Countermeasures for leakage of stuffing box
Due to the leakage of the valve packing box seal and the leakage of the valve body connection seal, which are the key factors causing valve leakage, special attention should be paid to them.
The traditional soft packing seal relies on the axial pressure of the packing gland to generate a certain radial contact stress between the valve stem and the packing, as well as between the packing and the side wall of the packing box, to achieve sealing. Therefore, the axial force of the gland must be quite large, which causes an increase in friction torque and wear between the packing and the valve stem, and the soft sealing packing wears out quickly. Therefore, it is necessary to tighten the gland bolts or replace the packing frequently to ensure a good sealing effect.
By using appropriate packing seals and packing seal combinations, the reliability of valve use can be improved and the service life can be extended. The combination of flexible graphite ring packing has a better sealing effect than using only flexible graphite ring packing. Currently, there are many cases in China where a single flexible graphite ring filler is used; In foreign countries, the use of flexible graphite ring fillers has become popular and has achieved good results.