Diagnosing To Abnormal Horizontal Vibration Of The Large-scale Diesel Engine: Theory And Practice

The large-scale diesel engine, which is used widely in the field of shipping, locomotive and generating set powered by internal-combustion engine, is a kind of power machine keeping a great quantity in society. The horizontal vibration often appears when diesel engine runs, when the horizontal vibration state worsens, the performance of the complete machine becomes bad if the state is light, which could cause the enormous economic losses directly or indirectly because of repairing; otherwise, the complete machine is scrapped and threaten the personal life, and causes the extremely serious consequence. Consequently the works of distinguishing and diagnosis horizontal abnormal vibration of the large-scale diesel engine for the purpose of finding out the malfunction reason and repair ing in time, which is important to keep the good technological state of diesel engine, and state of normal and safe machine operation. Because of the reasons mentioned above, the essay carries on the diagnosis horizontal abnormal vibration of the large-scale diesel engine. The main research contents are listed below: (1) Summarizing the technological current situation of the diagnosis of diesel engine's horizontal vibration, and discussing the application of virtual instrument technology and Lab Windows/CVI software; (2) Classing the reasons causing diesel engine's horizontal abnormal vibration according to the ways of pulses to diesel engine body, and confirming the main reasons of abnormal interval between piston and cylinder, axle working abnormally, ground defect; (3) Propos ing the diagnosis scheme, building the experiment platform according to horizontal abnormal vibration of the Model 16ZAV40S diesel engine. After test in local, obtaining and analyses the experiment data, concluding the diagnosis conclusion: the main reason of the diesel engine's horizontal abnormal vibration is the wear of piston skirt, which causes the abnormal interval between piston and cylinder. The result of the diesel engine dismantled and examined proves that the diagnosing conclusion is correct; (4) To convenient diagnosis, developing the diagnosis system to diesel engine's horizontal vibration based on Lab Windows/CVI software platform, which is a virtual instrument technology. Practice proves that, the efficiency of developing the application software and the system function of the diagnosis to horizontal abnormal vibration of diesel engine are greatly improved by the Lab Windows/CVI software.