Preparation before electric valve operation

Preparation before operation:

1 Read the operating instructions carefully before operating the valve.

2 Be sure to know the flow direction of the gas before operation, and pay attention to check the valve opening and closing signs.

3. Check the appearance of the electric valve to see if the electric valve is damp. If it is damp, it should be dried. If there are other problems, it should be dealt with in time, and it should not be operated with faults.

4 For electric devices that have been out of use for more than 3 months, the clutch should be checked before starting. After confirming that the handle is in the manual position, check the insulation, steering and electrical lines of the motor.

Precautions for electric valve operation:

1 When starting, make sure the clutch handle is in the corresponding position

2 If the electric valve is controlled in the control room, turn the switch to the REMOTE position, and then control the switch of the electric valve through the SCADA system.

3 If it is controlled manually, put the transfer switch in the LOCAL position, and operate the switch of the electric valve on the spot. When the electric valve is opened or closed in place, it will automatically stop working, and the operation transfer switch will be turned to the middle position.

4 When using the field operation valve, the valve opening and closing indication and the operation of the valve stem should be monitored, and the valve opening and closing degree should meet the requirements.

5 When using on-site operation to fully close the valve, before the valve closes in place, stop the electric valve closing, and use micro-motion to close the valve in place.

6 For the valve after the stroke and over-torque controller has been set, when the valve is fully opened or fully closed for the first time, attention should be paid to monitoring its control of the stroke.

7 In the process of opening and closing the valve, if it is found that the signal indicator light is wrong and the valve has abnormal noise, it should be stopped in time for inspection.

8 After the operation is successful, the power supply of the electric valve should be turned off.

9 When operating multiple valves at the same time, pay attention to the operation sequence and meet the production process requirements.

10 When opening a larger-diameter valve with a bypass valve, if the pressure difference between the two ends is large, the bypass valve should be opened first to adjust the pressure, and then the main valve should be opened: After the main valve is opened, the bypass valve should be closed immediately.

11 When sending and receiving pigging balls (devices), the ball valves it passes through must be fully opened.

12. The ball valve, gate valve, globe valve and butterfly valve can only be fully opened or fully closed, and it is strictly forbidden to be used for adjustment.

13 During the operation of gate valve, globe valve and flat valve, when it is closed or opened to the top dead center or bottom dead center, it should be rotated 1/2 to 1 turn.

Daily electric valve maintenance:

1. The electric valve should be stored in a dry and ventilated room, and both ends of the passage must be blocked.

2. Electric valves that have been stored for a long time should be checked regularly, the dirt should be removed, and anti-rust oil should be applied to the processing surface.

3. After installation, regular inspections should be carried out. The main inspection items:

(1) The wear of the sealing surface.

(2) The wear of the trapezoidal thread of the stem and stem nut.

(3) Whether the packing is outdated and invalid, if damaged, it should be replaced in time.

(4) After the electric valve is repaired and assembled, the sealing performance test should be carried out.

For the electric valve in operation, various valve parts should be complete and intact. Flange threads and bolts on the bracket are indispensable, the threads should be intact, and no loosening is allowed. If the tightening nut on the handwheel is found to be loose, it should be tightened in time to avoid abrasion of the connection or loss of the handwheel and nameplate. If the handwheel is lost, it is not allowed to replace it with an adjustable wrench, and it should be completed in time. Packing glands are not allowed to be skewed or have no preload clearance. For electric valves in environments that are easily contaminated by rain, snow, dust, sand and other pollutants, the valve stem should be equipped with a protective cover . The scale on the electric valve should be kept complete, accurate and clear. The lead seal, cap, and pneumatic accessories of the electric valve should be complete and intact. The insulation jacket should be free of dents and cracks.

It is not allowed to knock, stand or support heavy objects on the electric valve in operation; especially non-metal electric valve and cast iron electric valve, it is even more forbidden.