Steam Turbines in Combined Cycles

Performance Test Codes

AN A MERICAN NA TIONAL S T AND ARD

Steam Turbines in Combined Cycles

Performance Test Codes

AN AMERICAN NATIONAL STANDARD

Three Park Avenue • New York, NY • 10016 USA

Date of Issuance: October 21, 2011

This Code will be revised when the Society approves the issuance of a new edition.

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The American Society of Mechanical Engineers Three Park Avenue, New York, NY 10016-5990

Copyright © 2011 by

THE AMERICAN SOCIETY OF MECHANICAL ENGINEERS

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CONTENTS

Notice v

Foreword vi

Committee Roster vii

Correspondence With the PTC Committee viii

Mandatory Appendix

I Correction Formulation Methodology 53

Nonmandatory Appendices

1. Sample Test Calculation 59

2. Sample Test Uncertainty Calculation 79

3. Procedures for Determining HP to IP Leakage Flow 87

   NOTICE

   
   

   All Performance Test Codes must adhere to the requirements of ASME PTC 1, General Instructions. The following information is based on that document and is included here for emphasis and for the convenience of the user of the Code. It is expected that the Code user is fully cognizant of Sections 1 and 3 of ASME PTC 1 and has read them prior to applying this Code.

   ASME Performance Test Codes provide test procedures that yield results of the highest levelof accuracy consistent with the best engineering knowledge and practice currently available. They were developed by balanced committees representing all concerned interests and specify procedures, instrumentation, equipment-operating requirements, calculation methods, and uncertainty analysis.

   When tests are run in accordance with a Code, the test results themselves, without adjustment for uncertainty, yield the best available indication of the actual performance of the tested equipment. ASME Performance Test Codes do not specify means to compare those results to contractual guarantees. Therefore, it is recommended that the parties to a commercial test agree before starting the test and preferably before signing the contract on the method to be used for comparing the test results to the contractual guarantees. It is beyond the scope of any Code to determine or interpret how such comparisons shall be made.

   FOREWORD

   
   

   ASME Performance Test Code 6 on Steam Turbines is most directly targeted for application to steam turbines in regenerative feedwater heater cycles. A Performance Test Code has heretofore not existed to provide procedures for the accurate testing of steam turbines in a Combined Cycle application. The procedures for testing a steam turbine in a Combined Cycle differ from those used to test a steam turbine in a regenerative feedwater heater cycle because of differences in cycle configuration and test objectives.

   In recognition of these differences and to facilitate testing of Steam Turbines in Combined Cycle Applications, the ASME Board on Performance Test Codes approved the formation of a committee (PTC 6.2) on June 7, 2000, with the charter of developing a code for testing of Steam Turbines in Combined Cycle Applications. The resulting committee included experienced and qualified users, manufacturers, and general interest category personnel from the domestic regulated, the domestic nonregulated, and the international electric power generating industry. The organizational meeting of this committee was held on August 15 and 16, 2000.

   In developing the first edition of this Code, the Committee reviewed industry practices with regard to determin- ing the performance of a steam turbine in a combined cycle application. The Committee strived to develop an objec- tive code that addresses the need for explicit testing methods and procedures while providing maximum flexibility in recognition of the wide range of combined cycle applications and testing methodologies.

   The first edition of this Code was approved by the PTC 6.2 Committee on October 24, 2003. It was then approved and adopted by the Council as a Standard practice of the Society by action of the Board on Performance Test Codes on January 13, 2004. It was also approved as an American National Standard by the ANSI Board of Standards Review on August 6, 2004.

   This revision was undertaken at the Committee meeting on March 6 and 7, 2006. This revision accomplishes the following changes:

   1. it amplifies the section on degradation thus providing more useful guidance

   2. provides more guidance on correlated and uncorrelated uncertainty

   3. addresses stability criteria — such as off-design limits of pressure and temperature

   4. adds references to relevant Codes such as PTC 19.5 and PTC 19.6

   5. complies with PTC 1 and the PTC 1 Template

   6. provides an expanded Nonmandatory Appendix C (formerly D) on the procedure for determining N2 packing leakage flow

   7. revises many recommendations in Section 3 to requirements, i.e., use of shall instead of should

This revision does not include Mandatory Appendix II, Procedure for Fitting a Calibration Curve of an Orifice- Metering Run and Nonmandatory Appendix C, Sample Flow Calculations for Differential Pressure Meter. It was reasoned that the issuance of the revised PTC 19.5, Flow Measurement, provided much of the corresponding infor- mation found in these deleted appendices.

This revision was approved by the Council as a Standard practice of the Society by action of the Board on Standardization and Testing on April 1, 2011. It was also approved as an American National Standard by the ANSI Board of Standards Review on June 28, 2011.

ASME PTC COMMITTEE

Performance Test Codes

(The following is the roster of the Committee at the time of approval of this Code.)

STANDARDS COMMITTEE OFFICERS

J. R. Friedman, Chair

J. W. Milton, Vice Chair

J. H. Karian, Secretary

STANDARDS COMMITTEE PERSONNEL

P. G. Albert, General Electric Co. S. J. Korellis, Electric Power Research Institute

R. P. Allen, Consultant M. P. McHale, McHale & Associates, Inc.

J. M. Burns, Burns Engineering Services, Inc. P. M. McHale, McHale & Associates, Inc.

W. C. Campbell, Southern Company Services, Inc. J. W. Milton, RRI Energy, Inc.

M. J. Dooley, Alstom Power, Inc. S. P. Nuspl, Babcock & Wilcox Co.

J. R. Friedman, Siemens Energy, Inc. R. R. Priestley, General Electric Co.

G. J. Gerber, Consultant S. A. Scavuzzo, Alternate, Babcock & Wilcox Co.

P. M. Gerhart, University of Evansville J. A. Silvaggio, Jr., Siemens Demag Delaval Turbomachinery, Inc.

T. C. Heil, Consultant W. G. Steele, Mississippi State University

R. E. Henry, Sargent & Lundy, Inc. T. L. Toburen, T2E3, Inc.

J. H. Karian, The American Society of Mechanical Engineers G. E. Weber, Midwest Generation EME LLC

D. R. Keyser, Survice Engineering W. C. Wood, Duke Energy, Inc.

T. K. Kirkpatrick, Alternate, McHale & Associates, Inc.

PTC 6.2 COMMITTEE — STEAM TURBINES IN COMBINED CYCLES

M. P. McHale, Chair, McHale & Associates, Inc. K. M. Kenneally, MPR Associates, Inc.

T. K. Kirkpatrick, Alternate, McHale & Associates, Inc. K. R. Price, Senior Equipment Specialist

J. H. Karian, Secretary, The American Society of Mechanical Engineers K. D. Stone, Sage Energy Group

A. E. Butler, GE Power Systems W. C. Wood, Duke Energy, Inc.

P. G. Albert, Alternate, General Electric Co. J. Zachary, Bechtel Power Corp.

S. Dinkar, Siemens Power Generation J. A. Zoller, Black & Veatch

J. R. Friedman, Siemens Energy, Inc. Z. Yi, Contributing Member, Thermal Power Research Institute Co., Ltd.

CORRESPONDENCE WITH THE PTC COMMITTEE

General. ASME Codes are developed and maintained with the intent to represent the consensus of concerned interests. As such, users of this Code may interact with the Committee by requesting interpretations, proposing revi- sions, and attending Committee meetings. Correspondence should be addressed to:

Secretary, PTC Committee

The American Society of Mechanical Engineers Three Park Avenue

New York, NY 10016-5990

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ASME PTC 6.2-2011

STEAM TURBINES IN COMBINED CYCLES