Characterization of the resistance to PWSCC of hydraulic tube- tubesheet expansions. Final report

Technical Report · Wed Jul 01 04:00:00 EDT 1992

OSTI ID:10179378

Gold, R E; Economy, G; Jacko, R J; Harrod, D L

The resistance to primary water stress corrosion cracking (PWSCC) of hydraulically expanded Alloy 600 steam generator tubing, manufactured by the Westinghouse Specialty Metals Division, was evaluated under highly accelerated conditions in a 400{degrees}C steam test environment. These evaluations included microstructural characterizations of all test materials, screening tests with highly stressed reverse U-bends (RUBs), and the testing of internally pressurized hydraulic expansion tube-in-collar mockups. Eighteen heats of archived tubing from an operating nuclear power plant were evaluated; included were heats of Alloy 600 in both the mill annealed (A600 MA) and thermally treated (A600 TT) conditions. Other heats of archived A600 TT tubing, and reference laboratory heats with known corrosion resistance, were also included in various portions of this investigation. Hydraulically expanded mockups of A600 T-F tubing exhibit high resistance to PWSCC in the aggressive steam test environment. Some of the archived A600 MA heats, however, possess low resistance to PWSCC. Shot peening of the ID surfaces of tubes of these latter heats prior to testing was effective in precluding the occurrence of PWSCC. Archived heats of Model F (or F-type replacement) A600 TT steam generator tubing typically exhibit carbide morphologies and distributions consistent with high resistance to PWSCC. These data are in agreement with the performance to date of operating Model F steam generators.

• Research Organization: Electric Power Research Inst., Palo Alto, CA (United States); Westinghouse Electric Corp., Pittsburgh, PA (United States). Nuclear Services Div.
• Sponsoring Organization: Electric Power Research Inst., Palo Alto, CA (United States)
• OSTI ID: 10179378
• Report Number(s): EPRI-TR--100865; ON: UN92040564
• Country of Publication: United States
• Language: English

Related Subjects

21 SPECIFIC NUCLEAR REACTORS AND ASSOCIATED PLANTS
210200
36 MATERIALS SCIENCE
360105
CORROSION AND EROSION
CORROSION RESISTANCE
CRACKS
INCONEL 600
POWER REACTORS
NONBREEDING
LIGHT-WATER MODERATED
NONBOILING WATER COOLED
PWR TYPE REACTORS
STEAM
STEAM GENERATORS
STRESS CORROSION
TEMPERATURE RANGE 0400-1000 K
TUBES