Pre-operation preparation:
Before operating the valve, carefully read the operation instructions.
Before operation, the flow direction of gas must be clear, and the valve opening and closing sign should be checked carefully.
3. Check the appearance of the electric valve to see whether the electric valve is damped or not. If it is damped, it should be dried. If other problems are found, it should be dealt with in time and should not be operated with faults.
Four pairs of electric devices that have been out of service for more than three months should check the clutch before starting, confirm the handle's manual position, and then check the insulation, steering and electrical circuit of the motor.
Cautions for operation of electric valves:
1. Verify that the clutch handle is in the corresponding position when starting
If the electric valve is controlled in the control room, turn the switch into REMOTE position, and then control the switch of the electric valve through SCADA system.
3. If the switch is set at LOCAL position by manual control, the switch of the electric valve is operated locally. When the electric valve is opened or closed, it will stop working automatically. Finally, the switch of the running switch is hit in the middle position.
When operating the valve on site, the indication of valve opening and closing and the operation of the valve stem should be monitored, and the opening and closing degree of the valve should meet the requirements.
5 When using on-site operation to completely close the valve, before the valve is closed in place, the electric valve should be stopped and the valve should be closed in place by micro-motion.
Six pairs of valves with adjustable stroke and overtorque controllers should be monitored when they are fully opened or closed for the first time. If the valve switch does not stop at its position, emergency shutdown should be done manually immediately.
7. In the process of opening and closing the valve, when it is found that the signal indicating lamp is wrong and the valve is abnormally noisy, it should stop in time for inspection.
After successful operation, the power supply of the electric valve should be closed.
When operating multiple valves at the same time, attention should be paid to the operation sequence and meet the production process requirements.
When opening large caliber valves with bypass valves, if the pressure difference between the two ends is large, the bypass valve should be opened to regulate the pressure, and then the main valve should be opened: after the main valve is opened, the bypass valve should be closed immediately.
When receiving and receiving pigging balls (pigging devices), the ball valves passing through them must be fully opened.
12 Operating ball valves, gate valves, globe valves and butterfly valves can only be fully opened or closed, and are strictly prohibited for regulating purposes.
During the operation of gate, globe and flat valve, when closing or opening to the upper or lower dead point, turn 1/2 to 1 turn.
Daily maintenance of electric valves:
1. Electric valves should be stored in dry and ventilated rooms, and both ends of the access should be blocked.
2. Electric valves stored for a long time should be inspected regularly to remove dirt and coated with rust-proof oil on the processing surface.
3. After installation, regular inspections shall be carried out. The main inspections are as follows:
(1) Wear condition of sealing surface.
(2) Trapezoidal thread wear of stem and stem nut.
(3) Whether the filler is out of date or not, and if it is damaged, it should be replaced in time.
(4) After the electric valve is repaired and assembled, the sealing performance test should be carried out.
Electric valves in operation, all kinds of valves should be complete and intact. Bolts on flange threads and brackets are indispensable. Threads should be intact and intact. No loosening is allowed. The fastening nuts on the handwheel should be tightened in time if loosening is found, so as not to wear the connection or lose the handwheel and nameplate. If the handwheel is lost, it is not allowed to be replaced by a live wrench. It should be matched in time. Packing glands are not allowed to skew or have no pre-tightening clearance. For electric valves in environments susceptible to rain, snow, dust, sand and other pollutants, the valve stem should be equipped with protective cover. The ruler on the electric valve should be complete, accurate and clear. Lead seals, caps and pneumatic accessories of electric valves should be in good condition. Thermal insulation jacket should be free from depression and crack.
It is not allowed to knock, stand or support heavy objects on electric valves in operation, especially non-metallic electric valves and cast iron electric valves.
