(1) Failure cause: (Valve leakage is the largest proportion of packing)

1. Packaging selection is wrong, not resistant to moderate corrosion, not resistant to high pressure or vacuum valve, high temperature or low temperature use:

2. Improper packaging and installation, defects such as changing small to large, bad screw wrapping, loose fastening and so on:

3. The caulk has outlived its service life, aged and lost elasticity

4. Valve stem precision is not high, bending, corrosion, wear and other defects.

5. Insufficient number of packing rings, not tight gland pressure:

6. Glands, bolts, and other areas are damaged and cannot be compressed:

7. Improper operation, excessive use of force, etc. :

8. Deflected glands, the gap between the glands and the valve stem is too small or too large, resulting in valve stem wear and packaging damage.

(II) Troubleshooting method:

1. The material and type of filling should be selected according to the working conditions:

2. Properly install the packaging in accordance with relevant regulations, the packaging shall be placed and compressed one by one, and the connector shall be 30°C or 45°C:

3. Long-term use, aging or damaged packaging should be replaced in time:

4. After the valve stem is bent or worn, straighten and repair it. If the damage is serious, it shall be replaced in time:

5. The packaging should be installed according to the specified number of turns, the glands should be tightened symmetrically and evenly, and the compression sleeve should have a pre-tightening gap of more than 5mm:

6. Damaged glands, bolts and other parts should be repaired or replaced in time:

7. The operation procedure shall be followed, except for the impact of the hand wheel, and the operation shall be carried out at a constant speed and normal force:

8. Gland bolts should be tightened evenly and symmetrically. If the gap between the gland and the stem is too small, the gap should be increased appropriately: the gap between the gland and the stem should be too large and should be replaced.