| Brazing diamond saw blade has several advantages such as high grits, strong retention, strength and reliable matrix, operating safety, high processing efficiency etc. The practice showed that the traditional monolayer and multilayer electroplating sintering was consolidated with grits and coating in resin cutt or fetus through mechanical actions. The results showed that defects of grits’ low intensity and limited chip space, occurred on grits falling off when in process of heavy load high speed machining and matrix cracking of resin grinding wheel, limits the processing efficiency and operating safety. Compared with other types of saw blade, the brazing diamond saw blade has more furious interaction with work piece is in using process than others, which may cause sensory noise amplification and sharping. Studying regarding reducing the noise of circular saw blade has long been noticed and researched. However, the research concerning of the low-noise brazing diamond saw blade has not been widely studied presently. Therefore, this paper do a further research of the processing noise problem, and try to find out the key factors which may impact the noise of the brazing diamond saw blade and feasible noise reduction solutions.In this paper, the main works are as follows:1)By idealizing the mechanical model of cutting process, the paper analyze the time-frequency characteristic of cutting force when under different working condition. And draw the conclusion that the energy of the exciting force on saw blade is comprised by a primary low frequency component below 1kHz; High-frequency band force is widely spread. Frequency spectrum peak appears at the n times rotational frequency of the saw blade.2)By using the FEA/BEM simulation software, the principle of the noise radiation theory of brazing diamond saw blade which has common non-optimized basement is analyzed. It comes to a conclusion that the 14 inch saw blade with a thickness of 2.2mm has an extremely high radiation critical frequency upon 4.5kHz. And under the critical frequency, the impact of radiation efficiency is high to the total sound power. At the frequency of about 1kHz and 2kHz, which the circle node mode shape just occurs, the radiation efficiency is just at the peak value of low frequency band. The situation is same at the high frequency band.3)Two logarithmic parameters named “vibration reduction level” and “noise radiation efficiency reduction level” have been put forward, which can replace the absolute parameters, analysis the acoustics reduction capacity with a more intuitive way. Also it avoid the uncertain boundary conditions of exciting force in simulation model. By this way, the noise reduce ability of saw blade with holes and slots is analyzed. It discovered that saw blades with strait slots at the outer side of the basement produce high vibration around the frequency of 6kHz. The M and S shape slot can reduce the noise around this frequency band. And the slots along the radial direction can form a-5dB reduction of the noise radiation efficiency. The multi-hole style noise-reduce saw blade have little effect on the reduction of total vibration and noise radiation efficiency, but still useful at special frequency band.4)Several problems which is difficult to study in simulation environment are analyzed in the experiment, including the impact to sound pressure and sound quality by damping, clamp disk, complex butterfly-slots. Also, some analysis executed in the simulation are verified, prove that the noise radiation efficiency has extremely high impact to noise power level at low and high frequency band. The sandwich-damping material and big clamp disk can reduce the noise at all frequency band. The butterfly-slot is effective at high frequency band, which conforms well to the simulation. |
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