Mechanical seal leakage
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I have machine seals for double-ended reactors, capable of withstanding a maximum pressure of 65 bar and a maximum temperature of 150°C; these reactors are used for carboxylation reactions. The mechanical seal often leaks oil from its upper surface; after it is disassembled for maintenance, the hydrostatic pressure can be maintained, but the hydrodynamic pressure cannot. What are the reasons? Thank you!
I had a pump where this issue occurred; upon inspection, it was found that the compression of the static seal between the shaft sleeve and the impeller was insufficient. Replacing the seal resolved the problem. You might want to check whether it’s the same issue
Check whether the elastic compensation unit has been compressed to its limit, and whether there is any mechanical interference in the friction rings
The static pressure is fine; the dynamic pressure may be leaking, possibly due to issues with shaft play or axial movement
You need to determine where the leak is occurring; if there is no leakage under static pressure, it might be a problem with the O-ring in contact with the shaft
The O-ring in contact with the shaft has two minor radial marks on its cross-section, but they are not obvious. And even after replacing it, it still leaks.
Measured with a dial indicator; the radial value is approximately 70 microns. Axial play has not been measured yet. Upon further inquiry, both the upper and lower sets of moving and stationary ring surfaces show obvious signs of wear, but there is no sensation when touching them – could this be related to it?
The friction ring hasn’t been checked yet; thanks for the reminder!
As the reaction progresses, the medium inside the reactor changes, which affects the operation of the stirring shaft system and can cause radial oscillation (since the shaft system is cantilevered).
The other kettles are fine; the key issue is..
Excessive radial swing, or insufficient pressure from the elastic element of the upper moving ring, could be the causes