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METALWORKING EQUIPMENT AND TOOLS
    Cutting stability









































             When assessing the quality of manufacture and the very design of metal-cutting machines,
    much attention is paid to the ability of the machine to carry out a stable cutting process. In
    this case, stability, more often called vibration resistance, is understood as the possibility of
    obtaining surfaces of parts with permissible parameters waviness and roughness in a fairly wide
    range  of  cutting conditions. Vibration resistance  testing is carried  out either  experimentally
    or using approximate  analytical  methods  or using computer  simulation. In modeling, the
    elastic system of the machine tool and the cutting process are represented in the form of a
    system of differential equations, which is studied for stability. Wherein stability is assessed in
    accordance with the definition given by Lyapunov [1]. In a simplified form, this definition can
    be formulated as follows: stability is a property of a system in the process of motion, as late
    as desired, to return as close as desired to its initial state in the phase space. With regard to
    the cutting process, this means that the violation of the relative position of the cutter and the
    workpiece during cutting under the influence of external disturbances after some time after the
    disappearance of the disturbing influence will be eliminated. These processes are considered
    in the phase space defined by generalized coordinates and corresponding velocities. Even if
    we assume the adequacy of the mathematical model to the real cutting process, the presence
    of such stability upon closer examination is neither a necessary nor a sufficient condition for


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