Analysis Of Powertrain Bearing Wear And Gear Noise

As the power source of automobile, automotive powertrain consisting of contains engine and transmission mainly. In the process of new cars'research and development, engine and transmission are the important parts of it. When the the company, which the author works in, develops a car as self owned brand one, and in this process, two problems are exposed that the bearing pad wears seriously in in durability test and the transmission generating loud noise when the engine speed up and speed down in car matching for the new car's powertrain. In this paper, the main causes and the solutions of the two problems above mentions are found and given. The paper not only resolves the powertrain problems, but also works out a relative analysis method for related issures of powertrain.Aiming at the wears seriously problem of bearing pad of powertrain, several steps are carried out. First, by analysing the components'assembling effect, dimensions, material chemical composition and the form of worn out surface are, the wear type of the bearing pad that is adhesive wear, are obtained. Secondly, the possible causes of adhesive wear, including the material of rubbing pair, load, surface temperature, lubrication condition and so on, are checked and analyzed. Then, the primary cause of bearing pad'abnormal wear is found that is unsuitable process leading to the leak of lubricating oil for bearing pad and poor lubrication. Finally, by improving processing technic and cutter to decrease the leak of lubricating oil for bearing pad, the bearing pad wearing problem is solved. Aiming at the fault problem of transmission generating loud noise when revolving speed changes, the noisy signals and the data of revolving speed'fluctuation collected from the transmission are analyzed, and the cause of loud noise of transmission is found that is improper rigidity and damping for clutch. The noise of transmission is decreased obviously by adjusting the rigidity and damping for clutch.The content of this paper is a typical automobile power fault analysis, the modifications of components'dimensions and processing technic is guided by means of theoretical analysis and test. The paper not only solves the fault problems in the process of the development of new car's powertrain, but also obtains a relatively distinct analysis idea, which provides a reference for new car'development and engineering application.