Abstract
Forty-three years of favorable experience with weighed water testing of steam turbines influenced a decision to install scale tanks at Wisconsin Electric Power Company’s new Oak Creek Power Plant to permit testing the 120,000kw cross-compound reheat turbines. At a total cost of less than ten cents per kilowatt installed capacity, the weighing tanks serve the dual purpose of providing a means for testing turbines and their auxiliaries accurately and a needed facility for storage of cold condensate. Manufacturer’s guarantees of turbine heat rates can be checked more reliably and closely than with flowmeters, and with assurance of accurate reliable tests the manufacturer frequently can improve his guarantee. Once favorable guarantee commitments are made, experience shows that the manufacturer makes special efforts to provide the very best design. He also encourages operation at closer clearances to attain the better heat rates. Other advantages are the help in evaluating turbine internal condition which may or may not require overhaul, and in learning the effects of changes in clearance adjustments and in design changes. Routine tests are conducted with a minimum of preparation time and a relatively small test crew. Accurate measurement of all values of steam flow, electrical output, pressure, and temperature are required for reliable results, but the major emphasis on accuracy is placed on the input and output quantities which have the greatest effect on the result. The paper concludes that weighing tanks can well be considered a definite requirement whenever it is possible to fit them into the flow cycle.