TPT July 2016

AR T I C L E

Advanced Machine & Engineering/AMSAW

by Willy Goellner, chairman and founder – Advanced Machine & Engineering/AMSAW Effect and prevention of vibration in carbide sawing by Willy Goellner, chairman and founder – Advanced Machine & Engineering/AMSAW

Each component has an infinite amount of natural frequencies and each natural frequency comes with a corresponding mode shape (Figure 1). If the excitation frequency (caused by the tooth hitting the material) matches one of the natural frequencies of the saw blade, the blade will vibrate with the associated vibration pattern. Only certain modes at lower frequencies have a damaging effect on sawing.

Vibration is harmful in any sawing machine, but in high production saws with hard, and brittle , carbide tipped blades, it can be absolutely catastrophic. Reducing vibration is the main focus for machine designers, because vibration dramatically reduces the effectiveness and tool life of the saw blade and will increase the overall cost- per-cut. When vibration is controlled, however, a carbide tipped saw blade is the optimum tool for high production sawing, because carbide can cut much faster than other materials such as high speed steel. Machine designers pay close attention to certain vibration frequencies, because not all vibration frequencies have a damaging effect. As part of the team that invented the first billet saw using carbide tipped circular saw blades and the founder of the AMSAW machines, my design team has learned throughout the past 50 years that success in carbide sawing comes from a solid understanding of four factors: vibration, resonance, damping and stabilisation. In this article – which is first of a three-part series – AME focuses on the damaging effect and prevention of vibration in carbide sawing.

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Figure 2 and Figure 3: Typical modes which include node circles and superimposed node diameters only appear at higher frequencies and have practically no effect on carbide sawing

Figure 1: Harmonic vibration patterns (modes) of circular plates. Higher vibration frequencies have little effect and are not a concern for machine designers

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J ULY 2016