For the sound insulation materials of product equipment, such as passenger cars, high-speed trains, airplanes and other interior sound insulation materials, it is necessary to use sound insulation materials like sound insulation pads. These materials are generally composed of polymer. Due to the quality theorem of sound insulation and the lightweight requirements of these products, the density of these sound insulation pads needs to be designed according to the actual situation. In the actual design and application of sound insulation materials, first of all, it is required to design the sound insulation structure with the largest sound insulation amount and the lightest structure within the noise frequency band; at the same time, in the actual use, it is also necessary to consider the impact of field sealing and other combined structures on the overall sound insulation. The main functions of damping material, sound absorption material and sound insulation material are introduced. In the actual noise reduction project, these materials can be embodied in a single form, and also can act as a composite structure as required. For example, in order to improve the sound insulation of the structure, the sandwich composite sound insulation structure of sound insulation absorption sound insulation is widely used at present; and in the noise reduction of oil and gas pipelines or central air conditioning and other shell structures, the package structure of damping absorption sound insulation is also used.
The pipeline plays the role of the transmitter in the vibration of the equipment, and plays the role of "sound bridge" in the transmission of structural noise. Therefore, the pipeline has always been the key object of vibration reduction and noise reduction. There are two kinds of commonly used methods to control pipeline vibration: first, connect flexible pipe in series in the pipeline to isolate vibration energy transmission; second, install damping structure outside the pipe wall to absorb and dissipate vibration energy. Damping treatment is often used as an auxiliary technical measure in the pipeline, but it is found that the damping treatment has the same damping effect as the flexible connecting pipe in the relevant tests. At the same time, the pipeline damping treatment technology has its own advantages in not changing the pressure bearing strength of the pipeline and facilitating the construction, which has a very wide application prospect.
The damping material used in the pipeline system not only requires excellent damping performance of the material itself, but also requires certain flexibility to facilitate the winding and wrapping of the pipeline. However, the common damping materials are either high hardness or low damping performance, which are mainly used in the plane part or the part with small curvature. In view of this situation, putsmier precision aviation equipment developed oil resistant flame-retardant damping materials, and made damping belt, perforated vibration isolation pad and vibration isolation pipe clamp and other pipeline vibration damping products, which achieved good vibration reduction effect.
The vibration of the pipeline can be reduced by wrapping the damping tape, which can reach 5dB in some parts; the vibration transmission of the pipeline can be reduced obviously by damping the pipe clamp with the perforated vibration isolation material, and the insertion loss can reach more than 4dB. It can be seen that the vibration of oil and gas pipeline can be obviously suppressed by damping coating and pipe clamp. Therefore, putsmier damping treatment is a very simple and effective means of pipeline vibration control, which can be widely used in noise and vibration control engineering of pipeline system.
