1、STD-BSI BS EN b0753-2-ENGL 199b m LbZqbbS Ob7934L 2T3 BRITISH STANDARD Rules for steam turbine thermal acceptance tests Part 2. Method B : Wide range of accuracy for various types and sizes of turbines The European Standard EN 60953-2 : 1995 has the status of a British Standard ICs 27.040 BS EN 5095
2、3-2 : 1996 EC 953-2 : 1990 NO COPYING WITHOUT BSI PERMISSION EXCEPT AS PERMITTED BY COPYRIGHT LAW STD-BSI BS EN b0753-2-ENGL L99b Lb2qbbS Ob793Y2 L3T I hid. No. I Date BS EN 60963-2 : 1996 Issue 2, February 1998 Text affected Committees responsible for this British Standard The preparaton of this Br
3、itish Standard was entrusted to Technical Committee MCWl3, Steam turbines, upon which the foowing bodies were represented: Association of Consuiting Engineem Electricity supply Industry in England and Wales North of Scotland Hyru-electric Board Power Generation Assauab . on(BEAMAUa) South of Scotlan
4、d Electricity Board 9860 The foiiowing BSI references relate to the work on this standard: Committee reference MCW13 DraRannouncedin BSZ Naus ISBN O 580 25631 6 STD-BSI BCEN bU9.53-2-ENGL 199b = Lb24bb7-0b77343 07b Issue 1, February i998 BS EN 60953-2 : 1996 Page Front cover Inside front cover a b i
5、 ll EN title page Summary of pages The following table identifies the current issue of each page. Issue 1 indicates that a page has been introduced for the first time by amendment. Subsequent issue numbers indicate an updated page. Vertical sidelining on replacement pages indicates the most recent c
6、hanges (amendment, addition, deletion). Issue Page 2 2 to 26 2 27 1 28 blank 29 original 30 to 118 2 Inside back cover original Back cover Issue original 2 original 2 original original original O BSI 1998 a STD.BS1 BS EN b753-2-ENGL 197b lbZ4bb7 Ob79344 TO2 m BS EN 60963-2 : 1996 Contents page Commi
7、aees responsible Inside front cover Nationa foreword ii Foreword 2 Text of EN 60953-2 3 i BS EN 60953-2 : 1996 Issue 2, Febniary 1998 National foreword This British Standard has been prepared by Technical Committee MCW13 and is the English ianguagedon of EN 60963-2: 1995Ruk.s forsteam tuMm themzal c
8、mwptunce tests Part 2: Methal B Wide mnge of accumcy for vaW t- and furthermore, procedures are recommended for treating cases where these specifications cannot be met. When good-standardized instrumentation and procedures are applied in a test, the measuring uncertainty of the result will usually a
9、mount to 0.9% to 1.2% for a large fossil fuel fired condensing unit, to 1.1% to 1.4% for a nuclear unit and to 1.5% to 2.5% for back pressure, extraction and small condensing turbines. It is possible to reduce these values by additional improvement in instrumen- tation, primarily by additional measu
10、rements of primary mass flows and/or calibration of measuring devices for primary mass flow. 2) Main differences between Methods A and B In Method A, much more detailed information concerning the preparation and conduct of the tests and the measuring techniques are contained for guidance of the part
11、ies to the test than in Method B. In Method B, the detailed treatment of the objectives is left somewhat more to the discretion and decisions of the participants and necessitates sufficient experience and expertise on their part. 3) Guiding principles The requirements concerning the preparation and
12、conditions of the test and especially such conditions of the test as duration, deviations and constancy of test conditions and acceptable differences between double measurements are more stringent in Method A. The test should be conducted preferably within eight weeks after the beginning of the oper
13、ation. It is the intent during this period to minimize performance deterioration and risk of damage to the turbine. Preliminary tests including enthalpy drop tests should be made during this period to monitor HP and IP turbine section performance. However, these tests do not provide LP section perfo
14、rmance and for this reason it is imperative to conduct the acceptance tests as soon as practicable. Whatever the case, when using Method A, if an enthalpy drop test indicates a possible deterioration of the HP or IP section, or if the plant conditions require that the tests be postponed more than fo
15、ur months after the initial start, then the acceptance tests should be delayed. An adjustment of the heat rate test results to start-up enthalpy drop efficiencies or for the effects of aging is not permitted when using Method A. If the test has to be postponed, Method A proposes that the test be car
16、ried out after the first major internal inspection; several methods are proposed for establishing the approximate condition of the turbine prior to the tests. 4) Instruments und methods of measurement a) Measurement of electrical power In addition to the conditions required for the measurement of el
17、ectric power, which are similar in both methods, Method A requires a check of the instruments by a comparison measurement after each test run; the permissible difference between double measurements is limited to 0.15%. For the measurement of main flows the use of calibrated pressure difference devic
18、es is required in Method A. The application of a device not covered by international standardization, the throat- tap nozzle, is recommended therein and details of design and application are given. b) Flow measurement The Calibration of these devices shall be conducted with the upstream and downstre
19、am piping and flow-straightener. Methods for the necessary extrapolation of the discharge coefficient from the calibration values are given. STD-BSI BS EN b0953-ENGL L97b lb24bb7b79350 20b i Page 6 EN 60953-2 1995 In Method B standardized pressure-difference devices are normally applied for flow mea
20、sure- ment. Calibration is recommended where a reduction of overall measuring uncertainty is desirable. Double or multiple measurement of primary flow is recommended for the reduction of measuring uncertainty and a method for checking the compatibility is described. c) Pressure measurement The requi
21、rements and recommendations for pressure measurements are essentially similar. Only the methods for the measurement of exhaust-pressure of condensing turbines differ to some extent. d) Temperature measurement The requirements are essentially similar in both methods. However detail requirements are m
22、ore stringent in Method A: - calibration before and after the test, - double measurement of the main temperature with with 0.5 K maximum difference, - thermocouples with continuous leads, - required overall accuracy. e) Steam quality measurements Methods A and B are identical. 5) Evaluation of tests
23、 The preparatory work for the evaluation and calculation of the test results is covered in a very similar manner in Methods A and B. However, quantitative requirements are more stringent in Method A. Method B contains some proposals for handling cases where some requirements have not been met to avo
24、id rejection of the test. In addition, Method B contains detailed methods for calculation of measuring uncertainty values of measured variables and tests results. Method B recommends other methods for conducting and evaluating of the tests after the specified period and without a previous inspection
25、. 6) Correction of test results and comparison with guarantees The correction of test results to guarantee conditions is covered in both Methods A and B. Method A provides for the comparison of test results to guarantee without consideration of Method B gives a broader spectrum of correction procedu
26、res. Furthermore, the measuring measuring uncertainty. uncertainty of the result is taken into account in the guarantee comparison. 7) Proposals for application Since the acceptance test method to be applied has to be considered in the details of the plant design, it should be stated as early as pos
27、sible, preferably in the turbine contract, which method will be used. Method B can be applied tosteam turbinesof any type and any power. The desired measuring uncer- tainty should be decided upon sufficiently early, so that the necessary provisionscan be included in the plant. If the guarantee inclu
28、des the complete power plant or large parts thereof, the relevant parts of either method can be applied for an acceptance test in accordance with the definition of the guarantee value. - - STD-BSI BS EN b0953-2-ENGL 199b-k lb24bb7 Ob79351 142 Page 6 EN 60963-2 : 1996 1. Scope and object 1.1 1.2 1.3
29、2. 2.1 Scope The rules given in this standard are applicable to thermal acceptance tests covering a wide range of accuracy on steam turbines of every type, rating and application. Only the relevant portion of these rules will apply to any individual case. The rules provide for the testing of turbine
30、s, whether operating with either superheated or saturated steam. They include measurements and procedures required to determine specific enthalpy within the moisture region and describe precautions necessary to permit testing while respecting radiological safety rules in nuclear plants. Uniform rule
31、s for the preparation, carrying out, evaluation, comparison with guarantee and calculation of measuring uncertainty of acceptance tests are defined in this standard. Details of the conditions under which the acceptance test shall take place are included. Should any complex or special case arise whic
32、h is not covered by these rules, appropriate agreement shall be reached by manufacturer and purchaser before the contract is signed. Object this standard is to verify guarantees given by the manufacturer of the plant concerning: The purpose of the thermal acceptance tests of steam turbines and turbi
33、ne plants described in a) turbine plant thermal efficiency or heat rate; 6) turbine thermodynamic efficiency or steam rate or power output at specified steam flow conditions; c) main steam flow capacity and/or maximum power output. The guarantees with their provisions shall be formulated completely
34、and without contradic- tions (see 2.4). The acceptance tests may also include such measurements as are necessary for corrections according to the conditions of the guarantee and checking of the results. Matters to be considered in the contract with in the following sub-clauses: Some matters in these
35、 rules have to be considered at an early stage. Such matters are dealt Sub-clause 1.1 (paragraph 4) 1.2 (paragraph 2) 3.1 (paragraph 3 and 4) 3.3.3 (paragraph 1) 6.6 6.8 6.9 (paragraph 1) Units, symbols, terms and definitions General therefore be avoided. The International System of Units (SI) is us
36、ed in these rules; all conversion factors can -_ STD-BSI BS-EN b753-ENGL 1b Lb2qbbS b77352 089 Page 7 EN 60953-2 : 1995 The coherent units for all relevant quantities are given in the Table in 2.2. Some conversion factors are given as well for specific heat rates based on units other than W/W. 2.2 S
37、ymbols, units For the purpose of these rules the following symbols, definitions and units shall be used: )uantity lower low rate ressure. absolute ressure. gauge imbient pressure (barometric) ressure difference bermodynamic temperature :elsius temperature emperature difference lertical distance ipec
38、ific enthalpy kpecific enthalpy of saturated water ipecific enthalpy of saturated steam ipecific enthalpy drop ipecific heat luality, i. e dryness fraction of saturated ,team by weight totational speed deiocity ensity ipecific volume Diameter 4cceleration due to gravity ermal efficiency hermodynamic
39、 efficiency Heat rate Steam rate Heat flow rate Cavitation factor Concentration Correction factor according to 6.60) Correction factor according to 6.66) Isentropic exponent Discharge coefficient Flow coefficient General quantity Weight factor for averaging Confidence limit Relative measuring uncert
40、ainty of x Tolerance of steam table Symbol P Pabs Pe AP T.8 At H h h h“ Ah m Psmb t. e C X n V e V D g VI HR SR 0 K C F F* Vtd K cd LI X 2) Y V Tx = - R VX X Unit W Pa Pa Pa Pa K K m Jlkg Jlkg Jlkg Jlkg kg/s J1kg.K kdy S- m/S kglm3 mlkg m dS2 WIW W/W WIW kg/W.s or kglJ Jls 1 According to nature of t
41、race 1 1 Examples of nultiples and iub-multiples kW kPa k Pa kPa kPa mm kJ/kg kJkg kJ/kg kJlkg kJlkg.K glP mm kWkW kW/kW kWlkW kglkW.s kJ kJ1s Other IS0 units bar I) bar I) lar I). mbar “C min- kJ/kW.s. kJlkW.h kg/kW.h ) Admitted by CIPM and IS0 for temporary use with fluids only. 2, According to ap
42、plication. -SrDrSI BS EN b0953-2-ENGL L97b = Lb24bb7 b79353 TLSE Page 8 EN 60953-2 : 1996 Relation between Heat Rate and thermal efficiency: Units used for HR W/W, kWkW, kJkW * s kJkW-h kJA4w.s kcalkW h BWkW * h 2.3 Subscripts, superscripts and definitions Qu ant it y )wer iitial steam flow rate and
43、 output eam condition and flow rate ondensate and fced Wal Dns and flow rates r condi iubsctipi b a l3 C i mech max 1 2 3 4 e 5 6 7 8 9 10 11 b d a is ir Relation 1 vt HR = 3600 Vt HR = lo00 vt HR = 859 345 VK 3 412.14 rlt HR = HR = Position or definition it generator terminals raken by auxiliaries
44、not drivcn by the turbine (see 4.2.3); (see also I EC w Iet power output: Pg = Pb - Pa it turbine coupling. less power required by turbine auxiliaries, if driven eparately (see 4.2.3) .nternal to the turbine Mechanical losses of pump and pump drive Values for fully opened control valves Directly ups
45、tream of high pressure (HP) turbine stop valve( and the ;team strainer(s) (if any) that are included in the turbine contract 4t exhaust of the turbine HP from which steam passes to the reheater Directly upstream of intermediate pressure IP turbine stop valves At exhaust of the turbine(s) discharging
46、 to the condenser At extraction point of extraction turbine At condenser discharge At inlet to condensate pump At discharge from condensate pump See Figure la At inlet of boiler feed pump At outlet of boiler feed pump At outlet of final feed heater After passage through the condensate pump and any c
47、oolers (oil. pnerator. gadair) included in the contract At outlet from the drain cooler At outlet of air ejector condenser Refers to water taken from the feed-water system to the superheater for regulation of the initial steam temperature Refers to water taken from the feed-water system to the rehea
48、ter for control of the reheated steam tcmperature STD.BS BS EN b0753-2-ENGL 277b 9 Lb24bb7 b77354 951 Position or definition Measurements adjacent to the inlet flange of the condensate system 3r of the evaporator team supplied to glands from a separate source Page 9 EN 60963-2 : 1996 Quantity Supers
49、cript Efficiency I General - - Quantity lake-up water conditions and ow rate iland steam conditions and flow ates Dcfinition Reference value of computer-calculated efficiency Average value Weighted average value dain steam flow rate and con- :entration dass flow rate and concentra- ion Zondenser cooling water Efficiency Enthalpy drop Velocity Static pressure Concentration Test results and guaranteed values Correction Factor F or Fc General use bscripi - m g gl 9 4Y M F core cond inj E R W wi wio t td throat sat wat L B inj O wo S C rn 1,2, : t7 P
