TWENTY-THREE YEARS OPERATING EXPERIENCE WITH THE WORLD'S LARGEST BOILER FEEDWATER PUMP

摘要

On the American Electric Power system, increases in generating unit size progressed from a 225 megawatt (MW) unit to the 1300 MW units, which remain the largest supercritical coal fired electric generating units in the world. Each of these units is equipped with a single boiler feedpump. The utility's experience has proven that the single, turbine-driven feedwater pump concept is extremely reliable and durable under base load conditions. Operating at these conditions, the changeout interval for pumps on the 1300 MW units was as long as five years. Since the 1980s, these units have been operating in the load cycling mode, reducing this changeout interval to as short as one year. Discussed herein are the utility's operational experience and the evolution of pump component design to accommodate the attendant increase in running time at reduced capacities. Changes were made in the hydraulic and mechanical design of the pump, and in overhaul and maintenance procedures. With these improvements, the original changeout interval has been restored for both base load and cycling operation. Continued developments in the area of high energy pump technology promise even greater durability in the future.