Discussion on characteristics of ventilator sound removal equipment and analysis of accessory placement
Reasonably choose the cutoff frequency of the muffler. The upper and lower cutoff frequencies of the general muffler are selected as 4000 Hz and 250 Hz, respectively; between the upper and lower cutoff frequencies, the muffler should have sufficient muffling value for each frequency. A certain degree of silencing effect can also be obtained in a small range other than the cutoff frequency, so eight test center frequencies (Hz), that is, 63, 125, 250, 500, 1000, 2000, 4000, 8000 are generally set. The reasonable airflow speed of the selected muffler. The allowed airflow speed is selected based on the set 8 center frequencies, the allowable drag loss, and the noise level actually presented after the muffler is installed. For the ventilators used in industrial production, the airflow speed of the muffler is generally selected to be 1525 m/s; for the ventilation of construction engineering or air conditioning, the airflow speed of the muffler can be selected to be 515 m/s. The experiment analyzes and selects the type and specification of the muffler. Due to the different conditions of the ventilation system, the muffler must be analyzed and selected according to the actual noise level of the fan and the actual muffling value of the muffler. For small and medium sized fans, high pressure fans and blowers, a circular muffler is generally selected; for large fans and ordinary blowers, a rectangular muffler can be selected. Only when installed in a suitable part of the noise source of the fan can a better noise reduction effect be obtained. The noise of the ventilator combination system comes from three parts: fan, motor and pipeline. The main noise component is the noise radiated by the aerodynamic noise through the housing of the equipment. Therefore, installing the muffler in the inlet and outlet of the pipe is the preferred solution.
If the air inlet and exhaust are far away from the fan and the motor, the muffler should be installed indoors and the noise reduction value can reach 1520dB. There may or may not be connected between the air inlet or the exhaust port and the muffler. However, if a soft joint is used between the intake and exhaust ports and the muffler, the effect is better; the soft joint is generally a high-strength rubber hose of a suitable size. Reliable gaskets should be installed at all flange joints to prevent leakage and air leaks. In order to alleviate the radiation noise of the pipe wall and improve the noise elimination effect, the surface of the pipe should be coated with asphalt and affixed with a layer of felt paper, covered with asbestos, bundled with wire mesh, and finally coated with lime slurry. It is important to note that when the ventilation duct contains more water and sand, it is not advisable to use a resistive muffler. Moreover, the muffler should be regularly inspected and tested like other equipment to ensure its noise cancellation. At present, China's annual production capacity of ferroalloys exceeds 5 million tons, ranking first in the world.
Hook strip flat screen.
Steel frame screen.
Composite frame screen.
Hook strip soft screen.
Shale Shaker Screen,Api Shale Shaker Screen,Vibrating Shale Shaker Screen,Api Plate Shale Shaker Screen
Henan Youlong Petroleum Engineering Technology Co.,Ltd , https://www.youlongenergy.com