Common valve failures and solutions:
1. Valve body leakage:
Causes:
1. The valve body has blisters or cracks,
2. The valve body is cracked during repair welding.
Treatment:
1. Polish the suspected cracks and etch them with 4% nitric acid solution. If there are cracks, they will be revealed.
2. Excavate and repair cracks.
2. The thread of the valve stem and its matching nut is damaged or the valve stem head is broken or the valve stem is bent:
Causes:
1. Improper operation, excessive force on the switch, failure of the limit device, and failure of over-torque protection.
2． The thread fit is too loose or too tight.
3. Too many operations and too long service life.
Processing:
1. Improve the operation and do not use excessive force; check the limit device and the over-torque protection device.
2． The materials should be selected appropriately and the assembly tolerances should meet the requirements.
3. Replace spare parts.
3. Leakage at the valve cover joint surface:
Cause:
1. The bolt tightening force is not enough or the tightening force is off.
2． The gasket does not meet the requirements or the gasket is damaged.
3. The joint surface is defective.
Processing:
1. Retighten the bolts or make the door cover flange clearance consistent.
2． Replace the gasket.
3. Disassemble and repair the door cover sealing surface.