Seeking help with knowledge related to mechanical seals
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This post was last edited by liuqun06092863 on 2015-6-11 13:36. Dear experts, the general description of mechanical seals is as follows: “It is a device that prevents fluid leakage, consisting of at least one pair of end faces perpendicular to the axis of rotation, which remain in contact with each other and slide relative to one another under the action of fluid pressure and the elastic force (or magnetic force) of a compensation mechanism, along with the assistance of auxiliary seals.” ” It feels so empty. (Referring to the seal fluid at the water level,) I would like to ask: 1. How is the liquid film in a mechanical seal formed? 2. What is the direction of water flow within this liquid film after it is formed? (I’ll use PLAN32 as an example.) In my understanding, before the pump starts operating, water enters between the outer ends of the rotating and stationary rings; under the effect of centrifugal force, wouldn’t this water be flung out? So, how does water get into the space between the rotating and stationary rings after the pump starts, and will it still be flung out once it’s there? Actually, I just want to ask how water gets into the sealed end face, what is the direction of its flow once it’s inside, and how it removes the heat generated at that end face.
This is how I understand it: 1. When it rotates, water seeps in through the gaps in the end surfaces； 2. If there is no major leakage, this layer of liquid film will remain between the end faces
The mechanical seal contains a pumping ring that rotates along with the pump shaft, enabling the sealing fluid to flow in a directed manner and circulate, thereby carrying away heat
What you said is incomplete, and it’s not what PLAN32 requires. But still thank you :)
Generally, for PLAN32, the flushing water pressure only needs to be 0.1~0.2 MPa higher than that in the sealing chamber. Our system uses a circulating sealant for flushing and cooling; when the pump is operating, an external pressure source balances the pressure of the fluid inside the pump and provides the necessary power to drive the sealant into the mechanical seal area, thereby achieving cooling, lubrication, and sealing effects. This is my personal opinion; please point out any mistakes.