Valve electric device operation method and maintenance

Valve electric device operation method

First, preparation before operation

1.1 Read the operating instructions carefully before operating the valve.

1.2 Be sure to understand the flow direction of the gas before operation. Pay attention to check the valve opening and closing mark.

1.3 Check the appearance of the electric valve to see if the electric valve is damp. If there is moisture, it should be dried; if there are other problems, it should be handled in time, and it must not be operated with failure.

1.4 For electric devices that have been deactivated for more than 3 months, check the clutch before starting. After confirming that the handle is in the manual position, check the insulation, steering and electrical wiring of the motor.

Second, electric valve operation precautions

2.1 When starting, confirm that the clutch handle is in the appropriate position.

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

2.3 If the manual control, the switch is placed in the LOCAL position, the switch of the electric valve is operated on the ground, when the electric valve is opened or closed, it will automatically stop working, and finally the running change switch is hit to the middle position.

2.4 When using the valve in the field, the valve opening and closing instruction and the valve stem operation should be monitored. The valve opening and closing degree should meet the requirements.

2.5 When using the on-site operation to fully close the valve, before the valve is closed, stop the electric shut-off valve and use the micro-motion to close the valve.

2.6 For the valve after the stroke and over-torque controller is set, when the valve is fully opened or closed for the first time, it should be monitored to monitor the stroke. If the valve switch does not stop, the manual emergency stop should be taken immediately.

2.7 During the process of opening and closing the valve, if the signal indicator light is wrong and the valve has abnormal noise, it should be stopped and checked in time.

2.8 The power of the electric valve should be turned off after successful operation.

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

2.10 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, then the main valve should be opened: after the main valve is opened, the bypass valve should be closed immediately.

2.11 When the clearing ball is sent and received, the ball valve that passes through it must be fully open.

2.12 Operation of ball valve, gate valve, globe valve and butterfly valve can only be fully open or fully closed. It is strictly for adjustment.

2.13 During the operation of the gate valve, globe valve and flat valve, when closing or opening to the top dead center or bottom dead center, it should be rotated 1/2 to 1 turn.

Valve electric device maintenance

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

2. The electric valve for long-term storage should be inspected regularly to remove dirt and apply anti-rust oil on the processing surface.

3. After installation, it should be inspected regularly, mainly for inspection items:

(1) Wear of the sealing surface.

(2) Trapezoidal thread wear of the 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 shall be carried out.

The electric valve in operation, all kinds of valve parts should be complete and intact. The flange threads and the bolts on the bracket are indispensable, the threads should be intact and no looseness is allowed. The tightening nut on the hand wheel should be tightened if it is loose, so as not to wear the joint or lose the handwheel and nameplate. If the handwheel is lost, it is not allowed to replace it with a wrench. It should be timely. The packing gland is not allowed to be skewed or has no pre-tightening clearance. For electric valves in environments that are susceptible to contamination by rain, snow, dust, sand, etc., the valve stem should be fitted with a protective cover. The scale on the electric valve should remain complete, accurate and clear. Lead seals, caps, pneumatic accessories, etc. for electric valves should be completed. The insulation jacket should be free from dents and cracks.

It is not allowed to hit, stand or support heavy objects on an operating electric valve; especially non-metallic electric valves and cast iron electric valves are prohibited.