Diagnostics based on thermodynamic analysis of performance of steam turbines: Case histories

Conference · Wed Jul 01 04:00:00 EDT 1998

OSTI ID:20018836

Tirone, G; Arrighi, L; Bonifacino, L

The purpose of this paper is to describe some types of failures which have occurred with the ENEL stock of fossil-fuel steam turbines over the last 5--7 years. This paper also presents the corresponding thermodynamic analysis of turbine parameters which permitted failure diagnosis and pre-scheduled opening of the turbine. The examined failures concern: (1) in-service rupture of the bell seal retainer nut between a SH steam inlet sleeve and the inner HP/IP cylinder, on turbines with a main steam inlet system with bell seals; (2) incorrect assembly of pressure seal rings between steam inlet sleeves and the inner cylinder on turbines with a main steam inlet system with pressure seal rings during a scheduled outage; (3) steam flow path restriction in IP turbine inlet; (4) steam flow path restriction in 1st HP turbine stage nozzles; and (5) steam flow path restriction in 2nd HP turbine stage vanes. Thermodynamic failure analysis and the subsequent analysis of turbine damage (mechanical and financial) enabled condition-based maintenance operations to be carried out.

• Research Organization: ENEL S.p.A., Torino (IT)
• OSTI ID: 20018836
• Report Number(s): CONF-9806214--
• Country of Publication: United States
• Language: English

Related Subjects

20 FOSSIL-FUELED POWER PLANTS
32 ENERGY CONSERVATION, CONSUMPTION, AND UTILIZATION
FAILURES
FOSSIL-FUEL POWER PLANTS
STEAM TURBINES
SYSTEM FAILURE ANALYSIS
THERMODYNAMICS