Cause Analysis:
1. The packing gland is not tightly pressed.
2. The filler becomes invalid due to long-term use or improper storage.
solution:
1.Tighten the nuts evenly to compress the packing.
2. Replace the packing.
2. Leakage between the sealing surfaces.
Cause Analysis:1. There is dirt on the sealing surface.
2. The sealing surface is damaged.
solution:
1. Remove dirt and debris.
2. Reprocessing or replacement.
3. Leakage at the connection between the valve body and the valve cover.
Cause Analysis:1. The connecting bolts are not evenly tightened.
2. The flange sealing surface is damaged.
3. The gasket is cracked or failed.
solution:
1. Tighten evenly.
2. Re-dressing.
3. Replace with new gaskets.
4. The handwheel is not flexible or the valve disc cannot be opened and closed.
Cause Analysis:1. The packing is too tight.
2. Packing pressure plate and pressure sleeve device are skewed.
3. The stem nut is damaged.
4. The thread of the stem nut is severely worn or broken.
5. The valve stem is bent.
solution:
1. Properly loosen the nut on the packing pressure plate.
2. Correct the packing pressure plate.
3. Disassemble and trim threads and remove dirt.
4. Replace the stem nut.
5. Correct the valve stem.