The oil pump assembly in the APU lubrication system serves what main function?

The function of the oil pump assembly in the Auxiliary Power Unit (APU) lubrication system is primarily to circulate oil to the main bearings and gear trains. This circulation is vital for ensuring proper lubrication, which minimizes friction and wear between moving components within the APU. By delivering oil effectively, the pump helps maintain optimal operating temperatures and enhances reliability, extending the life of the engine parts.

The lubrication process is crucial for the functioning of both bearings and gear trains as these components are subject to high operational stresses. Without adequate oil circulation, there could be increased friction, leading to overheating and potential failure of these critical parts. Therefore, the oil pump assembly plays an essential role in maintaining the health and efficiency of the APU system.