Minor modification to the bearing housing to address lubricant leakage from the labyrinth ring
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The bearing housing at the non-drive end of the new standby pump is cooled by a fan; the shaft and bearing housing oil seals are of the labyrinth seal type, made by INPROSEAL. Since the fan is located above the breather valve (exhaust valve) of the bearing box, air enters the bearing box through the breather valve, creating a negative pressure inside it. This causes the lubricating oil to seep out through the labyrinth ring, and the fan then blows this oil all over the bearing box. Although this issue does not affect functionality, it does impact the working environment. Later, the breather valve was raised to resolve this issue; as shown in the figure, it doesn’t look very aesthetically pleasing. Do any of you have any better suggestions?
Aesthetics aren’t important; functionality is what truly matters; P:victory:
Personally, I think it’s not clear whether this situation affects usability; if it doesn’t, there’s no need for the original poster to worry so much. Try to modify it again – it’s costly and time-consuming, and the modification of the stopped fans may also affect production. Of course, if there is a truly viable solution and the repair costs are not too high, you can give it a try. ;P
Oh, I see now. The reason is that the outlet of the oil vapor exhaust pipe is affected by the fan during operation, increasing the amount of exhaust. Making this change can reduce the air volume at the exhaust opening, thereby decreasing evaporation. Not bad :)
The bearing housing on the non-drive side of the oil transfer pump is shown in the figure below
The gland area can be modified to use a labyrinth seal plus a skeleton oil seal
Block a few of the ventilation holes on the breather valve, leaving one or two; when installing, face those holes away from the direction of the wind. It’s just a small suggestion that you might want to try
It is not negative pressure that forms inside the bearing box, but rather negative pressure is created on the surface of the bearing box due to the action of the fan. Under the effect of this pressure difference, oil and gas escape from the oil seal location.
The purpose of this modification is to prevent fan air from entering the bearing box through the breather valve; everything else remains unchanged, so that the lubricating oil does not leak out； If the fan creates negative pressure on the surface, will oil still seep through after my modification (since there is still a negative pressure environment outside the labyrinth ring)?
It’s hard to say; previously, Ford used bearing isolators in one of its vertical pumps, and the oil kept coming out from the isolator at the top, reaching as far as the fan in the exhaust cap.