Axial fracture of the mechanical seal in ultra-cold water pumps
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The medium temperature is around 80°C; yesterday the first seal broke, and three more have broken since then. The shaft is not bent, and there are no issues with the perpendicularity of either the stationary or rotating ring. When the first seal broke, it was found that there was wear on the ring at the pump’s end cover; increasing the compression by one millimeter resolved the wear issue, but the seal still broke
Water at 80 degrees Celsius has very poor lubricity; the liquid film between the rings is unstable, which leads to an increase in torque. Fractures occur at the point where force is transmitted from the lugs, so the rotating ring is replaced with one that has grooves, similar to those in the C8BKC series. Or replace the material of the sealing ring to enhance flushing and cooling
This post was last edited by Frozen Desert on 2019-3-6 at 10:47; it’s a dual-machine seal with oil added in between. The detection of oil emulsification was the first sign of a secret leak. There is no instruction manual, but it seems that the self-cleaning procedure involves Plan11+Plan52. At the moment, all other pumps are working fine; only this one breaks down after just three uses.
The current model of the mechanical seal is C8B-50G
Well, acidic water. I just did a search – the C8BKC structure you mentioned is pretty much the same as the C8B structure, right?
It is usually caused by the instability of the liquid film
How should this be solved? Previously, it was also sealed in this way, and it worked just fine
The same; there are just a few hydrodynamic pressure grooves on the end face
Yours is a dry gas seal; look at the diagram – there are such grooves on the ring surface