What Are The Main Contents Of Pneumatic Shut-off Valve Maintenance?

① Check whether the valve head and valve seat are well combined. If there are defects such as scouring groove scratches on the sealing surface, grinding or repair welding processing should be selected according to the degree of defects. Circumferential contact, the valve line is clear;

② Check the surface of the valve stem, it should be smooth and no damage, measure the curvature,

③ Check the joint between the guide sleeve and the valve head for defects such as scratches, burrs, etc. If sandpaper is used, smooth the burrs and the scratched parts so that the movement of the valve head in the guide sleeve is unobstructed;

④ Check the valve body and bonnet for defects such as blisters, cracks, scouring, etc. If there are any defects, the defective parts should be dug out and welded;

⑤ Measure the gap between the valve stem and the metal ring, measure the gap between the packing gland and the packing chamber,

⑥ The diaphragm of the actuator should be free of damage and aging, otherwise it should be renewed. Check whether the length of the measured spring in the free state is consistent with the design size, and whether the end face is parallel. You can tap with a small hammer to hear the sound, which should be clear and no hoarse sound. If it fails to meet the technical requirements, it must be replaced;

⑦ Clean, check and tighten bolts.