Most mufflers adopt the principle of impedance compound muffler. Due to the complex structure, heavy weight, high temperature oxidation sound absorption packing, high speed airflow impact sound absorption packing, water gas penetration sound absorption packing and other reasons, resulting in frequent muffler maintenance, poor sound reduction effect, short service cycle and so on. Is the design difficulty of the muffler, the use of microperforation hole multi-cavity structure muffler, do not use any resistive sound absorption filler, high pressure airflow in the muffler through multiple flow control into the cavity, damping separation expansion and depressurizing, step by step to change the original airflow of sound frequency. The resistance loss is small, the muffling frequency band is wide, can not afford dust when working. Not afraid of oil mist, water vapor. Resistant to high temperature and high speed airflow. Comprehensive muffling effect, the use of the most reasonable cycle of muffling principle design.