Leakage treatment of valve packing
Improper operation, excessive force, etc;
The gland, bolts and other parts are damaged, which makes the gland unable to be pressed tightly;
The gap between the gland and the valve stem is too small or too large, resulting in valve rod wear and packing damage.
The packing is not installed properly, and there are some defects, such as replacing the big with the small, the spiral winding joint is not good, and the tightening is loose;
Packing selection is not correct, not resistant to medium corrosion, not resistant to valve high pressure or vacuum, high temperature or low temperature use;
4. The precision of the valve stem is not high, there are bending, corrosion, wear and other defects; 5. The number of packing rings is insufficient, and the gland is not compacted;
Methods of prevention and elimination:
The material and type of packing should be selected according to the working conditions;
The fillers with long service life, aging and damage shall be replaced in time;
Damaged gland, bolt and other parts shall be repaired or replaced in time;
Besides the impact handwheel, it should be operated with constant speed and normal force;
The valve rod should be straightened and repaired after bending and wear, and the seriously damaged valve rod should be replaced in time;
The packing should be installed correctly according to the relevant regulations. The packing should be placed and compacted one by one, and the joint should be at 30 ℃ or 45 ℃;
The packing should be installed according to the specified number of turns, the gland should be tightened symmetrically and evenly, and the pressing sleeve should have a pre tightening clearance of more than 5mm;
The gland bolts should be evenly and symmetrically tightened. If the clearance between the gland and the valve stem is too small, the clearance should be appropriately increased; if the clearance between the gland and the valve stem is too large, it should be replaced.