(194b) Torque Measurement Devices on Large Tubomachinery

The use of continuous torque monitoring couplings is quickly becoming an integral part of many predictive maintenance programs in the petrochemical and process industries. More and more operating facilities are using instrumented torque-measuring couplings in order to know how their critical equipment is performing so that the intervals between scheduled shutdowns can be chosen appropriately. This paper will cover a brief history of torque meters; i.e., the basic measuring types which are 1) strain gage types and 2)torsional deflection types. Discussed will be the theories of operation on how they work. Also discussed will be the advances and limitation of these types. Included will be the accuracies that can be obtained by each one and the features and limitation of each. In addition, covered will be a new advance in the mechanical torsional deflection, or phase shift type, which improves the overall design so that mass elastic properties of the coupling with the torque meter are more compatible with high-speed turbomachinery.