Study On Wheel Loaders Noise Reduction Technology

The noise problem of the wheel loader got the attention of the society, all nations issued mandatory regulations to limit the noise of Wheel Loaders, and China also issued a new regulation for WLs. Loader manufacturers start to reduce the noise, and to increase the competitive products in the market. The thesis uses one main wheel loader model assist study subject, the main purpose is ensure the wheel loader’s sound level can meet the newest sound regulations.First of all, basing on reading a large number of related papers at homeland and abroad, this thesis systematically summarizes the current research status of loader noise, studies the test and data analysis method of the loaders’ noise control, gives the identification method for main sound source, like engine, hydraulic pump and transmission gear etc. and noise reduction method. The test method mainly according to GB standard, and analysis method mainly uses spectrum analysis.Then, it introduces the noise testing method of a wheel loader according GB standard. A large number of noise testing were performed, a lot of data were acquired, do the spectrum analysis for test data, found the main sound source according to analysis results. Apply noise reduction to the main sound source, and do the test to verify the noise reduction results.Finally, Wheel Loader’s sound level and machine spectrum analysis results is provided after noise was reduced, compared with previous data, the machine exterior sound level reduced from 116.8dB(A) to 111.5dB(A),|lowered 5.3dB(A); the ear sound level reduced from 92.8dB(A) to 84.8dB(A), lowered 8.0dB(A), the result can meet the sound regulation limit by the year 2015. Use the method of shielding to do the source ranking test, it gives the percentage contribution of the current main source, provides a basis for further noise reduction.