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Automobile Engine Lubricating System and Maintenance
学院: 诚毅学院
学期:2014-2015第一学期
课程: 专业英语(一)
专业: 车辆工程
班级: 车辆1291
学号: 201241043007
姓名:
Automobile Engine Lubricating System and Maintenance
Lubrication system:
Engine, transmission parts are many small gap testimony phase Liu speed movement, such as the crankshaft main journal and main bearings, crank pin and connecting rod bearings, camshaft journals and cam bearings, pistons, piston rings and cylinder wall, gas distribution and transmission deputy sports bodies and other gear pair. Although the working surface of these parts have been fine processing, but magnified view of these surfaces is uneven. Engine movement and the relative movement of the parts in the work, the work surface in a high speed moving state, and some parts are still under a large load of work ( such as crankshaft or camshaft bearings, pistons and cylinder wall, and the duct valve, hold or rocker cam, etc.) Therefore, the work surface must be lubricated. Whatever parts surface machining accuracy high, must be in two parts of the friction surface is maintained between a layer of oil film, in order to reduce the wear and tear parts and power consumption .If not for the lubrication can cause dry friction. Dry friction resistance is very big, not only causing the increase of engine power consumption, still can make parts wear speed, shorten service life. More seriously, when due to dry friction heat is very big, can make the parts temperature rise rapidly in a short time, destroy the fit clearance, make exercise a movement, a further rise in temperature in surface melting and gelling, cause serious engine mechanical accident even scrapped.
Composition lubrication system:
Main oil cylinder head, piston pins, connecting rods oil channel, crankshaft oil passages, oil pump, crank pin journal crankshaft main journal, etc.
The main functions of the lubrication system:
1. Lubrication: can make the engine internal motions between the sur