The working principle of the butterfly valve .
The disc of the butterfly valve is disc-shaped, which rotates around the axis, and the rotation angle is the opening degree of the valve.
2. The use of butterfly valves.
Butterfly valves have developed rapidly in recent years and are widely used in cooling water systems, condensate systems and condensate desalination systems in modern power plants.
Its advantages are: light weight, saving switch strength, simple structure, rapid opening and closing, both cutting off and throttling, and convenient operation, maintenance and overhaul.
3. Classification of butterfly valves.
Butterfly valves can be divided into manual, hydraulic, electric and pneumatic four types according to the transmission mode.
The electric butterfly valve is disintegrated. mainly includes:
①Handle the work ticket, confirm that there is no water and pressure in the pipe, place the valve in the fully closed position, and remove the power connector;
②Remove the connecting bolt of the motor and hang it on the maintenance site;
③Remove the connecting bolts between the flange and the pipe flange, lift the valve body, and be careful not to damage the valve disc;
④Remove the packing gland and take out the packing;
⑤Remove the bottom valve cover, take out the gasket and thrust bearing;
⑥ Remove the fixed taper pin bolts of the shaft and valve packing, take out the valve shaft, take out the valve disc, and mark the flow direction;
⑦ Remove the bolts of the fixed sealing ring on the valve body, and remove the sealing ring.
Maintenance of electric butterfly valve . mainly includes:
(1) Clean the valve shaft and valve sleeve, check the curvature of the valve shaft, the curvature should be within 0.1 mm, and check the wear of the valve sleeve;
②Check the seal ring for scratches and sand holes, clean it with water, and do not touch oil to prevent rubber aging. If necessary, replace with new seals;
③Replace the packing and O-ring;
④Check and clean the valve disc;
⑤Check whether the transmission mechanism is flexible, and check the wear and tear of the transmission gear;
⑥ Replace lubricating oil;
⑦Measure the size of the sealing ring, measure the gap between the valve shaft sleeve and the valve shaft, the gap should be between 0.2-0.3 mm;
⑧ Coat all bolts with lead powder oil.