I Overview of functions of electro-hydraulic actuator
This electro-hydraulic actuator has three sets of operating functions: Local control cabinet operation,Remote control operation and emergency hand pump operation:
1. Remote control：
1）Double-acting FL: The actuator performs an open (or close) valve operation by opening (or closing) the valve signal.
2）Single-acting FC(or FO) : the valve is opened (or closed) by the valve opening (or valve closing) signal. When the systemen counters an emergency state such as loss of power and loss of signal, the accumulator in the electro-hydraulic actuator will release oil pressure and quickly and automatically close (or open) thevalve without instructions.
3）Intelligent valve regulation and control: in the condition that the valve opening degree and stage speed are required to be adjusted, the actuator is equipped with servo proportional valve,displacement sensor and PLC. Under the control signal of 4 ~ 20mA, the actuator's stroke location of 0° ~ 90° can be adjusted.
Note:The electro-hydraulic actuator itself is a closed-loop control system,which can set the following parameters on the actuator body: valve opening/closing speed, working pressure of hydraulic system, delay alarm time of self-protection device, etc.
2. Local control cabinet operation：
The control cabinet panel is equipped with buttons for emergency local operation, indicator light for valve position,alarm light for valve failure and emergency cut-off switch.
The indicator of valve position shows the current state of the valve, and the opening valve light is on, indicating that the valve is in the open state.Similarly, the closing valve light is on, and the valve is in the closed state.Valve position fault light: indicating valve stuck or hydraulic system failure, need maintenance.
Emergency cut-off switch: press this switch, the control cabinet will automatically cutoff the power supply, making the system stop working instantly. At this point,the actuator is reset under the action of the spring.
Valve opening button: press this switch and the valve will be opened in place.
Valve closing button: press this switch and the valve will be closed in place.
Local/remote switch handle: switch to local operation file, and the valve can be operated in place; Switch to remote file, you can control the valve by remote signal.
3. Emergency hand pump operation：
This electro-hydraulic actuator is equipped with an importedemergency hand pump. Switching to the operation mode of emergency hand pump, itcan open or close the valve by mechanical means in the case of power loss ofthe system.
4. Mechanically locked valve
After the valve opening/closing operation is completed, close the locking globe valve at the oil inlet and outlet on both sides of the actuator to mechanically lock the actuator to maintain the current valve state. No matter how the electric control cabinet or the hand pump system on the actuator is operated, the current valve state cannot be changed. This function can prevent the wrong operation on site. If normal operation is to be resumed, open the lock stop valve and the control cabinet and the hand pump system will be restored.
II Three - dimensional structure composition of electro - hydraulic actuator
III Working principle of hydraulic control ofelectro-hydraulic actuator
1. Double acting FL series electro-hydrauli cactuators
Function description of double-acting FL series electro-hydraulic actuator:
1）Remote control hydraulic closing valve: close the b1 and b2 stop valves and open thea1 and a2 stop valves. Electrify the electromagnetic reversing valve 11(M2) to connect the 11 left position of the electromagnetic reversing valve to the system,the accumulator releases high pressure and high flow hydraulic oil, the piston of the hydraulic actuator moves quickly to the left, and the valve closes quickly.
2）Accumulator automatically fill pressure: when the accumulator release the high pressureoil, minimize the system pressure below the pressure relay setting value, the motor start working to drive hydraulic pump oil supply pressure, system pressure began to rise and accumulator energy storage, when the system pressure to achieve maximum pressure relay setting, automatic cut off the source,hydraulic pump to stop the oil supply.
3）Remote control hydraulic opening valve: when the solenoid reversing valve 11(M1) is energized so that its right position is connected to the system, the accumulator releases high pressure and high flow oil, the hydraulic actuator piston moves to the right quickly, and the valve opens quickly. Intelligent operation of valve: the actuator is equipped with servo proportional valve, angular displacement sensor and PLC. Under the control signal of 4~20mA, the actuator can realize the position adjustment of stroke from 0° to 90°.
4）When both M1 and M2 lose power, the electro-hydraulic actuator has the function of power loss and position protection;
5）Manual operation: open a1, a2, b1 and b2 stop valves,connect the reversing valve of the hand-operated pump system to the left, shake the handle of the hand-operated pump, move the piston of the hydraulic actuator to the right, and open the valve; Conversely, the hand pump system to the right of the reversing valve into the system, the valve closed.
2、 Single acting FC (or F0)series electro hydraulic actuator
Function description of single action FC (or F0) series electro hydraulic actuator：
1）Remote control hydraulic opening valve:close the b1 and b2 stop valves and open the a1 and a2 stop valves. Electrify the electromagnetic reversing valve 11(M2) to connect the 11 left position ofthe electromagnetic reversing valve to the system,the accumulator releases high pressure and high flow hydraulic oil, the piston of the hydraulic actuator moves quickly to the right, and the valve opens quickly.
2）Accumulator automatically fill pressure: when the accumulator release the high pressure oil, minimize the system pressure below the pressure relay setting value, the motor start working to drive hydraulic pump oil supply pressure, system pressure began to rise and accumulator energy storage, when the system pressure to achieve maximum pressure relay setting, automatic cut off the source, hydraulic pump to stop the oil supply.
3）Remote control hydraulic closing valve: when the solenoid reversing valve 11(M1) is energized so that its right position is connected to the system, the accumulator releases high pressure and high flow oil, the hydraulic actuator piston moves to the left quickly, and the valve closes quickly. Intelligent operation of valve: the actuator is equipped with servo proportional valve, angular displacement sensor and PLC. Under thecontrol signal of 4~20mA, the actuator can realize the position adjustment of stroke from 0° to 90°.
4）Manual operation: close a1 and a2 stop valves, open b1 and b2 stop valves, connect the reversing valve of the hand-operated pump system to the left, shake the handle of the hand-operated pump, move the piston of the hydraulic actuator to the left, and close thevalve; Conversely, the hand pump system to the right of the reversing valve into the system, the valve open.
IV Electrohydraulic actuator output torque and dimensions
1. Conventional torque electro-hydraulic actuator
2. Large torque electro-hydraulic actuator
V Principle of electrical control of electro hydraulic actuator mechanism
1. Control box panel diagram
2. Wiring diagram
3. Control circuit diagram
Note:This scheme is the basic configuration of this series of products. Our company can customize the configuration according to customers' specific requirements and special working conditions, so as to fully meet customers' different needs.
F4-Y-DA/HPU series electro-hydraulic actuator（Download）
