Method and device for controlling valve through automatic hydraulic system

Abstract

The invention relates to the technical field of valve control, in particular to a method and device for controlling a valve through an automatic hydraulic system. The hydraulic cylinder is mounted on one side of the valve and used for controlling the valve; the valve plate is installed at the output end of the hydraulic cylinder and used for making contact with and controlling opening and closing of the valve. The PLC control system is installed on the valve and used for automatically controlling the hydraulic cylinder through a sensor. The valve has the beneficial effects that the closing performance is good, leakage is not prone to occurring, the automation degree is high, the control precision of the valve is improved, the control function is complete, the opening degree of the valve can be accurately controlled, the operation impact is small, the valve plate is slowly opened and stopped, the rest is high in speed, equipment impact is reduced, the service life of equipment is prolonged, and waste is small; leakage pollution and waste are reduced through automatic detection.

Description

Technical Field

[0001] The invention relates to the technical field of valve control, in particular to a method and a device for controlling a valve by using an automatic hydraulic system. Background Art

[0002] Large valves are widely used in the industrial field, mainly for closing, opening and flow regulation of gases and liquids. Pneumatic control valves and electric control valves are more commonly used in the market. Pneumatic valves have a fast response speed, but low control accuracy. Electric valve actuators have a high failure rate, high requirements for the installation environment, low control accuracy, and are prone to jamming. Among large valves, pneumatic control valves and electric control valves have low control accuracy and high requirements for the installation environment. Hydraulically controlled valves are all conventional closing control valves. Conventional pneumatic valves use pneumatic reversing valves to drive actuators for control, and electric valves use motors to drive actuators for control.

[0003] Conventional hydraulically controlled large valves on the market are controlled by electromagnetic reversing valves, which control the hydraulic cylinder to control the opening and closing of the valves, and the throttle valve manually controls the opening and closing speed. Its disadvantages include poor valve closing, easy leakage, low degree of automation, insufficient valve control accuracy, single function, only able to close or open, inability to adjust flow, large operating impact, easy impact during valve closing and opening, short service life, high energy consumption, large equipment leakage, large pollution and waste, poor safety, large equipment impact, poor equipment safety, high workload and poor personnel safety, no speed control and position detection, inability to stop accurately, and no emergency safety operation function. Summary of the invention

[0004] The object of the present invention is to provide a method and device for controlling a valve using an automatic hydraulic system to solve the problems raised in the above background technology.

[0005] To achieve the above object, the present invention provides the following technical solution: a device for controlling a valve using an automatic hydraulic system, comprising:

[0006] valve;

[0007] A hydraulic cylinder, which is installed on one side of the valve and is used to control the valve;

[0008] A valve plate, which is installed at the output end of the hydraulic cylinder and is used to contact and control the opening and closing of the valve;

[0009] PLC control system,The PLC control system is installed on the valve and is used to automatically control the hydraulic cylinder through sensors.

[0010] Preferably, the hydraulic cylinder also includes a ball valve A, a proportional reversing valve, a balancing overflow valve, a check valve A, a ball valve B, an encoder, a check valve B, a ball valve C and a ball valve D. The ball valve A is connected after the pressure source of the hydraulic cylinder, the proportional reversing valve is connected to one side of the ball valve A, the balancing overflow valve is connected to the proportional reversing valve, the check valve A is connected to the return oil path of the proportional reversing valve, the ball valve B is connected between the proportional reversing valve and the balancing overflow valve, the ball valve C is installed on the rod chamber of the hydraulic cylinder, and the ball valve D is installed on the rodless chamber of the hydraulic cylinder.

[0011] Preferably, an accumulator is also installed inside the hydraulic cylinder, and the accumulator is connected to the hydraulic cylinder via a one-way valve B.

[0012] Preferably, a displacement sensor is also installed inside the hydraulic cylinder. The displacement sensor is installed between the valve plate and the hydraulic cylinder and is used to detect the displacement of the valve plate and the hydraulic cylinder.

[0013] Preferably, pressure sensor A, pressure sensor B and pressure sensor C are also installed inside the hydraulic cylinder. The pressure sensor A and pressure sensor B are respectively installed on the pipelines on both sides of the rodless chamber of the hydraulic cylinder, and the pressure sensor C is installed in the hydraulic cylinder on one side of the accumulator.

[0014] Based on the above device, the present invention also proposes a method for controlling a valve using an automatic hydraulic system, comprising the following steps:

[0015] S1. When the valve is opened, the PLC control system gives a signal to the Xa solenoid of the proportional reversing valve, the valve core of the proportional reversing valve moves and changes direction, one side of the working position starts to work, and the high-pressure oil passes through the pressure source through the ball valve A, the proportional reversing valve, and the balanced relief valve ball valve B into the rod chamber of the hydraulic cylinder, pushing the hydraulic cylinder to retract the piston rod, driving the valve plate to open the valve, allowing the medium to pass, and the return oil flows back through the balanced relief valve, the proportional reversing valve, and the check valve A to the T port. The hydraulic oil flows into the rod chamber of the hydraulic cylinder from one side of the balanced relief valve, and the control oil is separated to open the relief valve on the other side of the balanced relief valve to ensure that the return oil of the rodless chamber is unobstructed;

[0016] S2. When the valve is closed, the PLC control system sends the Xb signal to the proportional reversing valve, the valve core of the proportional reversing valve moves and changes direction, and the working position on the other side starts to work. The high-pressure oil passes through the pressure source through the ball valve A, the proportional reversing valve, and the balanced relief valve into the rodless chamber of the hydraulic cylinder, pushing the piston rod of the hydraulic cylinder to extend. The hydraulic cylinder drives the valve plate to close the valve and cut off the flow of the medium. The return oil flows back through the balanced relief valve, the proportional reversing valve, and the check valve A. The hydraulic oil flows into the rodless chamber of the hydraulic cylinder from the other side of the balanced relief valve, and the control oil is separated to open the relief valve on one side of the balanced relief valve to ensure that the return oil of the rodless chamber is unobstructed;

[0017] S3. After the valve is fully closed, the PLC control system sends a signal to cut off the power to the proportional reversing valve. The AB port of the proportional reversing valve is connected to the oil return port T and loses pressure. After the AB port of the proportional reversing valve loses pressure, the balance relief valve cuts off the return oil of the two chambers of the hydraulic cylinder. The high-pressure oil is sealed in the two chambers of the hydraulic cylinder. Under the action of the pressure oil, the valve plate is compressed and the valve is closed. The control system is not affected by external loads and pressures and is in a self-locking state. When the pressure sensor A detects that the pressure of the rodless chamber of the hydraulic cylinder is lower than the set value required for compression, the Xb of the proportional reversing valve is energized to supplement the pressure of the rodless chamber of the hydraulic cylinder through the pressure source to avoid leakage caused by loosening of the valve plate when it is compressed;

[0018] S4. High-pressure oil replenishes the accumulator with pressure oil through the one-way valve B. The high-pressure oil is stored in the accumulator. If the equipment fails or the power is off, the ball valve C is opened and the high-pressure oil enters the rod chamber of the hydraulic cylinder. The pressure oil pushes the piston back and opens the valve. The ball valve D is opened and the high-pressure oil enters the rodless chamber of the hydraulic cylinder, pushing the piston rod to extend and close the valve. The accumulator pressure is greater than the set pressure of the balance relief valve. The return oil flows back from the return oil port T through the balance relief valve and the proportional reversing valve. Ball valves C and D are normally closed ball valves.

[0019] S5. Displacement sensor and encoder are used to detect the position of valve. The two detections serve as backup and correction for each other. Their signals are input into PLC control system, and automatic control program is executed according to the position signal. When the valve plate starts to open, PLC control system controls the hydraulic oil flow of proportional reversing valve to reduce the movement speed of valve plate and the damage of valve plate seal caused by impact wear. When the valve plate opens to the position and stops, it reduces the speed of valve plate to reduce impact damage. PLC control system divides the speed of valve plate into multiple gears to improve the accuracy and efficiency of stop position and opening adjustment.

[0020] Compared with the prior art, the beneficial effects of the present invention are: the present invention has good closing performance, is not prone to leakage, has a high degree of automation, improves the control accuracy of the valve, has complete control functions, can accurately control the opening size of the valve, has small operating impact, the valve plate opens and stops slowly, and the rest is high speed, which reduces equipment impact, increases the service life of the equipment, reduces waste, automatically detects and reduces leakage pollution and waste, improves safety, has high equipment control accuracy and improves safety, reduces misoperation, improves personnel safety, adopts continuous speed automatic control, adopts dual position detection to improve control accuracy, has emergency safety operation function, and can be manually operated in the event of power failure and pressure loss. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1 It is the overall structure diagram of the present invention.

[0022] In the figure:

[0023] 1. Ball valve A; 2. Proportional reversing valve; 3. Balanced relief valve; 4. Pressure sensor A; 5. Check valve A; 6. Pressure sensor B; 7. Ball valve B; 8. PLC control system; 9. Valve; 10. Valve plate; 11. Encoder; 12. Hydraulic cylinder; 13. Displacement sensor; 14. Check valve B; 15. Accumulator; 16. Pressure sensor C; 17. Ball valve C; 18. Ball valve D. DETAILED DESCRIPTION

[0024] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0025] Example

[0026] See also Figure 1 The present invention provides a technical solution: a device for controlling a valve using an automatic hydraulic system, comprising:

[0027] Valve 9;

[0028] A hydraulic cylinder 12, which is installed on one side of the valve 9 and is used to control the valve 9;

[0029] A valve plate 10, which is installed at the output end of the hydraulic cylinder 12 and is used to contact and control the opening and closing of the valve 9;

[0030] PLC control system 8, which is installed on valve 9 and is used to automatically control hydraulic cylinder 12 through sensors.

[0031] In this embodiment, it should also be noted that the hydraulic cylinder 12 also includes a ball valve A1, a proportional reversing valve 2, a balancing overflow valve 3, a one-way valve A5, a ball valve B7, an encoder 11, a one-way valve B14, a ball valve C17 and a ball valve D18. The ball valve A1 is connected after the pressure source of the hydraulic cylinder 12, the proportional reversing valve 2 is connected to one side of the ball valve A1, the balancing overflow valve 3 is connected to the proportional reversing valve 2, the one-way valve A5 is connected to the return oil path of the proportional reversing valve 2, the ball valve B7 is connected between the proportional reversing valve 2 and the balancing overflow valve 3, the ball valve C17 is installed on the rod chamber of the hydraulic cylinder 12, and the ball valve D18 is installed on the rodless chamber of the hydraulic cylinder 12.

[0032] In this embodiment, it should also be noted that an accumulator 15 is also installed inside the hydraulic cylinder 12, and the accumulator 15 is connected to the hydraulic cylinder 12 via a one-way valve B14.

[0033] In this embodiment, it should also be noted that a displacement sensor 13 is also installed inside the hydraulic cylinder 12 . The displacement sensor 13 is installed between the valve plate 10 and the hydraulic cylinder 12 to detect the displacement of the valve plate 10 and the hydraulic cylinder 12 .

[0034] In this embodiment, a pressure sensor A4, a pressure sensor B6 and a pressure sensor C16 are also installed inside the hydraulic cylinder 12. The pressure sensor A4 and the pressure sensor B6 are respectively installed on the pipelines on both sides of the rodless chamber of the hydraulic cylinder 12, and the pressure sensor C16 is installed in the hydraulic cylinder 12 on one side of the accumulator 15.

[0035] Specifically, when the present invention is used, when the valve 9 is opened, the PLC control system 8 gives the Xa solenoid signal to the proportional reversing valve 2, the valve core of the proportional reversing valve 2 moves and changes direction, and one side of the working position starts to work. The high-pressure oil passes through the pressure source through the ball valve A1, the proportional reversing valve 2, and the ball valve B7 of the balancing relief valve 3 and enters the rod chamber of the hydraulic cylinder 12, pushing the hydraulic cylinder 12 to retract the piston rod, driving the valve plate 10 to open the valve 9, allowing the medium to pass, and the return oil flows back to the T port through the balancing relief valve 3, the proportional reversing valve 2, and the one-way valve A5. The hydraulic oil flows into the rod chamber of the hydraulic cylinder from one side of the balancing relief valve 3, and the control oil is separated to open the relief valve on the other side of the balancing relief valve 3, so as to ensure that the return oil of the rodless chamber is unobstructed;

[0036] When valve 9 is closed, PLC control system 8 gives Xb signal to proportional reversing valve 2, the valve core of proportional reversing valve 2 moves and changes direction, the working position on the other side starts to work, and high-pressure oil passes through ball valve A1, proportional reversing valve 2 and balanced relief valve 3 through pressure source into the rodless chamber of hydraulic cylinder 12, pushing the piston rod of hydraulic cylinder 12 to extend, hydraulic cylinder 12 drives valve plate 10 to close valve 9, cuts off the flow of medium, and the return oil flows back through balanced relief valve 3, proportional reversing valve 2 and check valve A5. The hydraulic oil flows into the rodless chamber of hydraulic cylinder from the other side of balanced relief valve 3, and at the same time separates the control oil to open the relief valve on one side of balanced relief valve 3, so as to ensure the smooth return oil of rodless chamber.

[0037] After the valve 9 is closed, the PLC control system 8 sends a signal to cut off the power to the proportional reversing valve 2. The AB port of the proportional reversing valve 2 is connected to the oil return port T and loses pressure. After the AB port of the proportional reversing valve 2 loses pressure, the balancing relief valve 3 cuts off the return oil of the two chambers of the hydraulic cylinder 12. The high-pressure oil is sealed in the two chambers of the hydraulic cylinder 12. Under the action of the pressure oil, the valve plate 10 is compressed and the valve 9 is closed. The control system is not affected by external loads and pressures and is in a self-locking state. When the pressure sensor A4 detects that the pressure of the rodless chamber of the hydraulic cylinder 12 is lower than the set value required for compression, the Xb of the proportional reversing valve 2 is energized to supplement the pressure of the rodless chamber of the hydraulic cylinder 12 through the pressure source to avoid the valve plate 10 from loosening when compressed and causing leakage;

[0038] The high-pressure oil replenishes the accumulator 15 through the one-way valve B14. The high-pressure oil is stored in the accumulator 15. If the equipment fails or the power is off, the ball valve C17 is opened and the high-pressure oil enters the rod chamber of the hydraulic cylinder 12. The pressure oil pushes the piston back and opens the valve 9. The ball valve D18 is opened and the high-pressure oil enters the rodless chamber of the hydraulic cylinder 12, pushing the piston rod to extend and close the valve 9. The pressure of the accumulator 15 is greater than the set pressure of the balance relief valve 3. The return oil flows back from the return oil port T through the balance relief valve 3 and the proportional reversing valve 2. The ball valves C17 and D18 are normally closed ball valves.

[0039] The displacement sensor 13 and the encoder 11 are used to detect the position of the valve. The two detections are backup and calibrated with each other. Their signals are input into the PLC control system 8, which executes the automatic control program according to the position signal. When the valve plate 10 starts to open, the PLC control system 8 controls the hydraulic oil flow of the proportional reversing valve 2 to reduce the movement speed of the valve plate 10 and reduce the damage to the valve plate seal caused by impact wear. When the valve plate 10 opens to the position and stops, the speed of the valve plate 10 is reduced to reduce impact damage. The PLC control system 8 divides the speed of the valve plate 10 into multiple gears to improve the accuracy and efficiency of the stop position and opening adjustment.

[0040] In summary, the present invention has good closing performance and is not prone to leakage. The high-pressure oil sealing design of the two chambers of the hydraulic cylinder and the real-time monitoring of the pressure sensor ensure that the valve plate fits tightly in the closed state to effectively prevent leakage. Secondly, the degree of automation is high, and the control accuracy of the valve is significantly improved. The PLC control system automatically adjusts the action of the hydraulic cylinder according to the sensor signal to achieve precise control of the valve. In addition, the present invention has comprehensive control functions, can accurately control the opening size of the valve, and has small operating impact. The valve plate adopts a slow opening and slow stopping design, and runs at high speed the rest of the time, which effectively reduces equipment impact and extends equipment service life. At the same time, the automatic detection function reduces leakage pollution and waste, improves safety, and also adopts continuous speed automatic control. Dual-position detection improves control accuracy, and has emergency safety operation function, which can be manually operated in the event of power failure and pressure loss.

[0041] In the description of the present invention, it is necessary to understand that the terms "coaxial", "bottom", "one end", "top", "middle", "the other end", "upper", "one side", "top", "inside", "front", "center", "both ends" and the like indicate orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as a limitation on the present invention.

[0042] In addition, the terms "first", "second", "third" and "fourth" are used for descriptive purposes only and are not to be understood as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Thus, the features defined as "first", "second", "third" and "fourth" may explicitly or implicitly include at least one of such features.

[0043] In the present invention, unless otherwise clearly stipulated and limited, the terms such as "installation", "setting", "connection", "fixation" and "screw-on" should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integral one; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium; it can be the internal connection of two elements or the interaction relationship between two elements. Unless otherwise clearly defined, ordinary technicians in this field can understand the specific meanings of the above terms in the present invention according to the specific circumstances.

[0044] Although embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present invention, and that the scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. A device for controlling a valve using an automatic hydraulic system, characterized in that: include: Valve (9); A hydraulic cylinder (12), the hydraulic cylinder (12) being installed on one side of the valve (9) and used for controlling the valve (9); A valve plate (10), the valve plate (10) being mounted at the output end of the hydraulic cylinder (12) and being used for contacting and controlling the opening and closing of the valve (9); A PLC control system (8) is installed on the valve (9) and is used to automatically control the hydraulic cylinder (12) through a sensor.

2. A device for controlling a valve using an automatic hydraulic system according to claim 1, characterized in that: The hydraulic cylinder (12) further comprises a ball valve A (1), a proportional reversing valve (2), a balancing overflow valve (3), a check valve A (5), a ball valve B (7), an encoder (11), a check valve B (14), a ball valve C (17) and a ball valve D (18), wherein the ball valve A (1) is connected after the pressure source of the hydraulic cylinder (12), the proportional reversing valve (2) is connected to one side of the ball valve A (1), the balancing overflow valve (3) is connected to the proportional reversing valve (2), the check valve A (5) is connected to the oil return path of the proportional reversing valve (2), the ball valve B (7) is connected between the proportional reversing valve (2) and the balancing overflow valve (3), the ball valve C (17) is installed on the rod chamber of the hydraulic cylinder (12), and the ball valve D (18) is installed on the rodless chamber of the hydraulic cylinder (12).

3. The device for controlling a valve using an automatic hydraulic system according to claim 1, characterized in that: An accumulator (15) is also installed inside the hydraulic cylinder (12), and the accumulator (15) is connected to the hydraulic cylinder (12) via a one-way valve B (14).

4. The device for controlling a valve using an automatic hydraulic system according to claim 1, characterized in that: A displacement sensor (13) is also installed inside the hydraulic cylinder (12); the displacement sensor (13) is installed between the valve plate (10) and the hydraulic cylinder (12) and is used to detect the displacement of the valve plate (10) and the hydraulic cylinder (12).

5. The device for controlling a valve using an automatic hydraulic system according to claim 1, characterized in that: A pressure sensor A (4), a pressure sensor B (6) and a pressure sensor C (16) are also installed inside the hydraulic cylinder (12). The pressure sensor A (4) and the pressure sensor B (6) are respectively installed on the pipelines on both sides of the rodless chamber of the hydraulic cylinder (12), and the pressure sensor C (16) is installed in the hydraulic cylinder (12) on one side of the accumulator (15).

6. A method for controlling a valve using an automatic hydraulic system, according to any one of claims 1 to 5, wherein the device for controlling a valve using an automatic hydraulic system is characterized in that: The following steps are involved: S1. When the valve (9) is opened, the PLC control system (8) sends a signal to the Xa solenoid of the proportional reversing valve (2), and the valve core of the proportional reversing valve (2) moves and changes direction. One side of the working position starts to work, and the high-pressure oil passes through the pressure source through the ball valve A (1), the proportional reversing valve (2), the balance relief valve (3) and the ball valve B (7) into the rod chamber of the hydraulic cylinder (12), pushing the hydraulic cylinder (12) to retract the piston rod, driving the valve plate (10) to open the valve (9), allowing the medium to pass through, and the return oil flows back to the port through the balance relief valve (3), the proportional reversing valve (2) and the check valve A (5). The hydraulic oil flows into the rod chamber of the hydraulic cylinder from one side of the balance relief valve (3), and the control oil is separated to open the relief valve on the other side of the balance relief valve (3), ensuring that the return oil of the rodless chamber is unobstructed; S2. When the valve (9) is closed, the PLC control system (8) sends the Xb signal to the proportional reversing valve (2), the valve core of the proportional reversing valve (2) moves and changes direction, and the working position on the other side starts to work. The high-pressure oil passes through the pressure source through the ball valve A (1), the proportional reversing valve (2), and the balanced relief valve (3) into the rodless chamber of the hydraulic cylinder (12), pushing the piston rod of the hydraulic cylinder (12) to extend. The hydraulic cylinder (12) drives the valve plate (10) to close the valve (9), cutting off the flow of the medium. The return oil flows back through the balanced relief valve (3), the proportional reversing valve (2), and the check valve A (5). The hydraulic oil flows into the rodless chamber of the hydraulic cylinder from the other side of the balanced relief valve (3), and the control oil is separated to open the relief valve on one side of the balanced relief valve (3), ensuring that the return oil of the rodless chamber is unobstructed; S3. After the valve (9) is fully closed, the PLC control system (8) sends a signal to the proportional reversing valve (2) to cut off the power supply. The AB port of the proportional reversing valve (2) is connected to the oil return port and loses pressure. After the AB port of the proportional reversing valve (2) loses pressure, the balancing relief valve (3) cuts off the oil return from the two chambers of the hydraulic cylinder (12). The high-pressure oil is sealed in the two chambers of the hydraulic cylinder (12). Under the action of the pressure oil, the valve plate (10) is compressed and the valve (9) is closed. The control system is not affected by external loads and pressures and is in a self-locking state. When the pressure sensor A (4) detects that the pressure of the rodless chamber of the hydraulic cylinder (12) is lower than the set value required for compression, the Xb of the proportional reversing valve (2) is energized to supplement the pressure of the rodless chamber of the hydraulic cylinder (12) through the pressure source to prevent the valve plate (10) from loosening when compressed and causing leakage; S4. The high-pressure oil is supplied to the accumulator (15) through the one-way valve B (14). The high-pressure oil is stored in the accumulator (15). If the equipment fails or the power is off, the ball valve C (17) is opened and the high-pressure oil enters the rod chamber of the hydraulic cylinder (12). The pressure oil pushes the piston back and opens the valve (9). The ball valve D (18) is opened and the high-pressure oil enters the rodless chamber of the hydraulic cylinder (12), pushing the piston rod to extend and close the valve (9). The pressure of the accumulator (15) is greater than the set pressure of the balance relief valve (3). The return oil flows back from the return oil port through the balance relief valve (3) and the proportional reversing valve (2). The ball valves C (17) and D (18) are normally closed ball valves. S5. The displacement sensor (13) and the encoder (11) are used to detect the position of the valve. The two detections are mutually backup and calibrated. Their signals are input into the PLC control system (8). (8) executes the automatic control program according to the position signal. When the valve plate (10) starts to open, the PLC control system (8) controls the hydraulic oil flow of the proportional reversing valve (2) to reduce the movement speed of the valve plate (10) and reduce the damage to the valve plate seal caused by impact wear. When the valve plate (10) opens to the stop position, the speed of the valve plate (10) is reduced to reduce impact damage. The PLC control system (8) divides the speed of the valve plate (10) into multiple gears to improve the accuracy and efficiency of the stop position and opening adjustment.

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