Practical torsional analysis and coupling selection for multi-machine complex process rotating equipment trains

Abstract

A multi-machine train consists of several complex shafts, rotors, or crankshafts and relatively flexible shaft extensions and couplings. It may also include gear unit, clutch, or flywheel. As connected machines function as spring systems in series, the potential exists for torsional resonance and torsional fatigue damage. Couplings are often modified to tune the overall system. Practical torsional analysis method, useful recommendations, and optimum coupling selection are addressed. Case studies for rigid connection (flange-to-flange connection without coupling), high torsional stiffness coupling, and flexible coupling are also investigated.