Abstract: The lean amine liquid pump in a unit is a highspeed pump, and the large amount of foaming oil in the oil tank leads to the continuous decrease of oil pressure during the operation of the equipment, causing great hidden dangers to the safe operation of the equipment, the oil pressure drop was not improved before the foaming condition was eliminated, and the oil pressure returned to normal after the foam was eliminated, judge the reason of oil pressure drop is that the foam produced in the lubricating oil is too much and is not easy to burst. Through the analysis of the relationship between temperature, oxidation, pH value and foaming tendency, foam stability, the harm of oil pressure drop caused by foaming was solved, and the improvement measures for operation and maintenance were put forward.

Key words: lean amine, lubricating oil pressure, lubricating oil temperature, oxidation; pH value, blisteringtendency, foam stability