Developments in geothermal energy in Mexico—Part twenty-two. Causes of erosion of the rotor blades in a geothermal turbine

Abstract The principal causes of erosion which affected the blades of the two last stages of a 37.5 MW e geothermal turbine are analyzed. The steam piping system, auxiliary equipment (flashers, dehumidifiers, etc.) and the turbine itself were carefully inspected. The design of the turbine and lay out of the piping system have been analyzed and evaluated. The moving blades were tested for cracks using the magnetic particle method. Also, the natural frequencies of the blades have been measured. It was concluded that the blades of the two last stages should be replaced and the steam path of the low pressure part of the turbine must be modified to avoid similar problems in the future. Several simple modifications of the piping system were recommended as well.