A、 Application and performance specifications
- Application
This valve is a hydraulic control check butterfly valve, which is operated by hydraulic oil source. It is the latest generation of hydraulic control butterfly valve. It has the functions of both stop and check, and can replace two valves with one valve. It can close the valve in two stages, quick closing and slow closing, according to the preset procedure. It can significantly eliminate and inhibit the water hammer hazards caused by sudden power failure or accidental pump shutdown, and reverse rotation of the pump unit caused by media backflow. It is an effective equipment to ensure the safe and reliable operation of the pump unit and pipe network system.
B、 Structure, characteristics, parameters and working principle
- Structure
The valve is mainly composed of valve body, hydraulic device, hydraulic station and electric control box. See the attached figure for its external connection dimensions.
- Features
(1) This valve uses an accumulator to replace the heavy hammer in the heavy hammer type hydraulic control butterfly valve, which changes the potential energy of the heavy hammer into the fluid pressure energy required. It has the advantages of reasonable design, small volume, light weight, simple structure, complete functions, flexible and reliable action, beautiful appearance, energy saving and material saving, and convenient maintenance.
(2) The valve has a relatively complete hydraulic system and a reliable electrical control system, which can be operated locally or remotely, and is easy to operate.
The hydraulic station and electrical control box of the valve are installed separately from the valve body; The valve body can be arranged horizontally or installed vertically. It can be selected according to site conditions.
- Characteristic parameters of valve switch
The valve adopts a metal hard sealing structure. The oil cylinder drives the crank and the valve shaft drives the butterfly plate to rotate by 90 º to open and close the valve. The closing parameters of the valve can be adjusted by adjusting the adjusting plugs on the oil cylinder. The adjustment method is adjusted according to Table 1 below. The valve opening time, fast closing time and slow closing time have been set when leaving the factory. If required by the contract agreement when ordering, the user’s requirements shall prevail. If the ordering user has no requirements, the fast closing time is adjusted to 5 seconds, the slow closing time is adjusted to 15 seconds, and the fast and slow closing switching angle is adjusted to 90 ° – 25 ° fast closing and 25 ° – 0 ° slow closing. Set the valve opening time within 30~60 seconds. See Fig. (1) for the adjustment of fast and slow closing time and angle. The opening and closing time adjust the throttle valve 20 on the hydraulic station.
- Hydraulic Working Principle
(1) Routine work
1) Start the oil pump: after the power is supplied, the starting motor drives the oil pump to run. The hydraulic oil flows through the oil pump 1 → check valve 26, filter screen 2 → check valve 3 → accumulator switch 5 → accumulator 6. On this line, the pressure of the system is controlled by the electric contact pressure 7. When the oil pressure of the accumulator reaches high pressure, the oil pump stops supplying oil. When the accumulator pressure is lower than the lower limit of the set pressure, the electric contact pressure gauge 7 sends a signal to connect the oil pump motor to make the oil pump work.
When the on/off valve command is not issued, solenoid valve 11 and solenoid valve 19 are not energized, and the valve is in the stop locking state. The hydraulic power oil of accumulator 6 passes through accumulator switch 5 → cartridge valve 9 → stop valve 17 → rod cavity of oil cylinder. Since solenoid valve 19 is in the non energized state, the hydraulic oil enters the cavity of cartridge valve 12, and cartridge valve 12 is closed. Therefore, the hydraulic oil in the rodless chamber of the oil cylinder cannot be discharged through 21, 22 → 18 → 12, the piston does not move, and the valve remains locked in place.
2) Valve opening: press the opening button, solenoid valve 11 is electrified (solenoid valve 19 is not electrified), hydraulic control oil flows through the chamber of solenoid valve 11 → cartridge valve 9, and the cartridge valve 9 is closed. At the same time, the solenoid valve 11 controls the hydraulic control check valves 10 and 13 of the oil jack. Thus, the hydraulic pressure flows from the accumulator 6 through the switch 5 → one-way throttle valve 10, throttle valve 20 → stop valve 18 → one-way throttle valve 22 → rod less chamber of the oil cylinder → pushing the piston and connecting rod to open the butterfly valve. The oil with rod chamber returns to the oil tank through the stop valve 17 → hydraulic control check valve 13.
3) Valve closing: press the closing button, solenoid valve 19 is energized, solenoid valve 11 is not energized, the control hydraulic oil of cartridge valve 9 returns to the oil tank through solenoid valve 11, and cartridge valve 9 is open. At the same time, solenoid valve 19 is energized, the control hydraulic oil of cartridge valve 12 returns to the oil tank through solenoid valve 19, and cartridge valve 12 is also open. Power oil enters the cartridge through accumulator 6 → accumulator switch 5 → the side of cartridge valve 9 and pushes open the piston of cartridge valve. Power oil flows from the bottom of cartridge valve through stop valve 17 into the rod cavity of oil cylinder, The power oil in the rodless chamber enters the side of the cartridge valve 12 through the one-way throttle valve 22 and the travel throttle valve 21 → the stop valve 18 → the cartridge valve 12 to jack up the piston of the cartridge valve 12, and the power oil is discharged back to the oil tank through the bottom of the cartridge valve. Adjusting the position of the stroke throttle valve 21 during the closing process can change the fast and slow switching angle of the valve by 25 ° ± 10 °, and the fast closing time is adjusted by the fast joint flow plug. The slow closing time is adjusted by the throttle plug 22.
4) Stop at any position: When the butterfly valve is opened or closed, press the stop button, and both solenoid valves are not energized. Although the hydraulic oil enters the rod cavity through the cartridge valve 9, since the cartridge valve 12 is closed, the oil in the rod cavity of the oil cylinder cannot be discharged, so the butterfly plate is locked at any position (this function cannot be used to regulate the flow).
(2) The electric oil pump directly provides pressure oil to open and close the butterfly valve: (cut off the pressure oil in the accumulator and close the manual stop valve. 5) Press the valve opening or closing button to start the motor. The pressure oil of the oil pump enters the rear or front of the oil cylinder to open and close the butterfly valve at a constant speed.
(3) Replenishing pressure oil of the accumulator: generally, the oil pressure in the accumulator is the rated value (between the set upper limit and lower limit). When the hydraulic system is working for a long time and the oil pressure drops to the fixed value (lower limit) (still higher than the working oil pressure) due to a very small amount of internal leakage, the electric contact pressure gauge 7 sends a signal to start the oil pump motor to replenish the pressure oil. When the pressure rises to the set upper limit, The electric contact pressure gauge 7 sends a signal and the oil pump motor stops working.
(4) For the description of the hydraulic system, see the Hydraulic System Operation Manual.
(5) When the electric pump fails to work, manual hand pump 24 can be used to supplement the pressure of the accumulator. After the pressure is increased to 14Mpa, operate according to the normal procedure. The hand pump can also be used to open and close the valve without power supply.
(6) In order to inspect and repair the hydraulic system during valve operation, it is only necessary to close stop valves 17 and 18, keep the valves in place (but cannot be used for a long time), and then cut off the power supply for inspection or maintenance.
- Electrical working principle (attached figure)
The power supply ZL of the control system of the machine is assumed by the switching current OMRONH829-3024, the output voltage is DC24V, and the rated current is 4.6A.
Automatic pressure supplement: the oil pump drive contactor signal is from the upper and lower limit contacts of the electric contact pressure gauge. When the pressure in the system is lower than the lower limit setting value, the lower limit contact of the electric contact pressure gauge is connected to J1 for suction, and a self-locking circuit is formed by J1 normally open contact and J2 normally closed point. At this time, the oil pump starts to pressurize the accumulator. When the system pressure increases to the upper limit setting value of the electric contact pressure gauge, the upper limit point is connected, and J2 is connected, The normally closed point of J2 disconnects the J1 circuit. At this time, J2 is self maintained through the normally open point of J1 and J2, and the oil pump stops running, thus keeping the system pressure within the set upper and lower values.
Operation control: K is the change-over switch for local control and remote control. Now take local control as an example: valve opening: 21 press Q2 to open the valve by stopping Q1 to close to 215, 215 turn on 217, and then turn off Q3 to normally close 219. At this time, relay J3 is pulled in, solenoid valve F1 is energized and turned on. High pressure oil enters the upper chamber of the oil cylinder through F1 and presses it down to push the connecting rod to open the valve. During the valve opening process (meaning before it is turned to the position), press Q1 to stop twisting at any time, Make 211 and 215 discontinuous, so that their valves can stop at any position within 0-90 °. Valve closing: 211 normally closes to 215 by stopping the torque 211Q1 and normally closes to 221 by pressing the torque Q3217 and 219. J3 releases to make solenoid valve F1 de energized, 221 and 223 connected, J4 pulled in, solenoid valve F2 energized and connected. At this time, high-pressure oil enters the lower chamber of the oil cylinder through solenoid valve F2, pushes the piston up, drives the connecting rod, and closes it. In the process of closing, The 211-215 can also be cut off at the moment of the stop torque as desired to stop the valve at any position during the closing process. Since the valve opening knob Q2 and the valve closing knob Q3 have formed an interlocking line, during operation, the valve can be directly switched from opening to closing or from closing to opening.
There are two switches at LX1 and LX2, which are respectively installed at the opening and closing positions of the valve. They are used as the indicators of the valve position: the opening to position bumping switch presses LX1 to make 201-225 connected, the XD2 indicator light is on, the closing to position bumping switch presses LX220-227 connected, and the XD3 indicator light is on. When the valve is in the middle position, J3 and J4 are not engaged, so 201 → LX1 is normally closed 229 → LX2 is normally closed 231 → relay J3 is normally closed 233 → relay J4 is normally closed to 235, At this time, the middle indicator is on.
