The Introduction to Method and Solution of Automobile Noise Reduction

1. The thermal insulation cotton for engine cover (also called soundproof cotton for automobiles). It absorts most of the noise when the engine is running, and it also has heat insulation function, can effectively protect the original paint of the hood and avoid  long time high temperature to make the  paint fade.

2.The sound insulation material of the vehicle chassis, the shock absorber pad and the moisture-proof and soundproof cotton in the central chassis and the rear chassis in carriage. The main function is to deal with the chassis under the central chassis and the luggage compartment, for the vibration resonance of the sheet at high speed, the road noise from the tires to the chassis, and the resonance sound pressure of the exhaust sound into the rear box(better with chassis armor).

3. Special shock absorbion and sound insulation board for inside and outside door maintenance warehouse. Strengthen the steel property of door plate and and reduce the resonance of the door sheet metal due to its thinness during driving,  which may result in the loosening of door interior metal parts, or lower the noise generated by metal fatigue and twisting of the vehicle body ,because the car is old and long-term driving on rugged roads. Meanwhile,the sound-insulating cotton in the door trim panel is added to effectively absorb the wave and improve the sound quality of the speaker.

4.The engine fire wall sound insulation, and muffler pad under instrument seat . The engine is the main source of noise, and it is also the nearest noise source  to the driver. After strengthening the thickness of the underpart of dashboard and the engine firewall, it can suppress the high-frequency sound pressure that is transmitted into the interior of the vehicle when the engine speed is raised, which is the most obvious part of the sound insulation project.

5.The soundproof strip of doors, whose main function is to strengthen the sealing of the doors and door frames, can effectively reduce the wind shear sound during high-speed driving , and can also replace the old and elastic fatigue waterproof strips, the most important thing is to make the air tightness in the carriage better.

6.The sound –proof of front and rear hubs and leaf boards, this is the place where the chassis noise is mostly often introduced, which includes the noise introduced by the shock absorbers, and the noise generated by the tyres and p avement, gravel and sheet metal in driving .After improvement, the noise caused by the road surface and shock absorber can be significantly reduced . The cost of this improvement is high, but the effect obtained is also obvious.