The mechanical seal of the centrifugal pump wears out frequently
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The mechanical seals used in the centrifugal pumps at the company keep breaking down. The fluid stored in the tanks is a viscous liquid that tends to crystallize; leakage occurs whenever the pumps are in operation. When they’re not running, the leaked fluid can easily crystallize. Even when there’s no leakage, leaks still occur from the inside. I’m not sure what’s causing this problem; I hope the expert can give some advice. Thank you so much!
Replace the PTFE O-ring.
The leakage of material from the mechanical seal indicates that the pressure within the seal is low; under normal conditions, the pressure in the seal should be slightly higher than the pressure of the pump itself. I’m not sure whether your mechanical seals are self-circulating or externally connected. In the case of self-circulation, it is necessary to consider the purity of the medium itself, as well as whether the material used for the mechanical seal can withstand the friction caused by that medium. There’s also the issue of the O-ring; when a mechanical seal is damaged, it’s either due to a damaged O-ring or wear on the sealing surfaces. Consider these two aspects to see if the problem can be resolved.
In my opinion, a mechanical seal is not appropriate for this situation; instead, a packing seal or an oil seal should be used.
The medium being transported is prone to crystallization; it is advisable to use a combined sealing system, combining a mechanical seal with a nitrogen seal.
The mechanical seal was not selected properly. Try a different sealing type; have the sealing manufacturer help you choose one.
It is estimated that the machine seal selected is not appropriate; this type is recommended. For such media, an auxiliary seal is very important and must be used; for materials that tend to crystallize, steam insulation is a good option.
There are a wide variety of mechanical seals used in pumps, with different models, but there are mainly five leakage points: 1) the seal between the shaft sleeve and the shaft； 2) Sealing between the rotating ring and the shaft sleeve ； 3) Sealing between the rotating and stationary rings ； 4) Sealing between the stationary ring and the stationary ring seat ； 5) Sealing between the sealed end cover and the pump body. Because the medium in your storage tanks is a viscous liquid that tends to crystallize. It is recommended to replace the PTFE seal ring.
Thank you to all the experts above; I appreciate it very much!