PRACTICAL APPLICATION OF OIL MIST LUBRICATION FOR GEAR DRIVEN MACHINE-TOOL HEADS

Oil Mist consists of small oil particles suspended in the air stream. The air/oil mixture is directed to bearing by fittings, which separate the oil from the air carrier. Two types of fittings, condensing and s pray fittings, are used. The spray fitting creates a turbulent stream of air/oil to form larger particles for lubrication. This article desc ribes oil mist lubrication now being used by some machine tool builder s to lubricate gear-driven heads or spindles that perform metal remova l operations operating at spindle speeds from approximately 400 rpm to 6800 rpm on gear heads and up to high DN values of over 1,000,000 on spindles. (D = Bearing size in m.m.;N = rpm). The previous method of f ogging a gear box to apply oil mist was successful only at higher spee ds that would permit the oil to condense on the bearing or gear. Over lubrication generally was evident in the form of stray mist.