Centrifugal pump mechanical seal leakage causes operation and installation errors

First, the normal operation of a sudden leak. Centrifugal pumps in operation suddenly leaking a few are due to normal wear and tear or has reached the end , but mostly due to large changes in working conditions , operation or maintenance caused by improper .
1 , taking the time , cavitation or longer hold pressure , resulting in seal damage ;
2 , the actual output of the pump is too small, a large number of medium circulation pump , heat build-up , causing the gasification medium , resulting in seal failure ;
3, the return flow is too large , causing suction tube side of the container ( tower, kettle , pot, pool ) at the bottom dregs , damaged seals ;
4 , for a long time outage, restart without manual turning , friction due to adhesion and tearing sealing surface ;
5, the corrosive medium , the polymerizable , gumming material increased;
6, the dramatic changes in the ambient temperature ;
7 , or adjustment of operating conditions change frequently ;
8 , such as a sudden power outage or downtime . Centrifugal sudden leak in normal operation , if not in time, often lead to more accidents or loss shall be seriously and take effective measures .
Second, pump mechanical seal Overhaul Mistakes
1 , the greater the amount of compression spring seal better. In actual fact , the spring compression excessive friction can cause rapid wear , instantly burning ; excessive compression of the spring to lose the ability to adjust the ring face , resulting in seal failure.
2 , the sealing ring diagram tighter, the better . In fact, ring seals tight harm than good. First exacerbate inter- ring and sleeve wear, premature leakage ; Second, increasing the axial adjustment ring , the resistance movement , frequent changes in operating conditions can not make timely adjustments ; Third spring excessive fatigue easily damaged ; four is to make the ring seal deformation, affecting the sealing effect.
3, the stationary ring seals tight as possible . Stationary ring seals basically at a standstill , the effect will be relatively tight seal better, but too tight is harmful. One cause static ring seals due to excessive deformation, affecting the sealing effect ; Second, the majority of graphite stationary ring material , generally more brittle , excessive force can easily cause fragmentation ; three is to install , difficult to remove , easy to damage the stationary ring .
4 , impeller lock nut tight as possible . Mechanical bolt seal leakage , the leakage between the sleeve and the shaft ( shaft between the leak ) is relatively common . Generally, the impeller shaft between the leak is not locking the lock master , in fact, lead to leakage between axes many factors , such as the failure of inter-axis pad , offset , there are impurities between axes , with the shaft and sleeve at a larger shape bit error , the contact surface damage , there is a gap between the shaft parts , threaded shaft is too long , and this will lead to leakage between the shafts . Lock nut locking pad between axes can only lead to excessive premature failure , contrary moderate lock locked mother , so that the shaft between the pads always maintain a certain degree of compression flexibility in operation will be automatically timely lock nut locking , so that the shaft is always in a good inter- the sealed state .
5 , the new better than the old . In contrast, using the new mechanical seal better than the old , but the new mechanical seal quality or choice of material is not the time , with the larger size of the error will affect the sealing effect ; and permeability in the polymerization medium, the stationary ring without excessive wear, or not to replace as well. Because static ring stationary ring seat for a long time in a quiescent state , the polymer and impurities deposited as a whole, played a good seal.
6 , do not split overhaul than good . Once the mechanical wire seals leakage will be eager to overhaul , in fact , sometimes sealed and not damaged , simply adjust the working conditions or the seals can be adjusted to eliminate leakage. This way to avoid waste and can verify their fault judgment ability , and accumulated experience in maintenance to improve the quality of maintenance .