Measurement of Piston Ring Oil Film Thickness in an Operating Engine

Abstract

Oil film thickness of the piston ring under actual operating conditions was measured in a diesel engine (D × S = 140 × 152 mm), using electrodes with aluminum oxide layers embedded in the top ring. As a result, following characteristics have been found:

(1) The oil film thickness under normal operating conditions was considerably thinner than the theoretical value.

(2) Nevertheless, the thickness agreed well with hydrodynamic theory if oil was adequately supplied.

(3) The top ring always varied its inclination angle against the cylinder wall which affected the oil film formation.

Presented as an American Society of Lubricalton Engineers paper at the ASME/ASLE Lubrication Conference in Washington, D. C., October 5–7, 1982

Notes

Presented as an American Society of Lubricalton Engineers paper at the ASME/ASLE Lubrication Conference in Washington, D. C., October 5–7, 1982