1、AN AMERICAN NATIONAL STANDARD ASME TDP-22012Prevention of Water Damage to Steam Turbines Used for Electric Power Generation: Nuclear-Fueled Plants(Revision of ANSI/ASME TDP-21985)ASME TDP-22012(Revision of ANSI/ASME TDP-21985)Prevention of WaterDamage to SteamTurbines Used forElectric PowerGeneratio
2、n:Nuclear-Fueled PlantsAN AMERICAN NATIONAL STANDARDThree Park Avenue New York, NY 10016 USADate of Issuance: April 10, 2012This Standard will be revised when the Society approves the issuance of a new edition.ASME issues written replies to inquiries concerning interpretations of technical aspects o
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11、ent may be reproduced in any form,in an electronic retrieval system or otherwise,without the prior written permission of the publisher.The American Society of Mechanical EngineersThree Park Avenue, New York, NY 10016-5990Copyright 2012 byTHE AMERICAN SOCIETY OF MECHANICAL ENGINEERSAll rights reserve
12、dPrinted in U.S.A.CONTENTSForeword ivCommittee Roster . vCorrespondence With the TWDP Committee . vi1 Scope . 12 Criteria 13 Design 44 Operation . 265 Testing, Inspection, and Maintenance . 276 Conclusion 28Figures1 Typical Heater Steam Side Isolation System: Local Control System . 72 Typical Heater
13、 Steam Side Isolation System: Integrated Control System 83 Typical Heater Tube Side Isolation System: Local Control System 94 Typical Heater Tube Side Isolation System: Integrated Control System . 105 Typical Deaerator Arrangement With Drain System: Local Control System . 146 Typical Deaerator Arran
14、gement With Drain System: Integrated Control System . 157 Typical Deaerator Arrangement With Inlet Isolation: Local Control System . 168 Typical Deaerator Arrangement With Inlet Isolation: Integrated Control System 179 Main Turbine: Typical Steam Seal Arrangement 1810 Typical Arrangement for a Feed
15、Pump Turbine Steam Supply WithDual Admission 2011 Typical Continuous Drain Orifice . 2012 Typical Drain System With Redundant Level Elements . 2113 Typical Condenser Drain Manifolds . 23Table1 Symbol Legend . 4iiiFOREWORDIn the late 1960s, a substantial increase in the number of reported occurrences
16、 of steam turbinedamage by water induction precipitated design recommendations from the two major U.S. steamturbinemanufacturersasanattempttoreducesuchincidents.Consequently,utilitiesanddesignersbegan formulating their own design criteria because of the economic need to keep the generatingunits in s
17、ervice. Realizing the common need for a uniform set of design criteria to alleviate thisproblem, an ASME Standards Committee was formed, consisting of representatives of utilities,equipment manufacturers, and design consultants, to develop recommended practices for use inthe electric generating indu
18、stry.ASMETDP-1,resultingfromtheworkanddeliberationoftheTurbineWaterDamagePreventionCommittee, was approved as a standard of ASME by the ASME Standardization Committee andthe ASME Policy Board, Codes and Standards, on July 26, 1972.In1979,theCommittee proposedarevisiontothisStandard toincludeinformat
19、iononcondensersteam and water dumps, direct contact feedwater heaters, and steam generators. This proposedrevision was approved by the ASME Standardization Committee on April 25, 1980.In 1985, it was decided to issue separate documents for fossil-fueled and nuclear-fueled plants.TDP-1, covering foss
20、il-fueled plants, was approved as an American National Standard onSeptember 13, 1985.ASME TDP-2, written by the same ASME committee, is a comparable document to coverturbines used with light water nuclear-fueled steam supply systems that produce nominally dry-and-saturated steam. This Standard, resu
21、lting from the work anddeliberation of the Turbine WaterDamage Prevention Committee, was approved by the American National Standards Institute onOctober 15, 1985.In 1994, the ASME Board on Standardization approved the disbandment of the Committee onTurbine Water Damage Prevention and the withdrawal
22、of TDP-1. This was due to perceived lackof interest/use by the industry.Subsequent interest from users and potential users for TDP-1 convinced ASME to reconstitutethe Committee under the Board on Pressure Technology Codes and Standards in June of 1997.As a result of this committees work, TDP-11985 w
23、as revised and approved as an AmericanNational Standard on June 17, 1998.The 2006 version of TDP-1 was issued to incorporate combined cycle, multiple steam generators,cycling, and cogeneration technology and to incorporate the capabilities of modern plant instru-mentation and control systems. TDP-1
24、was approved as an American National Standard onNovember 6, 2006.Based on the renewed interest in light water nuclear-fueled steam supply systems, theCommittee began work on a revision of TDP-21985. This Standard was approved as an AmericanNational Standard on March 7, 2012.ivASME TWDP COMMITTEETurb
25、ine Water Damage Prevention(The following is the roster of the Committee at the time of approval of this Standard.)STANDARDS COMMITTEE OFFICERSL. A. Kielasa, ChairR. G. Narula, Vice ChairT. W. Schellens, SecretarySTANDARDS COMMITTEE PERSONNELJ. C. Boyle, FM GlobalA. Atoui, Alternate, FM GlobalV. C.
26、Buquoi, Siemens EnergyM. Heue, Alternate, Siemens EnergyA. M. Donaldson, WorleyParsonsJ. C. Archer, Alternate, WorleyParsonsG. M. Golden, EPRIS. I. Hogg, Contributing Member, University of DurhamL. A. Kielasa, Detroit Edison Co.vR. A. Masten, Sargent however, they shouldnot contain proprietary names
27、 or information.Requests that arenot in this format may berewritten in the appropriate formatby the Committeeprior to being answered, which may inadvertently change the intent of the original request.ASME procedures provide for reconsideration of any interpretation when or if additionalinformation t
28、hat might affect an interpretation is available. Further, persons aggrieved by aninterpretation may appeal to the cognizant ASME Committee or Subcommittee. ASME does not“approve,” “certify,” “rate,” or “endorse” any item, construction, proprietary device, or activity.Attending Committee Meetings. Th
29、eTWDPStandardsCommittee regularlyholdsmeetingsthatare open to the public. Persons wishing to attend any meeting should contact the Secretary ofthe TWDP Standards Committee.viASME TDP-22012PREVENTION OF WATER DAMAGE TO STEAM TURBINES USEDFOR ELECTRIC POWER GENERATION: NUCLEAR-FUELED PLANTS1 SCOPEThis
30、 Standard includes practices that are concernedprimarily with the prevention of water damage to steamturbines used for water-cooled nuclear reactor powergeneration. The practices cover design, operation,inspection, testing, and maintenance of those aspectsof the following power plant systems and equ
31、ipmentconcerned with the prevention of water induction intosteam turbines and the safe removal of water from steamturbines and the following associated systems andequipment:(a) main steam and bypass systems, piping, anddrains(b) turbine extraction systems, piping, and drains(c) turbine steam seal sy
32、stems, piping, and drains(d) feedwater heaters, piping, and drains(e) turbine drain systems(f) condenser steam and water dumps(g) start-up systemsAny connection to the turbine is a potential source ofwater either by induction from external equipment or byaccumulation of condensed steam. The sources
33、treatedherein specifically are those found to be most frequentlyinvolved in causing damage to turbines. Although waterinduction into the high- and intermediate-pressure tur-bines has historically been recognized as the most dam-aging, experience has shown that water induction inlow-pressure turbines
34、 can cause significant damage andshould also be taken seriously.This Standard is not intended to impose new require-ments for existing facilities retroactively.2 CRITERIA2.1 Basis2.1.1 The normal practice for the prevention ofturbine water damage shall be to(a) identify systems that have a potential
35、 to allowwater to enter the turbine(b) design, control, maintain, test, and operate thesesystems in a manner that prevents accumulation ofwater2.1.2 Because of thelower main steam temperaturefrom these types of steam supply systems, much of the1steam path of the turbine contains wet steam. The tur-b
36、ine manufacturer designs for continuous removal of apart of this water at various stages in the turbine. ThisStandard indicates means of removing water from theturbine and preventing its reintroduction once it is inthe external piping. It alsoindicates means of preventinginductionofwaterintotheturbi
37、nefromexternalsources,such as the main steam system and feedwater heaters.The methods for preventing turbine water damage dueto water induction or accumulation include one or moreof the following basic procedures for design whereappropriate:(a) detection of the accumulation of water either inthe tur
38、bine or preferably external to the turbine beforethat water has caused damage(b) isolation of the water by manual or preferablyautomatic means after it has been detected(c) disposal of water either by manual or preferablyautomatic means after it has been detected2.1.3 No single failure of equipment
39、shall resultin water entering the turbine. The failure mode of thevarious devices used to prevent water induction shallbe considered so that a single failure of the signals (lossof air or electrical signal) will not result in water enteringthe turbine.2.1.4 Steam lines connecting to the steam turbin
40、edirectly or indirectly shall be designed to ensure that anysaturated steam or condensate that may have collectedwhile the line or portion of the line that was out ofservice is adequately warmed and drained prior to beingreturned to service.2.1.5 Any automatic control system used to controlsteam lin
41、e drain valves identified in this Standard shallbe designed so that the system has a means for initiatingvalve actuation and a separate means to verify theappropriateness of the automatic action. If an inappro-priate action is taken, an alarm shall be provided.2.1.6 An integrated control system (ICS
42、), such asa distributed control system (DCS), can by its inherentdesign provide additional control and monitoring capa-bility for power plant systems and equipment. Use ofan ICS has been considered as an option for control andmonitoring potential sources that might allow water toenter the turbine. I
43、f an ICS is available, the additionalASME TDP-22012redundancy and availability of that system shall be usedas indicated in this Standard. However, if no ICS isprovided, following the nonICS-specific requirementsis intended to still represent a conservative design forprotection from water induction.2
44、.2 Definition of Terms2.2.1 Systemsauxiliary steam: a steam system that is used outside ofthe main cycle systems for plant uses, such as equipmentpower drives, air heating, building heating, start-upheating, etc.condensate: the main cycle piping system that transportswater from the condenser to the
45、deaerator, feedwatersystem, or steam generator. Heating and purification ofthe water may be part of this system.condenser: equipment that condenses low-pressure tur-bine exhaust steam and thus provides a heat sink forthe cycle. Normally, a condenser also serves to collectthe condensate into a hotwel
46、l to supply the condensatesystem. Condensers may be of the following types:air cooled, condenser: the turbine exhaust steam isrouted to large heat exchangers arranged so that coolingairpassesthrough themandsteamis condenseddirectly.The condensate is collected ina drain tank that functionsas the hotw
47、ell for condensate system supply.auxiliary, condenser: a condenser is designated as auxil-iary when it is supplied primarily for steam-turbine-driven auxiliary equipment or for steam dumps.direct contact, condenser: condensate from the con-denser is routed to a closed cooling heat exchanger andthen
48、returned, where it contacts the steam to continuethe condensing process.water-cooled, condenser: this condenser, the most com-mon type, is supplied with cooling water from a naturalsource or a cooling tower.wet-dry, condenser: a cooling tower combinationemploys an evaporative cooling system (water-c
49、ooled)for a portion of the cooling and includes an air-cooledsection for the remaining cooling.continuous drain: a drain that does not contain a valve,trap, or other device to cycle and pass drainsintermittently.cross-around: a generic term for cross-over or cross-underpiping located between the high-pressure turbineexhaust and the moisture separator, or moistureseparator/reheater (MS or MS/R) or between themoisture separator, or moisture separator/reheater (MSor MS/R) and the low-pressure turbine inlets as definedabove. Cross-around piping could also refer to the pip-ing bet
