Analysis of lubricating characteristics of main bearing on free fall lifeboats
SHI Jun;DAI Chenglong;ZHANG Shundong;Zhenjiang Siyang Diesel Engine Manufacturing Co.Ltd.;School of Energy and Power Engineering,Jiangsu University of Science and Technology;
When a lifeboat falls into water,great impact pulses are created. They are transmitted from the body to the base and engine block and finally to the power units. These impulses will have great effect on the safety and reliability of the crankshaft. A 380 J diesel engine with 3 cylinders is used as the main engine of the lifeboat studied in this paper. With multi-body dynamics and contrast study,lubricating characteristics are analyzed in the presence and absence of impact impulses. The results are shown as follows. Considering of the impact impulse,the pressure of oil film of the 3rdmain journal changes from 33 MPa to 142 MPa and the minimum thickness of oil film is 0. 002 mm. The oil film is not broken. This study provides important reference when dealing with the reliability design of free fall lifeboats.