Engine Lubrication System • Step I. Duty Report • Step II. Review • Review what they learnt in the last class • The purpose of using a cooling system • two different types and their main differences • Recite the new words • Step III. Reading material • Ask the students read the whole text and get the main idea • Discuss about the text
Engine Lubrication System • Step IV. Engine Lubrication System • New words: • Check the pronunciation of the new words • main usage of the words • Text: • We can reduce friction to a considerable degree by the use of lubrication oil.
Engine Lubrication System Types of friction Dry friction Boundary friction Liquid friction
Engine Lubrication System • lubrication oil: the four main function • a protective coating • absorb and carry the heat • wash off dirt • absorb shocks
Engine Lubrication System • What’s lubrication oil made from? • Two types of engine lubricating systems • splash • pressure/force feed • combination of the two types • main function (passage 8) • main units (passage 9-17)
Engine Lubrication System Splash lubrication （飞溅润滑） Pressure lubrication （压力润滑） Grease lubrication （润滑脂润滑）
Engine Lubrication System • Step V. Exercise • Ask the students translate some passages • Ask the students describe the main units of the lubrication system, and their main functions