Teisingas metodas matavimas - triukšmas metras
Kai matavimas the noise meter, the instrument should select the correct gear according to the situation. Hold both sides of the noise meter flat with both hands, and the microphone points to the sound source being measured. You can also use extension cables and extension rods reduce the impact of the noise meter's appearance and the human body on the measurement. . The location of the microphone should be determined to aktualūs reglamentai.
The sound level meter used by the noise machine to measure noise, the meter response can be divided into four types render to the sensitivity:
(1) "Slow". The time constant of the meter is 1000 ms, which is paprastai used to measure steady-state noise, and the measured value is the effective value.
(2) "Quick". The time constant of the meter is 125ms, which is paprastai naudojamas to matas nestabilus triukšmas ir transportas triukšmas su dideliais svyravimais. Greitos pavaros are arti į kaip žmogus ausis reaguoja į garsą.
(3) "Pulse or pulse hold". The needle rise time is 35ms, which is used to measure long-duration pulse noise, such as punches, hammers, etc. The measured value is the maximum effective value.
(4) "Peak hold". The rising time of the needle is less than 20ms. It is used to measure short-duration pulse sounds, such as guns, cannons and explosions. The measured value is the peak value. That is the maximum value. Distance meter, height meter, laser line meter, flow meter, GPS thickness meter, level meter, flat plate meter, waveform recorder, test fixture, voltage and current įrašymo įrenginys, duomenys kolektorius, grafikas įrašymo įrenginys, srautas totalizatorius instrumentas.
The sound level meter can be connected to an external filter and recorder to perform spectrum analysis on the noise. The domestic ND2 precision sound level meter is equipped with an octave frequency filter, which is easy to carry to the site and perform spectrum analysis. Process Calibrator Temperature Calibrator Pressure Calibrator Loop Calibrator Calibration Buffer Clamp Meter Calibrator Oscilloscope Calibrator Noise Meter Calibrator Current Calibrator Multifunctional Calibrator Humidity Calibrator pH Calibrator
Improve the structure of mechanical equipment and apply new materials to reduce noise. With the development of materials technology, various new materials have emerged. It has become a reality to use some high-damping alloys and high-strength plastics with large internal friction to produce machine parts. For example, high-strength plastic parts are often used in automobile production. For fans, different types of blades produce different noises. Choosing the best blade shape can reduce noise. For example, changing the fan blades from straight to backward curved, or reducing the length of the blades can reduce noise. Generally, the noise generated by gear transmission devices is relatively large, up to 90dB. If helical gears or spiral gears are used instead, the coincidence coefficient during meshing will be large, which can reduce the noise by 3 to 16dB. If belt transmission is used instead of general gear rotation, the noise can be reduced by about 15dB because the belt can play a vibration damping role. For gear transmission devices, noise can also be reduced by reducing the linear speed of the gear and selecting an appropriate transmission ratio. Tests have shown that if the linear speed of the gear is reduced by half, the noise will be reduced by about 6dB.
