The Vibration Behavior of Flexibly Fixed Rotating Machines

Abstract

Needless to say, various rotational machines support today's industry. It follows that maintenance of these machines is very important to ensure their performance. ISO 10816 series (Mechanical vibration - Evaluation of machine vibration by measurements on non-rotating parts -) is widely applied to various rotational machines (motors, pumps, etc.). In this standard, we judge velocity amplitude of machine vibrations corresponding to the size of the machine while the machine is fixed on the ground and driven. However, if the operational situation prevents rigid fixation of a machine to the ground, the machine is fixed flexibly. As a result, the machine vibration is of higher amplitude than that of a machine that is rigidly fixed, and application of the existing evaluation standard becomes difficult. Therefore, the evaluation standard is relaxed for some machines. The purpose of this study is a proposal of new precise evaluation method which is considered for stiffness and damping of a flexible support base that contains springs or rubber sheets. In this paper we prepare an experimental system of one disk rotor that is supported by ball bearings at both ends, and compare vibration with a flexible support base and that with a rigid support base, by simulation and experiment.