sleeve.

[0042] A left valve sleeve groove is provided at the end of the left valve sleeve 101, and a right valve sleeve groove is provided at the end of the right valve sleeve. The cross-section of the clamp 105 is a "concave"-shaped structure, and the two ends of the clamp 105 are respectively located in the left valve sleeve groove and the right valve sleeve groove, thereby connecting the left valve sleeve 101 and the right valve sleeve.

[0043] The edge of the inner ring of the valve seat 104 is an inclined structure, a valve seat groove is provided on the outer ring of the valve seat 104, a valve seat sealing ring is provided in the valve seat groove, the inclination of one side of the inner ring of the valve seat 104 matches the inclination of the end of the piston 102, and the inclination of the other side of the inner ring of the valve seat 104 matches the valve core 103.

[0044] The valve seat 104 is provided with an annular valve seat groove, in which a valve seat sealing ring is provided, and the valve seat 104 is located at the end of the left valve sleeve 101. The left valve sleeve cavity is a stepped structure, one end of the valve seat 104 abuts against the stepped structure of the left valve sleeve cavity, and the other end of the valve seat 104 abuts against the end of the right valve sleeve.

[0045] The valve core 103 is provided with a valve core protrusion, the cross section of which is a trapezoidal structure, the end of the compression spring 106 abuts against the valve core protrusion, and the other end of the compression spring 106 abuts against the right valve sleeve. The valve core 103 squeezes the compression spring 106 during the movement, and the compression spring 106 pushes the valve core 103 to move during the recovery process.

[0046] In this embodiment, the cross-section of the valve core through hole is an elliptical structure, and the valve core through holes are distributed on the valve core 103 in a ring array.

[0047] A ring-shaped right valve sleeve end groove is arranged at the end of the right valve sleeve, and a right valve sleeve end sealing ring is sleeved in the right valve sleeve end groove.

[0048] When the present invention is in the original state, the control port K has no control pressure, that is, the control port K does not pass hydraulic oil. At this time, the working port A and the liquid inlet P are disconnected, and the working port A is connected to the liquid return port T. The working port A is connected to the oil inlet of the existing hydraulic equipment. When the corresponding reversing action is required, the control port K has control pressure, that is, the corresponding hydraulic oil is passed, and the piston 102, the valve core 103 and the compression spring 106 are pushed to the right in turn. At this time, the working port A is disconnected from the liquid return port T, and the working port A is connected to the liquid inlet P to achieve the corresponding action. After the corresponding action of the working port A is completed, the control port K has no control pressure, and the piston 102, the valve core 103 and the compression spring 106 move rapidly to the left under the combined force. At this time, the working port A is disconnected from the liquid inlet P and connected to the liquid return port T to stabilize the oil cylinder of the existing hydraulic equipment. In this embodiment, the existing hydraulic equipment includes a hydraulic support.

[0049] The present invention also discloses a design method of an ultra-large flow reversing valve for coal mines, comprising the following steps:

[0050] S1. Design input, high water-based reversing valve flow rate, calculation of key position flow area, component material selection, and wall thickness design.

[0051] The design input includes the parameters of nominal pressure and nominal flow, the flow rate of the high water-based reversing valve V≤C, and the flow area at the calculated key position is represented by A.

[0052] The calculation formula for calculating the flow area at the key position in S1 is based on the pressure-flow characteristic of the valve port: The valve core assembly is affected by various factors such as the flow channel structure, flow area, and friction resistance during movement. In order to ensure the response speed of the hydraulic support, the pressure loss of the valve core assembly must be reduced as much as possible. According to the flow rate calculation formula: The flow rate calculation formula of the reversing valve can be calculated. Therefore, according to the pressure-flow characteristics of the reversing valve and the design requirements of the mining reversing valve, the flow area Ai of key positions such as the liquid inlet P, the working port A, and the return port T can be preliminarily determined. Combined with the valve port flow formula of the cone valve, the valve core stroke calculation formula can be obtained as follows: Therefore, combined with the flow and pressure loss requirements of the valve core, the valve core x of the reversing valve can be calculated. i The stroke size. Among them, Q is the flow rate, A is the flow area, C dis the valve port flow coefficient, ΔP is the inlet and outlet pressure loss, x is the valve core displacement, C is the flow coefficient, d is the flow hole diameter, α is the valve port jet angle, and ρ is the working medium density.

[0053] The material selection of components in S1 includes the material selection of piston 102, valve core 103 and valve seat 104. According to the minimum flow area of ​​the valve core assembly and the valve core stroke size, high-strength stainless steel material can be preliminarily selected as the base material of piston 102, valve core 103 and valve seat 104; according to the mechanical properties of the base material, and considering the current miniaturization and lightweight design requirements of hydraulic support valves, it is necessary to combine the use conditions of the valve core assembly, design its wall thickness, and preliminarily infer whether the current material meets the design requirements; if the material performance does not meet the requirements, a secondary selection is made based on the current material data.

[0054] The wall thickness design in S1 is based on the allowable stress of the material. The wall thickness of the part t≥P*D / 2[σ], where: P is the working pressure inside the valve core assembly, D is the inner diameter of the flow hole of the valve core assembly, and [σ] is the allowable stress of the material. After the wall thickness calculation is completed, the sealing structure and sealing method are combined to ensure that the sealing performance of the valve core assembly meets the design requirements.

[0055] S2. Conduct mechanical performance analysis and sealing form analysis, and then confirm the key structural dimensions and determine the control port dimensions.

[0056] In step S2, the part material is selected according to the design requirements, and then the mechanical properties are analyzed. If the design requirements are met, the wall thickness design is performed. If the requirements are not met, the part material is reselected. After the wall thickness design meets the requirements, the sealing structure and method are designed and analyzed. After the requirements of miniaturization and lightweight are met, the material is preliminarily set.

[0057] S3. Establish a mathematical simulation model to conduct structural strength analysis and flow field analysis.

[0058] In step S3, the mathematical simulation model is established after the wall thickness of the valve core component is calculated and the sealing method is determined. The mathematical simulation model is established according to the structural model and principle analysis, and then it is assigned according to the design calculation results. After the assignment is completed, a simulation run is performed to verify the correctness of the valve core component simulation model. If the simulation result is inconsistent with the actual design calculation result, the design calculation result is compared with the simulation data model.

[0059] After the mathematical simulation model verification is completed in step S3, it is necessary to analyze the flow rate under different working conditions, as well as the maximum flow rate inside the valve core assembly, the maximum flow rate position, etc., and then adjust the valve core displacement and the flow position structure accordingly according to the pressure-flow characteristics to reduce the pressure loss of the working medium when the valve core assembly moves, so as to ensure the smooth and rapid operation of the hydraulic support.

[0060] By analyzing the force at various positions of the valve core assembly under different pressures, such as the force between the piston 102 and the valve seat 104, and between the valve core 103 and the valve seat 104 during switching / resetting, and then adjusting the control port, sealing position, valve core stroke, flow area, overall size, etc. according to the force, it is ensured that the valve core assembly will not have problems such as back pressure safety and excessive local force during use.

[0061] Combined with the analysis results of design calculations and mathematical simulation models, the force magnitude of each component position of the valve core assembly can be basically determined. Therefore, it is necessary to perform static analysis of the force at each key position to ensure that the product will not suffer structural damage under high pressure.

[0062] Taking into account the strength, stiffness and durability of the material, as well as the analysis results of the mathematical simulation model, the force analysis of the piston 102, valve seat 103 and valve core 104 at different positions and the collision analysis when the valve core assembly switches state are carried out to ensure the sealing performance and durability of the parts under working conditions.

[0063] Since the working medium is affected by various factors such as structural mutations and dimensional changes during movement, eddy currents will appear inside the valve core assembly and the flow rate will change dramatically at the moment of opening and closing, resulting in radial unbalanced force problems when the piston 102 and the valve core 104 move, causing various problems such as the valve core assembly getting stuck. Therefore, it is necessary to analyze the flow rate, pressure and temperature distribution inside the flow field when the valve core assembly is opened, so as to minimize the influence of the radial unbalanced force on the valve core assembly.

[0064] After the structural model is determined, a statics simulation model is established and a statics simulation analysis is performed. After the requirements are met, a collision simulation model is established and then a collision simulation analysis is performed. After the collision simulation analysis meets the requirements, a flow field simulation model is established and then a flow field simulation analysis is performed. After the requirements are met, a fluid-solid bidirectional coupling simulation model is established and a fluid-solid coupling simulation analysis is performed to complete the structural strength analysis.

[0065] S4. Determine materials and complete principle design.

[0066] S5. Test verification, finalize the structure based on the test data.

[0067] Combined with the working principle of the valve core assembly, the force analysis results of the parts in different states and the flow characteristics of the working medium, the overall situation of the valve core assembly in the intermediate position, opening and closing moments, and reversing position working states is analyzed, and the structure of the valve core assembly is comprehensively analyzed to ensure the performance of the valve core assembly in actual working conditions.

[0068] The main function of the flow rate design in the present invention is to ensure that the valve core assembly will not have excessive overflow loss, pressure reduction, reversing, reset impact, etc. at the moment of opening and closing, and to ensure that the valve core assembly is in a stable supply of liquid. The purpose of selecting parts materials is to ensure that the overall design of the valve core assembly meets the requirements of miniaturization and lightweight design, and at the same time provide a reference for subsequent wall thickness calculation and structural strength analysis. The purpose of selecting the sealing form is to consider the influence of various factors such as the sealing width, sealing height and pressure action of the valve core assembly. If the sealing position is too stressed, the service life and sealing performance of the valve core assembly cannot meet the actual use requirements of the coal mine, which greatly increases the maintenance difficulty and reliability of the product. The role of establishing a mathematical simulation model is to verify the principle, ensure that the valve core assembly meets the design requirements under different conditions, such as: flow rate, pressure loss, back pressure safety and other design requirements, and ensure that the valve core assembly can act according to the control instructions under different working conditions. Finally, the rationality of the flow rate design, material selection, mathematical model, parameter setting and analysis data can be verified by combining the test method. At the same time, the mathematical model can be continuously iterated and optimized according to the test data, and finally the stable design of the large flow reversing valve is completed, the design cycle is shortened, and the reliability of the product is improved.

[0069] Those skilled in the art will appreciate that the embodiments described herein are intended to help readers understand the principles of the present invention, and should be understood that the protection scope of the present invention is not limited to such specific statements and embodiments. Those skilled in the art can make various other specific variations and combinations that do not deviate from the essence of the present invention based on the technical revelations disclosed by the present invention, and these variations and combinations are still within the protection scope of the present invention.

Claims

1. A super large flow reversing valve for coal mines, characterized by: The invention comprises a left valve sleeve (101), a piston (102), a valve core (103), a valve seat (104), a clamp (105), a compression spring (106) and a right valve sleeve (107); the left valve sleeve (101), the piston (102), the valve core (103), the valve seat (104), the clamp (105) and the right valve sleeve (107) are all of a rotating body structure; the left valve sleeve (101) and the right valve sleeve (107) are connected by a clamp ( The left valve sleeve (105) is connected to the right valve sleeve (107), the end of the left valve sleeve (101) is concave to form a left valve sleeve cavity, the piston (102) is located in the left valve sleeve cavity, one end of the valve core (103) is located inside the piston (102), the other end of the valve core (103) is located in the right valve sleeve (107), the valve seat (104) is located at the end of the left valve sleeve (101) and abuts against the inner surface of the left valve sleeve (101), and the compression spring (106) is sleeved on the valve sleeve. The left valve sleeve (101) is provided with a control port (K) and a liquid return port (T), the axis of the control port (K) is perpendicular to the axis of the left valve sleeve (101), the control port (K) and the liquid return port (T) are both connected to the left valve sleeve cavity, and when the piston (102) is located at the bottom end of the left valve sleeve (101), the control port (K) and the liquid return port (T) are respectively located at the piston (102) and the liquid return port (T). ), the angle between the axis of the liquid return port (T) and the axis of the left valve sleeve (101) is less than ninety degrees, the right valve sleeve (107) is provided with a liquid inlet (P), and the liquid inlet (P) is connected to the gap between the valve core (103) and the right valve sleeve; the valve core (103) is provided with a valve core through hole and a working port (A), the valve core through hole is connected to the working port (A), and the axis of the working port (A) is parallel to the axis of the right valve sleeve (107).

2. The ultra-large flow reversing valve for coal mines according to claim 1 is characterized in that: The end of the left valve sleeve (101) is provided with a left valve sleeve groove, and the end of the right valve sleeve (107) is provided with a right valve sleeve groove. The cross section of the clamp (105) is a "concave"-shaped structure. The two ends of the clamp (105) are respectively located in the left valve sleeve groove and the right valve sleeve groove, thereby connecting the left valve sleeve (101) and the right valve sleeve (107).

3. The ultra-large flow reversing valve for coal mine according to claim 1 is characterized in that: The edge of the inner ring of the valve seat (104) is an inclined structure, a valve seat groove is provided on the outer ring of the valve seat (104), a valve seat sealing ring is provided in the valve seat groove, the inclination of one side of the inner ring of the valve seat (104) matches the inclination of the end of the piston (102), and the inclination of the other side of the inner ring of the valve seat (104) matches the valve core (103).

4. The ultra-large flow reversing valve for coal mine according to claim 1 is characterized in that: The valve core (103) is provided with a valve core protrusion, the cross section of which is a trapezoidal structure. The end of the compression spring (106) abuts against the valve core protrusion, and the other end of the compression spring (106) abuts against the right valve sleeve (107).

5. A design method for a super large flow reversing valve for coal mines, characterized in that: The following steps are involved: S1. Design input, high water-based reversing valve flow rate, calculation of key position flow area, component material selection, wall thickness design; S2. Conduct mechanical performance analysis and sealing form analysis, and then confirm the key structural dimensions and control port dimensions; S3. Establish a mathematical simulation model to conduct structural strength analysis and flow field analysis; S4. Determine materials and complete principle design; S5. Test verification, finalize the structure based on the test data.

6. The design method of a super large flow reversing valve for coal mines according to claim 5 is characterized in that: The calculation formula for calculating the flow area at the key position in S1 is based on the pressure-flow characteristic of the valve port: The valve core assembly is affected by various factors such as the flow channel structure, flow area and friction resistance during movement. In order to ensure the response speed of the hydraulic support, the pressure loss of the valve core assembly must be reduced as much as possible; according to the flow rate calculation formula: The flow rate calculation formula of the reversing valve can be calculated. Therefore, according to the pressure-flow characteristics of the reversing valve and the design requirements of the mining reversing valve, the flow area Ai of key positions such as the liquid inlet P, the working port A, and the return port T can be preliminarily determined; combined with the valve port flow formula of the cone valve, the valve core stroke calculation formula can be obtained as follows: Therefore, combined with the flow and pressure loss requirements of the valve core, the valve core x of the reversing valve can be calculated. i The size of the stroke.

7. The method for designing a super-large flow reversing valve for coal mines according to claim 5, characterized in that: The material selection of the components in S1 includes the material selection of the piston (102), the valve core (103) and the valve seat (104). According to the minimum flow area of ​​the valve core assembly and the valve core stroke size, a high-strength stainless steel material can be preliminarily selected as the base material of the piston (102), the valve core (103) and the valve seat (104). According to the mechanical properties of the base material and considering the current design requirements of miniaturization and lightweight of the valve for the hydraulic support, it is necessary to design the wall thickness of the valve core assembly in combination with the use conditions of the valve core assembly to preliminarily infer whether the current material meets the design requirements. If the material performance does not meet the requirements, a secondary selection will be made based on the current material data.

8. The method for designing a super-large flow reversing valve for coal mines according to claim 5, characterized in that: The wall thickness design in S1 is based on the allowable stress of the material. The wall thickness of the part t≥P*D / 2[σ], where: P is the working pressure inside the valve core assembly, D is the inner diameter of the flow hole of the valve core assembly, and [σ] is the allowable stress of the material. After the wall thickness calculation is completed, the sealing structure and sealing method are combined to ensure that the sealing performance of the valve core assembly meets the design requirements.

9. The method for designing a super-large flow reversing valve for coal mines according to claim 5, characterized in that: The mathematical simulation model is established in S3 after the wall thickness of the valve core component is calculated and the sealing method is determined, and then the mathematical simulation model is established according to the structural model and principle analysis, and then assigned values ​​according to the design calculation results; After the assignment is completed, a simulation run is performed to verify the correctness of the valve core component simulation model. If the simulation results are inconsistent with the actual design calculation results, the design calculation results are compared with the simulation data model.

10. The method for designing a super-large flow reversing valve for coal mines according to claim 5, characterized in that: After the mathematical simulation model in S3 is verified, it is necessary to analyze the flow rate under different working conditions, the maximum flow rate inside the valve core assembly, the maximum flow rate position, etc., and then adjust the valve core displacement and the flow position structure accordingly according to the pressure-flow characteristics to reduce the pressure loss of the working medium when the valve core assembly moves, so as to ensure the smooth and rapid operation of the hydraulic support.

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