... 6Heavy-Duty Gas Turbine Operating and Maintenance ConsiderationsFigure 7. GE bases gas turbine maintenance requirements on independent counts of starts and hoursFigure 8. Hot -gas- path maintenance ... steam turbine rotor size increases of the1950s and 1960s, gas turbine rotors have seen agrowth trend in the 1980s and 1990s as the tech-nology has advanced to meet the demand forcombined ... of gas turbine aux-iliary components such as fuel pumps and flowdividers.As shown in Figure 11, gas fuels, which meet GEspecifications, are considered the optimum fuelwith regard to turbine...