Analysis and Application of the National Standard for Noise of Roots Blowers
Regarding the national standards for Roots blower noise, the following aspects can be referred to:
1、 Measurement standards and methods
According to the national standard GB/T 2888-2008 "Measurement Method for Noise of Fans and Roots Blowers", noise level measurement shall be carried out. This standard specifies the noise measurement methods for A-level and sound pressure level, as well as the noise measurement methods for sound power level. Suitable for noise measurement of general types of ventilation fans, turbine blowers, turbine compressors (hereinafter referred to as fans), and Roots blowers.
2、 Measurement conditions and requirements
1. Measurement environment: The measurement environment should comply with the provisions of GB/T 2888-2008, and should try to avoid reflected sound from objects outside the ground, and meet the conditions, such as facing the center of the air inlet from the center line of the air inlet, and facing the center of the air outlet at a 45 ° angle to the center line of the air outlet.
2. Environmental noise: The reading of environmental noise is 10dB (A) lower than the noise of the measured object. If the difference between the environmental noise and the measured fan noise level is less than 3dB (A), noise measurement cannot be performed.
3. Operating conditions: Noise measurement should generally be carried out under rated speed and flow conditions. If agreed upon with the user, measurements can also be taken under other conditions, but specific operating conditions should be clearly recorded.
4. Measuring instruments: Use sound level meters and octave band filters or equivalent measuring instruments. Sound level meters and octave band filters should comply with relevant standards and regulations.
5. Measurement device: The measurement device for fans and Roots blowers should comply with the corresponding performance test method standards. During installation, the noise generated by the vibration of the tested fan and Roots blower, as well as the reflected sound from the ground and other objects, should be reduced.
6. Measurement procedure: When measuring the noise of fans and Roots blowers, it is generally carried out simultaneously with the aerodynamic performance test. The noise measurement value at each operating point should be measured simultaneously with the corresponding aerodynamic performance measurement value.
7. Measurement point location: Determine the measurement point location based on the type and configuration of the fan, usually at the center height of the inlet, outlet, or casing.
3、 Relevant clauses in the national standard for Roots blowers
The national standard for Roots blowers does not have clear regulations on the noise level of Roots blowers, but it is stipulated that appropriate noise reduction and insulation devices should be selected according to the requirements of the operating environment for noise.
In summary, the national standards for noise of Roots blowers mainly involve measurement standards and methods, measurement conditions and requirements, as well as relevant clauses in the national standards for Roots blowers. In practical use, appropriate silencing and sound insulation devices should be selected according to the specific usage environment and requirements to reduce the noise level of Roots blowers.
