Analyses of first-stage nozzle cracking in General Electric Model 7001B and 7001E industrial gas turbines are presented. Empirical algorithms are developed to predict the maximum extent of cracking that is visible on these nozzles as a function of engine cyclic history and the number of fired hours. It is shown that the algorithms predict this cracking to within a factor of two. Metallurgical analyses of nozzles show that crack growth follows the carbide-matrix interface, environmental attack occurs at the crack tip, and that the microstructure changes by increasing the amount of carbide precipitation, which increases the hardness. These metallurgical results, along with mechanical test data and stress analyses from the literature, are used to understand the nature of nozzle cracking. The maximum extent of cracking coincides with locations of maximum thermal stresses as determined by finite element analyses of similar nozzle designs. This location is at the airfoil-shroud junction on the middle vanes of multivane castings. The use of these algorithms as a predictive maintenance tool and the ability to inspect nozzles visually in the engine also are discussed.
Skip Nav Destination
Article navigation
January 1994
Research Papers
Analysis of General Electric Model 7001 First-Stage Nozzle Cracking
H. L. Bernstein,
H. L. Bernstein
Materials and Mechanics Department, Southwest Research Institute, San Antonio, TX 78228
Search for other works by this author on:
R. C. McClung,
R. C. McClung
Materials and Mechanics Department, Southwest Research Institute, San Antonio, TX 78228
Search for other works by this author on:
T. R. Sharron,
T. R. Sharron
Materials and Mechanics Department, Southwest Research Institute, San Antonio, TX 78228
Search for other works by this author on:
J. M. Allen
J. M. Allen
Combustion Turbines Program, Electric Power Research Institute, Palo Alto, CA 94303
Search for other works by this author on:
H. L. Bernstein
Materials and Mechanics Department, Southwest Research Institute, San Antonio, TX 78228
R. C. McClung
Materials and Mechanics Department, Southwest Research Institute, San Antonio, TX 78228
T. R. Sharron
Materials and Mechanics Department, Southwest Research Institute, San Antonio, TX 78228
J. M. Allen
Combustion Turbines Program, Electric Power Research Institute, Palo Alto, CA 94303
J. Eng. Gas Turbines Power. Jan 1994, 116(1): 207-216 (10 pages)
Published Online: January 1, 1994
Article history
Received:
February 21, 1992
Online:
April 24, 2008
Citation
Bernstein, H. L., McClung, R. C., Sharron, T. R., and Allen, J. M. (January 1, 1994). "Analysis of General Electric Model 7001 First-Stage Nozzle Cracking." ASME. J. Eng. Gas Turbines Power. January 1994; 116(1): 207–216. https://doi.org/10.1115/1.2906794
Download citation file:
Get Email Alerts
Cited By
Study of Injector Geometry and Parcel Injection Location on Spray Simulation of the Engine Combustion Network Spray G Injector
J. Eng. Gas Turbines Power (July 2023)
Fully Coupled Analysis of Flutter Induced Limit Cycles: Frequency Versus Time Domain Methods
J. Eng. Gas Turbines Power (July 2023)
Impact of Ignition Assistant on Combustion of Cetane 30 and 35 Jet-Fuel Blends in a Compression-Ignition Engine at Moderate Load and Speed
J. Eng. Gas Turbines Power (July 2023)
Related Articles
Temperature Estimation and Life Prediction of Turbine Blades Using Post-Service Oxidation Measurements
J. Eng. Gas Turbines Power (October,1997)
Leak Before Break Analysis of Steam Generator Shell Nozzle Junction for Sodium Cooled Fast Breeder Reactor
J. Pressure Vessel Technol (April,2012)
Recent Experience in Examination of High-Temperature Catalytic-Cracking Pressure Equipment
Trans. ASME (October,1952)
Effect of Time and Temperature on Thermal Barrier Coating Failure Mode Under Oxidizing Environment
J. Eng. Gas Turbines Power (March,2009)
Related Chapters
Analysis of Components in VIII-2
Guidebook for the Design of ASME Section VIII Pressure Vessels, Third Edition
Introduction and Definitions
Handbook on Stiffness & Damping in Mechanical Design
Introductory Information
The Stress Analysis of Cracks Handbook, Third Edition