Oil Pressure
The oil pressure generated in most engines should be about 10 psi per every 1000 revolutions per minute (rpm), peaking around 55-65 psi.
Local pressure (at the crankshaft journal and bearing) is far higher than the 50, 60 psi &c. set by the pump’s relief valve, and will reach hundreds of psi. This higher pressure is developed by the relative speeds in feet per second (not RPM or journal size directly) of the crankshaft journal itself against the bearing, the bearing width (to the closest pressure leak), oil viscosity, and temperature, balanced against the bearing clearance (the leakage rate).
All pump pressure does is “fill in the hole” and refresh the oil in the annular space faster than the leak expels it. This is why low-speed engines have relatively large journals, with only modest pump size and pressure. Low pressure indicates that leakage from the bearings is higher than the pump’s delivery rate.
Read more about this topic: Oil Pump (internal Combustion Engine)
Famous quotes containing the words oil and/or pressure:
“As artists they’re rot, but as providers they’re oil wells; they gush. Norris said she never wrote a story unless it was fun to do. I understand Ferber whistles at her typewriter. And there was that poor sucker Flaubert rolling around on his floor for three days looking for the right word.”
—Dorothy Parker (1893–1967)
“Destiny is an absolutely definite and inexorable ruler. Physical ability and moral determination count for nothing. It is impossible to perform the simplest act when the gods say “no.” I have no idea how they bring pressure to bear on such occasions; I only know that it is irresistible.”
—Aleister Crowley (1875–1947)