How to correctly repair welding bellows mechanical seal
1, the greater the amount of spring compression, the sealing effect will be better. In fact, excessive compression of the spring can cause wear of the friction pair and rapid instantaneous combustion; the over-compression spring loses the ability to adjust the end face of the moving ring, resulting in failure of the seal.
2, the tighter the dynamic seal diagram, the better. In fact, the dynamic ring seal is too tight and harmful. One is to accelerate the wear and tear, premature leakage of sealing rings and bushings; the second is to increase the dynamic axial adjustment of resistance movements, and cannot be adjusted timely when working conditions change frequently; third, spring fatigue is easily damaged; and fourthly, the dynamic ring seal ring is used. Deformation, affect the sealing effect.
3, the tighter the static ring seal, the better. The static ring seal is basically at a standstill, relatively tight seal effect will be better, but too tight and harmful. One is due to excessive deformation caused by the static seal, affecting the sealing effect; Second, the static ring material is mostly graphite, generally more brittle and vulnerable to excessive pressure caused by fragmentation; Third, the installation, removal difficult, very easy to damage the static ring.
4, impeller locking nut fastened. Leakage of the mechanical seal of the welded bellows, leakage between the sleeve and the shaft (leakage between shafts) is common. Under normal circumstances, the shaft-to-shaft leakage is not caused by the imperial lock of the impeller lock. In fact, the shaft leakage occurs due to the failure of the shaft pad, the displacement of the shaft, the presence of impurities on the shaft, and the larger misalignment of the shaft axis with the sleeve axis. Surface damage, gaps between components on the shaft, too long first line leads to leakage between shafts. Excessive lock master locks will only lead to premature failure of the inter-axis pad, while a moderate lock master will keep the inter-axle pad pressure at a certain operating flexibility. The lock mother will automatically lock the correct time, so that the shaft is always in a good seal status.
5, The new one is better than the old one. Relatively speaking, the effect of the new welded bellows mechanical seal is better than the old, but the quality of the new welded bellows mechanical seal or the choice of material is no time, with a larger size error will affect the sealing effect; in the polymeric and permeable media In the middle, the static ring is not excessively worn or replaced. Since the stationary ring is in a stationary state for a long period of time, the polymer and the impurities are deposited as a whole, which provides a good sealing effect.
6, dismantling is better than not dismantling. Once the welding bellows mechanical seal leakage is actually eager to repair, sometimes closed and not broken, just adjust the working conditions or properly adjust the seal to eliminate the leakage. This not only can avoid waste but also can verify its ability to judge fault repair experience accumulation and improve the quality of inspections.