Improved Operating Efficiency Through the Use of Stabilized Thermocouples

Abstract

The development of a “stabilized” temperature sensor has led to significant increases in turbine operating efficiency by maximizing output when compared with present sensor technology. These stabilized type K and E thermocouples are superior to existing standard non-stabilized thermocouples because they are not prone to the typical aging effects in the 400 to 600°C (752 to 1112°F) temperature range that can result in measurements errors. A complete set of 18 stabilized type K thermocouples were installed on the exhaust of several gas turbines used for power generation. These thermocouples were subjected to normal operating conditions for a period of one year. During that year, the increase in turbine output has ranged from 0.5 percent to almost 2.0 percent. This increase in output also translates into significant cost savings. In addition, the stabilized thermocouples have given the turbine maintenance technicians more confidence in the accuracy of their temperature measurements and resulted in improved troubleshooting and decision making. [S0742-4795(00)02502-3]