Rising raw material costs of recent years compels the industry to improve wood sawing practices and efficiency. Excessive band vibration directly contributes to the poor cutting accuracy and surface quality, raw material waste, gullet cracking, and increased downtime of bank mills. Bending-torsional coupled transverse vibrations of a cutting blade are investigated by using a linear undamped axially moving thin beam model. An accurate, comprehensive, fast and inexpensive numerical method for efficient analyses of the natural frequencies and mode shapes of a cutting blade has been developed in the study. Cutting speed, cutting loads and possible constraints are incorporated in the analysis. Cutting loads induce coupled vibration modes, decrease the resonant frequency of the fundamental mode, and yield the divergence buckling. For a normal operation, more than 100% overestimate of the buckling load can be induced by neglecting bending moments and tangential cutting forces. Back-up rollers are recommended for stabilizing the saw blade.
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