Page 334 - Subyek Teknik Mesin - Forsthoffers Best Practice Handbook for Rotating Machinery by William E Forsthoffer
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Be st Practice 5 .13          Steam Turbine Best Practices


           Steam turbines are not usually shop performance tested
           They are only tested mechanically (vibration, bearing
           temperatures, etc.) at no load
          Because:
           Performance (steam rate, efficiency) varies directly with steam
           velocity
           Steam velocity varies directly with steam flow
           Steam flow varies directly with power requirement because:
             Power = ΔH (energy per unit mass)  mass flow rate
           Testing at full load is not cost effective

       Fig 5.13.9   Steam turbine performance testing








           Non-extraction turbines present performance on a Willans-line
           A Willans-line describes the amount of steam flow (throttle
           flow) required for a given load at a given speed
           An extraction map describes throttle flow for a given load and
           extraction flow
           Note: all curves are for a specific set of steam conditions

       Fig 5.13.10   Steam turbine performance curves
                                                            Fig 5.13.12   Performance curve for a typical extraction steam
                                                            turbine (Courtesy of IMO Industries)





































       Fig 5.13.11   Typical performance curve for a single stage turbine with manual hand valves (Courtesy of IMO Industries)







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