Capacitive creep strain measurements predict component life

Journal Article · Wed May 01 04:00:00 EDT 1991 · Power Engineering; (United States)

OSTI ID:5285069

Thielsch, H; Knarr, N; Burdick, C ^[1]

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1. Thielsch Engineering Associates Inc. (US)

This paper reports that catastrophic ruptures have damaged four utility hot reheat piping systems. The reason: gradual deterioration during prolonged service at elevated temperatures. Steam leaks in main steam and hot reheat piping, boiler headers and turbine shells also are traced to this condition. Power plant owners increasingly recognize the vulnerability of such components. The rate of deterioration in these components tends to accelerate with time and with increases in temperature. Such deterioration often is associated with creep, which is the gradual elongation, swelling or expansion of alloy steel materials that convey superheated steam. Because metals have a limited creep life, a measure of the amount of creep strain over a period of time may help to determine the remaining life of a component. Creep relates to time in operation at elevated temperatures, as well as localized stresses. For this reason, the amount of creep (or decrease of remaining life) may vary significantly along the length of a main steamline, hot reheat piping system, a superheater or reheater outlet header, or at turbine connections.

• OSTI ID: 5285069
• Journal Information: Power Engineering; (United States), Journal Name: Power Engineering; (United States) Vol. 95:5; ISSN POENA; ISSN 0032-5961
• Country of Publication: United States
• Language: English

Related Subjects

20 FOSSIL-FUELED POWER PLANTS
200100 -- Fossil-Fueled Power Plants-- Power Plants & Power Generation
200104* -- Fossil-Fueled Power Plants-- Components
36 MATERIALS SCIENCE
360103 -- Metals & Alloys-- Mechanical Properties
ALLOYS
BOILERS
CREEP
ELECTRIC UTILITIES
EQUIPMENT
IRON ALLOYS
IRON BASE ALLOYS
MACHINE PARTS
MACHINERY
MECHANICAL PROPERTIES
OPERATION
PIPES
PLANNING
PUBLIC UTILITIES
RELIABILITY
SAFETY
SERVICE LIFE
STEAM LINES
STEELS
STRESS ANALYSIS
STRESSES
TEMPERATURE DEPENDENCE
THERMAL STRESSES
TIME DEPENDENCE
TURBINES
TURBOMACHINERY