Evaluation and improvement of PWR secondary-system oxygen control measures. Final report
The phenomenon of denting that has occurred in some PWR steam generators has been attributed to the formation of corrosion products in the crevice region between the tubes and the tube support plates in the steam generator. This corrosion product has been identified as principally magnetite (Fe/sub 3/O/sub 4/) which forms through reaction between iron in the carbon steel tube support plates and oxygen either dissolved in the feedwater or carried by reducible metal oxides in the feedwater. Dissolved oxygen enters the feedwater through leaks in the condenser and other components of the secondary system, particularly valves and pumps. Reducible metal oxides enter after forming as corrosion products in the condenser and other components. This report provides recommendations for equipment and design options, along with associated costs, for making plant modifications that would correct the air-inleakage in most plants. The report also provides an evaluation of the use of hydrazine to scavenge oxygen in secondary systems, and provides recommendations for operating and maintenance practices.
- Research Organization:
- Westinghouse Electric Corp., Pittsburgh, PA (USA). Nuclear Technology Div.
- OSTI ID:
- 5871650
- Report Number(s):
- EPRI-NP-3020; ON: DE83902697
- Country of Publication:
- United States
- Language:
- English
Similar Records
Experimental investigation on denting in PWR steam generators: causes and corrective actions
Effects of oxygen, copper and acid chlorides on denting corrosion
Related Subjects
210200* -- Power Reactors
Nonbreeding
Light-Water Moderated
Nonboiling Water Cooled
BOILERS
CHALCOGENIDES
CHEMICAL REACTIONS
CHEMISTRY
CORROSION
CORROSION DENTING
DEFORMATION
DEPOSITS
IRON COMPOUNDS
IRON ORES
IRON OXIDES
MAGNETITE
MINERALS
MODIFICATIONS
ORES
OXIDE MINERALS
OXIDES
OXYGEN COMPOUNDS
PWR TYPE REACTORS
REACTORS
RETROFITTING
STEAM GENERATORS
TRANSITION ELEMENT COMPOUNDS
TUBES
VAPOR GENERATORS
WATER CHEMISTRY
WATER COOLED REACTORS
WATER MODERATED REACTORS