Advances In Gas Turbine Couplings.
Abstract
Over the last 50 years industrial gas turbines have advanced significantly. Horsepower has increased 200 percent (and even higher) within the same envelope. Improvements in efficiencies and reliability (more operating time before overhauls) are being made more often. What took 15 years to change 30 years ago, now, in the last 15 years, happens in five years or less. There are constant demands for lighter weight, lower maintenance designs. Moreover, the operation engineers demand to be able to run six or eight years, and more, before an overhaul, not just three years. As advancements in the industrial gas turbine have occurred, so have advancements in the couplings that connect them to the driven equipment - a gear, compressor, pump, or generator. Most of the early industrial gas turbines that required flexible couplings pushed the state-of-the-art in gear couplings in the late 60s and early 70s. But because of high vibration at higher speeds, and unexpected and maintenance downtime of the equipment due to gear coupling technology, there started the industrial use of and rapid advancements in diaphragm and disc couplings for gas turbine use. In this tutorial is a comparison of the characteristics of the various types of gas turbine couplings: gear, diaphragm, and disc. (Rigid and quill shaft couplings are not covered.) The analysis of characteristics for these aforementioned different types of couplings will show that they do not react in the same way when they see the same torque and misalignment. Discussed will be the reliability of the various types, what kinds of safety margins are required, and what experience factors should be considered for various applications. Also discussed will, of course, be the conversion of gear couplings to disc or diaphragm types. In addition, the level of unbalance that can be achieved, the reactive forces that each type can produce on the equipment, and advances in the manufacturing, material, and design tools are covered.
Description
Tutorialpg. 157-172
Subject
TurbomachinesCollections
Citation
Corcoran, Joseph P.; Lyle, Douglas; McCormack, Patrick; Ortel, Tim (2007). Advances In Gas Turbine Couplings.. Texas A&M University. Turbomachinery Laboratories. Available electronically from https : / /hdl .handle .net /1969 .1 /163152.