Roots blower It is a commonly used air supply equipment in factory production, but the noise pollution of Roots blower is also very serious, which has caused great harm to the environment and human body. Today, let's learn how to reduce the noise of Roots blower.
1、 Formation of noise of roots blower
The noise of Roots blower mainly comes from mechanical noise, electromagnetic noise and airflow noise. Mechanical noise is caused by the operation of gears and bearings inside the machine, the vibration of the machine body, plus friction and impact. The air flow noise is caused by the rotating blades of Roots blower squeezing the air and driving the air flow to form a turbine. Among these factors, the intensity of airflow noise is high, which is harmful to human body.
2、 Principle and Method of Noise Reduction for Roots Blower
Understanding the source of noise through the actual use of roots blower and spectrum analysis can not only make the investigation and measurement of roots blower noise more purposeful, but also provide scientific basis for the control and governance of roots blower noise. Through the practice in noise reduction of roots blower in recent years, the following methods can effectively control the noise pollution of roots blower:
1、 Select a reasonable type of Roots blower.
Because if the wind pressure and air volume of Roots blower in the same series are large, the noise will inevitably increase. In addition, the excessive margin of Roots blower not only consumes electric energy, but also has to be matched with the corresponding pipe network and operation system to reduce noise. For the roots blower of the same model, if the performance allows, the roots blower with low speed should be selected as far as possible. When the roots blower reaches a certain flow, the speed should be reduced to reduce the noise.
2、 Foundation damping
The Roots blower will produce strong vibration and mechanical noise during operation, and the shock wave will be transmitted to other components through the body of the Roots blower, and people will feel a strong vibration from the ground near the Roots blower. In order to reduce the mechanical vibration, the precision of the equipment should be improved to improve the operating condition of Roots blower, so as to reduce the coupling between Roots blower and other transmission media. To reduce the vibration transmitted by the fuselage through the ground, separate equipment foundation can be set to isolate the fuselage from the ground of the machine room, such as setting damping ditches or grooves around the foundation. Alternatively, some elastic materials, such as spring shock absorber, can also be used as the isolation device of the engine base. This method has been adopted in many projects with good results.
3、 Construction measures
Building measures can also be taken to reduce the noise of roots blower. This method is not only simple in design, but also convenient in construction. Common construction measures include: setting an independent machine room for Roots blower; A duty room with good sound insulation shall be established in the machine room for the duty personnel to contact and rest. The duty room shall avoid facing the doors and windows towards the machine room; The suction outlet should be set at a position that has no impact on the environment, and the air inlet should be set underground as far as possible, with a thick cover plate set above it; The air vent is very noisy and causes serious environmental pollution, so an anechoic pit or exhaust anechoic chamber can be built. The air outlet can also be placed in the pit or ditch outside the machine room according to the actual environment.
4、 Setting the silencer
Installing silencers on the intake and exhaust pipes of Roots blower is an effective measure in noise control of Roots blower, which can effectively reduce the air flow noise. There are certain principles in the type and selection of silencers. The common silencers matching the intake and exhaust pipes of Roots blower are: resistive silencers suitable for medium and high frequency, reactive silencers suitable for medium and low frequency, micro perforated plate silencers suitable for low and medium frequency broadband silencing, and combined special silencers.
5、 Set enclosure
Enclosure is set around the unit, which can effectively prevent the noise of Roots blower from being transmitted to the outside, so as to limit the noise within a certain range. This method is simple and easy both in building new plants and in noise control. The enclosure structure of the unit usually uses heavy materials, such as 240 thick brick walls, 200 thick aerated concrete blocks, etc., and direct vents or other sound transmission ports should be avoided as far as possible to improve the enclosure structure's closeness and sound insulation capacity. Of course, totally enclosed Roots blower sound insulation room can also be used, and 60mm thick microcellular foam plastic can be added to the inner wall of the sound insulation room; Felt shall be filled in the wall gap and air duct position to absorb noise. In addition, in order to minimize the damage to human body caused by the noise of Roots blower, a duty room with sound insulation function should also be set up. The duty room should be equipped with a remote electromechanical integrated intelligent automatic control system that can display the working conditions such as temperature, wind pressure, and motor current in real time, as well as start, stop, fault alarm and other functions, So as to realize man-machine separation.
6、 The noise of Roots blower in the pipeline system will be transmitted through the air duct through reasonable treatment. Therefore, reasonable treatment of the pipeline system is also one of the methods for noise control of Roots blower. There are mainly the following methods for handling air ducts:
1. If conditions permit, the inner wall of the air duct can be properly thickened to increase the rigidity of the duct and reduce the regenerative noise caused by vibration, such as installing 4-6 mm steel plates.
2. The bend or joint of air duct shall be treated flexibly, which can reduce the noise caused by air flow impact. Elastic cushion and flexible pipe section shall be installed at the place where the pipe passes through the wall and contacts with the support. The support shall have sufficient rigidity, and the contact between the support and the ground shall be subject to shock absorption. It has good effect on shock absorption and noise reduction. The pipe support shall have sufficient rigidity, and the contact between the support and the ground shall be properly damped.
3. If conditions permit, reduce the wind speed and increase the pipe diameter. This not only helps to reduce the air flow noise, but also enables the muffler to play a better role in practice.
4. Add damping materials on the outer wall of the air duct. When the high-speed airflow passes through the pipe wall, it will hit the pipe wall to form high-frequency vibration. Adding damping materials on the outer wall can effectively reduce the vibration frequency. For example, wrapping straw rope on the outer wall of the pipeline, or directly installing a wooden cover on the outer wall of the pipeline, and filling sawdust in the wooden cover, all have good effects. Damping materials shall be anti-corrosion and fireproof inorganic materials as far as possible, such as mineral wool, perlite, etc.
The above is the way to reduce the noise of Roots blower. I believe you will understand how to reduce the noise of Roots blower after reading it. I hope it will help you.
