ASME PTC 6:1996 pdf download Performance Test Code 6 on Steam Turbines
1.2 SCOPE
This Code may be used for testing of steamturbines operating either with a significant amountof superheat in the initial steam (typically fossil-fueled units) or predominantly within the moistureregion (typicaiiy nuciear-fueled units).This Code contains rules and procedures for theconduct and reporting of steam turbine testing, inciuding inandatory requirements for pretest arrangements, instrurnents to be employed, their applicationand methods of measurement, testing techniques,and methods of calculation of test resuits, The per-formancc parameters which may be determined froma Code test include:
(a) heat rate
(b) generator output(c) steam flow
(d) steam rate(e) feedwater flowit also contains procedures and tcchniques required to determine enthalpy values within the mois-ture region and modifications necessary to permittesting within the restrictions of radiologica! safctyrequirements in nuclear plants.
1.3 FULL-SCALE AND ALTERNATIVE TESTS
Iwo steam turbine testing procedures are pre-sented. For either procedure, primary flow may be measured either in the condensate linc or in thefeedwater line downstream of the final feedwaterheater. The parties may agree to variations betwcenthe full-scale and alternative tests as long as thephilosophy of minimum uncertainty is followed indeiail.
1.3.1 Full-scale test, The full-scale test requiresextensive thermmal cycle measurements and calcula.tions which provide detaiied information about theturbine HPIP, and LP individual component per-formance. A full-scale test will produce results witha minimum uncertainty.
1.3.2 The full-scale test with condensate iluw mea
surement is recommended for conducting acceptance tests of fossil unit steam turbines. Withuutprior written agreement bctween the parties to anacceptance test, this procedure shall be used.
1.3.3 Alternative test. The alternativc test relieson fewer measurements and makes greater use ofcorrection curves for cycle adiustments and heatetperformance with resultant cost savings over the ful!scale test. The test uncertainty is slightly increasedcompared with the full-scale test. For a nuclear unit,the aiternative test with feedwater flow measurementmay be preferred depending on the furbine cycledesign. Use of this procedure requires agreementbetween the parties io an acceptance test.
1.3.4 The data from the alternative test proceduremay produce a slightly higher uncertainty in resultsparticularly if there is substantiai divergence betweenthe test and the specified cycle. The parlies to thetest must agree on a course of action if the turbinefails to meet specificd pcrformance. The alternalivetest may not provide the information necessary todetermine individual component performance compared to expected because only thosc measurementsneeded to calculate test heat rate and to permitcomparison to specific conditions are required. It isrecommended that al provisions and source connections for a full-scale test be included in the designof the cycle, should such a test be required at a latertime and to facilitate individual frbine componentperiornance testing.