CN113389932A - Electro-hydraulic valve differential hydraulic system - Google Patents

Electro-hydraulic valve differential hydraulic system Download PDF

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Publication number
CN113389932A
CN113389932A CN202010184319.XA CN202010184319A CN113389932A CN 113389932 A CN113389932 A CN 113389932A CN 202010184319 A CN202010184319 A CN 202010184319A CN 113389932 A CN113389932 A CN 113389932A
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CN
China
Prior art keywords
valve
hydraulic
check valve
pilot
output end
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Pending
Application number
CN202010184319.XA
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Chinese (zh)
Inventor
王庆宪
王俊凤
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Baoding Xinhua Petrochemical Equipment Manufacturing Co ltd
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Baoding Xinhua Petrochemical Equipment Manufacturing Co ltd
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Baoding Xinhua Petrochemical Equipment Manufacturing Co ltd filed Critical Baoding Xinhua Petrochemical Equipment Manufacturing Co ltd
Priority to CN202010184319.XA priority Critical patent/CN113389932A/en
Publication of CN113389932A publication Critical patent/CN113389932A/en
Pending legal-status Critical Current

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    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F16—ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
    • F16K—VALVES; TAPS; COCKS; ACTUATING-FLOATS; DEVICES FOR VENTING OR AERATING
    • F16K31/00—Actuating devices; Operating means; Releasing devices
    • F16K31/12—Actuating devices; Operating means; Releasing devices actuated by fluid
    • F16K31/122—Actuating devices; Operating means; Releasing devices actuated by fluid the fluid acting on a piston
    • F16K31/124—Actuating devices; Operating means; Releasing devices actuated by fluid the fluid acting on a piston servo actuated
    • F16K31/1245—Actuating devices; Operating means; Releasing devices actuated by fluid the fluid acting on a piston servo actuated with more than one valve
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F15—FLUID-PRESSURE ACTUATORS; HYDRAULICS OR PNEUMATICS IN GENERAL
    • F15B—SYSTEMS ACTING BY MEANS OF FLUIDS IN GENERAL; FLUID-PRESSURE ACTUATORS, e.g. SERVOMOTORS; DETAILS OF FLUID-PRESSURE SYSTEMS, NOT OTHERWISE PROVIDED FOR
    • F15B1/00—Installations or systems with accumulators; Supply reservoir or sump assemblies
    • F15B1/02—Installations or systems with accumulators
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F15—FLUID-PRESSURE ACTUATORS; HYDRAULICS OR PNEUMATICS IN GENERAL
    • F15B—SYSTEMS ACTING BY MEANS OF FLUIDS IN GENERAL; FLUID-PRESSURE ACTUATORS, e.g. SERVOMOTORS; DETAILS OF FLUID-PRESSURE SYSTEMS, NOT OTHERWISE PROVIDED FOR
    • F15B11/00—Servomotor systems without provision for follow-up action; Circuits therefor
    • F15B11/02—Systems essentially incorporating special features for controlling the speed or actuating force of an output member
    • F15B11/024—Systems essentially incorporating special features for controlling the speed or actuating force of an output member by means of differential connection of the servomotor lines, e.g. regenerative circuits
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F15—FLUID-PRESSURE ACTUATORS; HYDRAULICS OR PNEUMATICS IN GENERAL
    • F15B—SYSTEMS ACTING BY MEANS OF FLUIDS IN GENERAL; FLUID-PRESSURE ACTUATORS, e.g. SERVOMOTORS; DETAILS OF FLUID-PRESSURE SYSTEMS, NOT OTHERWISE PROVIDED FOR
    • F15B11/00—Servomotor systems without provision for follow-up action; Circuits therefor
    • F15B11/08—Servomotor systems without provision for follow-up action; Circuits therefor with only one servomotor
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F15—FLUID-PRESSURE ACTUATORS; HYDRAULICS OR PNEUMATICS IN GENERAL
    • F15B—SYSTEMS ACTING BY MEANS OF FLUIDS IN GENERAL; FLUID-PRESSURE ACTUATORS, e.g. SERVOMOTORS; DETAILS OF FLUID-PRESSURE SYSTEMS, NOT OTHERWISE PROVIDED FOR
    • F15B13/00—Details of servomotor systems ; Valves for servomotor systems
    • F15B13/02—Fluid distribution or supply devices characterised by their adaptation to the control of servomotors
    • F15B13/04—Fluid distribution or supply devices characterised by their adaptation to the control of servomotors for use with a single servomotor

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  • Engineering & Computer Science (AREA)
  • General Engineering & Computer Science (AREA)
  • Mechanical Engineering (AREA)
  • Physics & Mathematics (AREA)
  • Fluid Mechanics (AREA)
  • Fluid-Pressure Circuits (AREA)

Abstract

The invention relates to a differential hydraulic system for an electro-hydraulic valve driving device. The hydraulic system uses an energy accumulator to store energy, 4 hydraulic control one-way valves, one-way valve and 2 electromagnetic valves to control the hydraulic cylinder, so that the hydraulic cylinder drives the valve to open and close in a differential mode. When the power is off, the normally open electromagnetic valve is opened, and the valve is automatically closed by utilizing the energy of the energy accumulator.

Description

Electro-hydraulic valve differential hydraulic system
Technical Field
The present invention relates to a hydraulic system, in particular a differential hydraulic system for emergency shut-off valve drive for a hazardous liquid storage tank.
Background
At present, the electrohydraulic valve emergency shut-off device used in China is mainly a foreign product, the device is an electrohydraulic system, and a computer is used for operating 3 electromagnetic valves to control a hydraulic cylinder and drive a valve rod of a valve to realize the opening and closing functions of the valve. The hydraulic system stores energy by using an energy accumulator, and the energy stored by the energy accumulator is used for pushing the hydraulic cylinder to close the valve under the condition of power supply interruption. At present, the domestic electro-hydraulic system using 2 solenoid valves and 2 pilot-controlled valves operates the valves, but the 2 hydraulic systems have the same defect that the closing force of the valve is larger than the opening force under the constant oil pressure. Valve actuators typically require an opening force that is greater than a closing force to prevent the valve from opening after it is closed. Thus, existing electrohydraulic valve assemblies are not suitable for the operational requirements of operating the valve.
Disclosure of Invention
The differential hydraulic system used by the invention is characterized in that 2 plug-in solenoid valves, 4 plug-in hydraulic control one-way valves and plug-in one-way valves are arranged on one oil circuit block to form a basic oil circuit system, and the outside of the oil circuit block and other hydraulic components such as a hydraulic pump, an energy accumulator and the like are combined into a differential emergency shutoff valve hydraulic system. The opening force of the differential working hydraulic cylinder under constant oil pressure is larger than the closing force, and the working requirement of valve operation is met.
The technical scheme adopted by the invention is as follows: the basic hydraulic control system is formed by using plug-in components on an oil circuit block. The plug-in components comprise 4 hydraulic control one-way valves, one-way valve, 2 electromagnetic valves and an overflow valve. In addition, 2 cylindrical throttle valves are also arranged in the oil circuit block. The oil path block and peripheral hydraulic components such as a hydraulic pump and the like form a differential hydraulic system. 2 electromagnetic valves, one is a normally closed electromagnetic valve, and the other is a normally open electromagnetic valve; 4 pilot operated check valves, 2 are that the check valve can open in reverse direction after the control end loading, and 2 are that the check valve two-way closed after the control end loading. The output end of the normally open electromagnetic valve (22) is connected to the input end of the hydraulic control one-way valve (13) and the control end of the hydraulic control one-way valve (20), and the output end of the hydraulic control one-way valve (13) is connected to the rear cavity oil port of the hydraulic cylinder and the output ends of the hydraulic control one-way valve (16) and the hydraulic control one-way valve (19). The control ends of the hydraulic control one-way valve (13), the hydraulic control one-way valve (16) and the hydraulic control one-way valve (20) are connected to the output end of the normally closed electromagnetic valve (21). The output end of the normally closed electromagnetic valve (21) is also connected to the input end of the check valve (18), and the output end of the check valve (18) is connected to the front cavity oil port of the hydraulic cylinder 17 and the input end of the hydraulic control check valve (16). When the valve is closed, the electromagnetic valve (22) is always opened to be conducted, high-pressure oil passes through the hydraulic control one-way valve (13) to the oil port of the rear cavity of the hydraulic cylinder (17), and the oil in the front cavity of the hydraulic cylinder (17) also enters the rear cavity of the hydraulic cylinder (17) through the hydraulic control one-way valve (16) when the piston is pushed to advance. When the normally closed electromagnetic valve (21) is conducted, high-pressure oil enters the control ends of the hydraulic control one-way valve (13), the hydraulic control one-way valve (16) and the hydraulic control one-way valve (19), meanwhile, the high-pressure oil enters the front cavity of the hydraulic cylinder (17) through the one-way valve (18), and because the hydraulic control one-way valve (19) is reversely opened under the control of the high-pressure oil, the oil in the rear cavity of the hydraulic cylinder (17) returns to the oil tank (1) through the hydraulic control one-way valve (19). The hydraulic system is locked in two directions, and the hydraulic cylinder (17) maintains pressure. A hydraulic control one-way valve (13) and a hydraulic control one-way valve (20) in the system are used for preventing the hydraulic control one-way valve (19) from being locked by high-pressure oil, and after a normally closed electromagnetic valve (21) is opened, the high-pressure oil directly flows back to an oil tank (1) through the hydraulic control one-way valve (19) to enable the system to be incapable of working normally. The hydraulic control check valve (13) and the hydraulic control check valve (20) are arranged, when the normally open electromagnetic valve (22) is conducted, the hydraulic control check valve (13) is locked, high-pressure oil cannot flow through the hydraulic control check valve (13), but the hydraulic control check valve (20) can be opened through the control end of the hydraulic control check valve (20), the hydraulic control check valve (19) can be closed after the pressure of the control end of the hydraulic control check valve (19) is reduced, the pressure of the control end of the hydraulic control check valve (13) can also be reduced, the hydraulic control check valve (13) is opened, the high-pressure oil enters the rear cavity of the hydraulic cylinder (17) through the hydraulic control check valve (13) and enters a normal working state. The system can also be used without the pilot-operated check valve (20), and an adjustable throttle valve (25) is arranged at the control end of the pilot-operated check valve (19), and a cylindrical throttle valve (24) is arranged between the output end of the normally closed electromagnetic valve (21) and the control end of the pilot-operated check valve (19). When the normally closed electromagnetic valve (21) is conducted, the high-pressure oil provides control pressure for the hydraulic control one-way valve (19) through the throttle valve (24), and when the normally closed electromagnetic valve is closed, the adjustable throttle valve (25) unloads the control end of the hydraulic control one-way valve (19), and closes the hydraulic control one-way valve (19). The solution has the advantage of simpler structure and the disadvantage that when the normally closed solenoid valve (21) is switched on, a part of high pressure oil leaks through the adjustable throttle valve, but the leakage amount is negligible because of low leakage. In the production process, the emergency state is firstly power off, a normally open electromagnetic valve is used as a hydraulic system of a valve driving device of the safety device, the normally open electromagnetic valve (22) is opened when the power is off, and high-pressure oil in the energy accumulator (10) drives a hydraulic cylinder (17) to close the valve. The hydraulic system is also equipped with a manual pump (4) and a manual switch (8) for manually operating the valve to open or close in the event of a power failure.
The invention has the beneficial effects that: the differential hydraulic system is more in line with the working requirements of operating valves.
Drawings
FIG. 1 is a schematic diagram of a hydraulic system of the present invention.
FIG. 2 is a schematic diagram of a modified hydraulic system of the present invention.
In fig. 1, an oil tank, 2, a filter screen oil filling port, 3, an oil filter, 4, a manual oil pump, 5, an electric hydraulic pump, 6, a check valve, 7, a check valve, 8, a manual valve, 9, a check valve, 10, an accumulator, 11, a pressure gauge, 12, a pressure sensor, 13, a hydraulic control check valve, 14, a throttle valve, 15, a throttle valve, 16, a hydraulic control check valve, 17, a hydraulic cylinder, 18, a check valve, 19, a hydraulic control check valve, 20, a hydraulic control check valve, 21, a normally closed electromagnetic valve, 22, a normally open electromagnetic valve, 23 and an overflow valve.
In fig. 2, 24, a throttle, 25, an adjustable throttle.
Detailed Description
The invention is further illustrated with reference to the following figures and examples.
In fig. 1 a hydraulic system working principle diagram is shown. In fig. 1, the front end of the electric hydraulic pump 5 is a high-pressure oil path, the rear end of the electric hydraulic pump is an oil supply path, the oil supply path is composed of an oil filter 3, an electric hydraulic pump 5, a manual pump 4 and a pipeline, and the electric hydraulic pump 5 pumps hydraulic oil from an oil tank 1 and supplies the hydraulic oil to the high-pressure oil path after being pressurized. The high-pressure oil circuit consists of check valves 6, 7 and 9, an energy accumulator 10, a pressure gauge 11, a pressure sensor 12, a manual valve 8, a normally open electromagnetic valve 22, an overflow valve 23, a normally closed electromagnetic valve 21 and pipelines. The pressure gauge 11 displays the pipeline pressure, the pressure sensor 12 transmits the pipeline pressure data to the computer, and when the pipeline pressure is lower than the set minimum pressure value, the computer starts the electric hydraulic pump 5, injects and pressurizes oil into the pipeline, and simultaneously stores high-pressure oil into the energy accumulator 10. When the computer detects that the pipeline pressure exceeds the set high pressure value through the pressure sensor 12, the operation of the electric hydraulic pump 5 is stopped. The relief valve 23 is used for controlling the system pressure so that the pressure of the high-pressure oil path does not exceed the design pressure. The check valves 6, 7, and 9 function to ensure one-way flow of the pressure oil and prevent the high-pressure oil in the accumulator 10 from flowing back to the oil tank 1 when the electric hydraulic pump 5 stops operating. The function of the manual pump 4 is to supply high pressure oil to the hydraulic system in the event of a power failure. In a normal state, the switch position of the manual valve 8 is that the oil path from the high-pressure oil path to the normally open electromagnetic valve 22 is opened, the oil path from the high-pressure oil path to the normally closed electromagnetic valve 21 is closed, the normally closed electromagnetic valve 21 is powered off, and the normally open electromagnetic valve 22 is powered on. The normally open electromagnetic valve 22, the normally closed electromagnetic valve 21, the hydraulic control one-way valve 13, the hydraulic control one-way valve 16, the hydraulic control one-way valve 19, the hydraulic control one-way valve 20, the overflow valve 23 and the one-way valve 18 are all installed on an oil circuit block in a cartridge valve mode to form a basic hydraulic system, and the cylindrical throttle valve 14 and the throttle valve 15 are installed in oil holes in the oil circuit block. The output end of the normally open electromagnetic valve 22 is connected to the control end of the pilot-controlled check valve 20 and the input end of the pilot-controlled check valve 13, and the output end of the pilot-controlled check valve 13 is connected to the rear cavity oil port of the hydraulic cylinder 17, the output end of the pilot-controlled check valve 16 and the output end of the pilot-controlled check valve 19. The output of the normally closed solenoid valve 21 is connected to the input of the check valve 18 and the pilot of the pilot operated check valve 19, to the pilot of the pilot operated check valve 13 through the throttle valve 14, and to the output of the pilot operated check valve 20 through the throttle valve 15. The output end of the check valve 18 is connected to the input end of the pilot operated check valve 16 and the front port of the hydraulic cylinder 17. The input end of the manual valve 8 is connected to the high-pressure oil path, one output end is connected to the input end of the normally open electromagnetic valve 22, and the other output end is connected to the output end of the normally closed electromagnetic valve 21.
When the valve is closed, the normally open electromagnetic valve 22 is powered off and opened, high-pressure oil flows to the rear cavity oil port of the hydraulic cylinder 7 through the hydraulic control one-way valve 13, and when the piston moves forwards, the pressure of the front cavity hydraulic oil rises and enters the rear cavity of the hydraulic cylinder 17 through the hydraulic control one-way valve 16. The output end of the normally open electromagnetic valve 22 is also connected with the control end of the pilot-controlled check valve 20.
When the valve is opened, the normally closed electromagnetic valve 21 is electrified and opened, high-pressure oil is communicated to the control ends of the hydraulic control one- way valves 13, 16 and 19, the hydraulic control one-way valves 13 and 16 are closed in a two-way mode, the hydraulic control one-way valve 19 is opened in a reverse direction, the high-pressure oil enters the front cavity oil port of the hydraulic cylinder 17 after passing through the one-way valve 18, and when the piston retreats, the rear cavity hydraulic oil returns to the oil tank 1 through the hydraulic control one-way valve 19.
The hydraulic cylinder is locked in a two-way mode, after the valve is closed, the hydraulic control one-way valve 20 is locked in a reverse opening position, when the valve is switched to be opened, due to the flow limiting effect of the throttle valve 15, the hydraulic control one-way valve 19 is opened in the reverse direction by high-pressure oil at the output end of the normally closed electromagnetic valve 21, the hydraulic control one-way valve 16 is closed in the two-way mode, the pressure of the rear cavity of the oil cylinder 17 is reduced after the hydraulic control one-way valve 19 is opened in the reverse direction, control pressure oil locking the hydraulic control one-way valve 20 flows through the hydraulic control one-way valve 13 to be unloaded, and the hydraulic control one-way valve 20 is closed. The sectional area of the throttle valve 14 is smaller than that of the throttle valve 15, and the throttle valve is used for limiting the rising speed of the pressure at the control ends of the hydraulic control one-way valves 13 and 20, so that the hydraulic control one-way valve 19 is opened first and then the hydraulic control one-way valve 13 is closed. After the valve opening operation is completed, the pilot operated check valves 13, 16 are locked in the two-way closed state, and the pilot operated check valve 19 is locked in the reverse opening state. When the closing valve is operated, the high-pressure oil at the output end of the normally open solenoid valve 22 passes through the control end of the pilot-operated check valve 20 to reversely open the pilot-operated check valve 20, unload the control end of the pilot-operated check valves 13, 16 and 19, unlock the pilot-operated check valve 13, and then enter the working process of closing the valve operation as described above.
Figure 2 shows a schematic diagram of a modified hydraulic system of the present invention. In fig. 2, pilot operated check valve 20 and throttle valve 15 of the system of fig. 1 are removed and a throttle valve 24 and an adjustable throttle valve 25 are added. With the adjustable throttle 25, the pilot side of the pilot operated check valve 19 is easily unloaded. After the valve opening operation is finished and the normally closed electromagnetic valve 21 is closed, the control end of the pilot operated check valve 19 is unloaded through the throttle valve 25 and the pilot operated check valve 19 is closed. The function of the throttle valve 24 is to reduce the leakage of high-pressure oil through the adjustable throttle valve 25 when the valve is opened.

Claims (4)

1. An electro-hydraulic valve differential hydraulic system for valve operation, characterized by: the hydraulic system consists of an electric hydraulic pump 5, an energy accumulator 10, a hydraulic cylinder 17, a manual pump 4, a manual valve 8, a normally open electromagnetic valve 22, a normally closed electromagnetic valve 21, hydraulic control one-way valves 13 and 16 capable of being closed in two directions, hydraulic control one-way valves 19 and 20 capable of being opened in reverse directions, an overflow valve 23, throttle valves 14 and 15, a one-way valve 18, one-way valves 6, 7 and 9, an oil filter 3, an oil tank 1 and a pipeline; the output end of the normally open electromagnetic valve 22 is connected to the control end of the pilot-controlled check valve 20 and the input end of the pilot-controlled check valve 13, and the output end of the pilot-controlled check valve 13 is connected to the rear cavity oil port of the hydraulic cylinder 17, the output end of the pilot-controlled check valve 16 and the output end of the pilot-controlled check valve 19; the output end of the normally closed electromagnetic valve 21 is connected to the input end of the check valve 18 and the control end of the pilot-controlled check valve 19, is connected to the control end of the pilot-controlled check valve 13 through the throttle valve 14, and is connected to the output end of the pilot-controlled check valve 20 through the throttle valve 15; the output end of the check valve 18 is connected to the input end of the hydraulic control check valve 16 and the front end oil port of the hydraulic cylinder 17; the input end of the hydraulic control one-way valve 19 is connected to the oil tank 1; the input end of the manual valve 8 is connected to a high-pressure oil circuit, one output end is connected to the input end of the normally open electromagnetic valve 22, and the other output end is connected to the output end of the normally closed electromagnetic valve; the system is modified to remove the pilot operated check valve 20 and the throttle valve 15 and add an adjustable throttle valve 25 and a throttle valve 24, and still achieve the same function.
2. The electro-hydraulic valve differential hydraulic system of claim 1, wherein: the normally open electromagnetic valve 22, the normally closed electromagnetic valve 21, the pilot operated check valve 13 capable of being closed bidirectionally, the pilot operated check valve 16 capable of being closed bidirectionally, the pilot operated check valve 19 capable of being opened reversely, the pilot operated check valve 20 capable of being opened reversely, the overflow valve 23, the check valve 18 which are inserted are arranged on the oil path block, and the cylindrical throttle valve 14 and the throttle valve 15 are arranged in an oil path in the oil path block to form a basic hydraulic system.
3. The electro-hydraulic valve differential hydraulic system of claim 1, wherein: the flow area of the throttle valve 14 is smaller than that of the throttle valve 15 so that the pilot operated check valve 20 opens before the pilot operated check valve 13 when the shut-off valve operates.
4. The electro-hydraulic valve differential hydraulic system of claim 1, wherein: in the basic hydraulic system, a pilot-controlled check valve 20 and a throttle valve 15 are removed, and an adjustable throttle valve 25 and a throttle valve 24 are added; the pilot operated check valve 19 has its control end connected to the output end of the normally closed solenoid valve 21 through a throttle valve, and the pilot operated check valve 19 has its control end connected to the oil tank 1 through an adjustable throttle valve 25.
CN202010184319.XA 2020-03-11 2020-03-11 Electro-hydraulic valve differential hydraulic system Pending CN113389932A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
CN202010184319.XA CN113389932A (en) 2020-03-11 2020-03-11 Electro-hydraulic valve differential hydraulic system

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
CN202010184319.XA CN113389932A (en) 2020-03-11 2020-03-11 Electro-hydraulic valve differential hydraulic system

Publications (1)

Publication Number Publication Date
CN113389932A true CN113389932A (en) 2021-09-14

Family

ID=77616286

Family Applications (1)

Application Number Title Priority Date Filing Date
CN202010184319.XA Pending CN113389932A (en) 2020-03-11 2020-03-11 Electro-hydraulic valve differential hydraulic system

Country Status (1)

Country Link
CN (1) CN113389932A (en)

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