Calculating journal bearing oiling requirements
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Re: Calculating journal bearing oiling requirements
I think he wishes to equalize oil flow to each bearing with restrictors at each of an adequate size that will allow all the needed oil flow at each without oversupplying oil at one or 2 or? resulting in one being oil starved. The problem with that is the fact that the bearing clearance does a fine job of that already with full and "excessive" capacity at the journal. Further restriction on the supply side won't likely turn out well. Just my opinion.. If one or more bearings are starving for oil there is simply not enough oil flow volume to keep up.
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Re: Calculating journal bearing oiling requirements
I thought is was pretty clear about what was originally asked.ELS wrote: ↑Sun Jun 19, 2022 9:27 am I want to calculate the ideal oil flow to a journal bearing, is there a formula or calculator that I can use?
also subquestion related to this; would it be a good idea to then install restriction jets to the oil pump side of the main bearing oiling holes? as to equalize oil flow to the main bearings?
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Re: Calculating journal bearing oiling requirements
Then why did you not directly answer it? You seem to have the answers.Walter R. Malik wrote: ↑Fri Jun 24, 2022 10:42 amI thought is was pretty clear about what was originally asked.ELS wrote: ↑Sun Jun 19, 2022 9:27 am I want to calculate the ideal oil flow to a journal bearing, is there a formula or calculator that I can use?
also subquestion related to this; would it be a good idea to then install restriction jets to the oil pump side of the main bearing oiling holes? as to equalize oil flow to the main bearings?
Re: Calculating journal bearing oiling requirements
Relax man. Share your ideas, share your experiences, that's it. You want to be the thought police.
One can say that they have experienced priority main oiling works better GENERALLY, and from that hypothesize feeding the mains with control jets is the wrong direction. I don't really know why. We'd have to TEST that all kinds of different ways to find out.
One can say that they have experienced priority main oiling works better GENERALLY, and from that hypothesize feeding the mains with control jets is the wrong direction. I don't really know why. We'd have to TEST that all kinds of different ways to find out.
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Re: Calculating journal bearing oiling requirements
Restricting the oil supply to the bearings is a bad idea. You cannot over-supply a bearing with oil; it will self
meter based on bearing clearance and diameter.
However, it is possible to under-supply a bearing if the flow volume is inadequate.
If we calculate the flow area for each bearing, the total area must be less than the main
oil galley area. Some engines have been designed with stepped oil galley areas, not to reduce
oil flow volume, but to ensure there is sufficient volume to allow oil flow to the furthest
lubrication point.
Oil pressure does not only affect oil flow volume at the bearings, but also at the camshaft.
Excess oil pressure is not a problem unless it produces oil foaming and aeration.
Oiling is more than mere oil volume. Oil viscosity, temperature and fluid density must be considered.
meter based on bearing clearance and diameter.
However, it is possible to under-supply a bearing if the flow volume is inadequate.
If we calculate the flow area for each bearing, the total area must be less than the main
oil galley area. Some engines have been designed with stepped oil galley areas, not to reduce
oil flow volume, but to ensure there is sufficient volume to allow oil flow to the furthest
lubrication point.
Oil pressure does not only affect oil flow volume at the bearings, but also at the camshaft.
Excess oil pressure is not a problem unless it produces oil foaming and aeration.
Oiling is more than mere oil volume. Oil viscosity, temperature and fluid density must be considered.