The broadband muffler adopts the resistive-expansion chamber combination type to control the 10Hz～2000Hz high-intensive broadband noise and the infrasonic sound. The soundproof-type muffler adopts the resistive-expansion chamber combination type to control the 31.5Hz~2000Hz broadband noise. The resistive part of both mufflers adopts the nonflammable and heat-resistant sound absorption material, which is designed to be set on the top of the muffler and the channel wall for eliminating the medium and high frequency noise of the motor. The industrial-level muffler using the resistance structure is composed of the expansion chambers with the different noise-damping frequencies in series so as to control the frequency noise between 63Hz～500Hz. Both mufflers use the thick steel sheet as the exterior surface to prevent noise from diffusing.
The broadband muffler and the denoise-type muffler are of the vertical structure; their bottom plates are connected with the foundation bolts; their exhaust pipes are flange-connected with the exhaust pipes of the power cylinder equipped with the ripple compensators.
The industrial-level muffler is classified as the vertical and the suspension structures, of which the vertical is described as above. For the suspension structure, it is suspended by two brackets that are fixed onto the base, and the base is connected with the foundation through the foundation bolts.