Conax Buffalo is a manufacturerof temperaturesensors gas and steamturbines,generators for and other rotating equipment. Shownis the company's fiber optic gas turbine temperature sensor, industrial cable assembly and signalprocessor high temperature for turbine inlet measurement. he surge in orders for aeroderivative and heavy-duty industrial gas turbines over the past few yearshas meant busy times for component suppliers, including the manufacturers of sensors and other critical instrumentation. As the technology of these machines has evolved with higher temperatures, lower emissions and oftentimes frequent cycling, the necessity for precise temperature measurement has also increased. Conax Buffalo Technologies (CBT), Buffalo, New York, U.S.A., has a long record of supplying the power generation industry with temperature sensors and associated installation fittings. Starting in the 1960s with sensorsand sealing assembliessupplied as original equipment on steam turbines, present day CBT offerings include sensorproducts for steam and gas turbines, steam recovery systems,generatorsand other rotating machinery. "CBT has focused on the power generation market for many years and strives to provide value-addedsolutions specifically geared to the industry as it has evolved," explained Richard Lyon, turbine products manager for the company. "Steam turbine technology gave way to gas turbine development and a whole new rangeof temperaturesensing applications was demanded by manufacturers.Our involvement with gasturbines startedwith the aircraft enginesector and rapidly led to the development T of products for aeroderivatives and heavy-duty gas turbines as driven by long-standing major customers. "The consideration of benefits and improvements to industrial gasturbines through the use of Conax Buffalo products is necessarily specific to both the product and application," Lyon said. Following the 'dash for gas'and continued deregulation of electricity markets, gas turbine manufacturers have sought greater efficiencies and lower cost-of-ownership for end users and utilities, as well as compliance with international emission standards. "This phase of evolution created a requirement for longer life, cost reduction and increasedreliability for instrumentation components,"said Lyon. The development and implementation of Conax Buffalo's optical fiberbased sensor system for high temperature gaspath measurementcame about from these requirements, according to Lyon. The company's fiber optic temperature sensor system comprises a sensing element in a probe housing, a industrial fiber optic cable and an opto-electronic signal processor. The sensor technology is basedon thermal radiation, where an optically emissivematerial is heated by the gas stream and thus produces thermal radiation. This optical energy is transmitted down a sapphire light guide that is supported in a probe housing. A flexible optical fiber transmits the thermal radiation to a signal processor, where it is converted to a digital value corresponding to the probe tip temperature. The fiber optic sensorprobe component is installed at the first stageturbine inlet and the system is designed to measure temperature just downstream of the combustor. "We are given to understand that the ability to determine accurate temperatures at the first stageprovides a number of significant advantages as the requirements to have greater accuracy of control of temperatures at this point increases,"said Tony Henton, marketing manager- CBT Europe. "It is also believed that this measurementpoint is helpful in emission control. It is envisioned that the system will provide an input to the engine control system at some point in the near future - again to augment accuracy. "As further advantages, the optical fiber-basedsystemis immune to calibration drift, has predicablelife characteristics and is unaffectedby thermal shock and thermal cycling," Henton said. Conax Buffalo designs,engineersand manufacturessensorsin sizesstarting at 1 mm diameter with probe configurations available in more than 30 000 combinations of mounting styles suitable for applications from laboratory to heavy-duty industrial environments. "In the caseof traditional sensortechnologies, CBT supplies a significant number of sensorproduct designsmade exactly to individual gasturbine manufacturers' specifications.This long-term july-August 2002 Diesel& GasTurbineWorldwide