skip to main content
OSTI.GOV title logo U.S. Department of Energy
Office of Scientific and Technical Information

Title: An Investigation of the Mechanism of IGA/SCC of Alloy 600 in Corrosion Accelerating Heated Crevice Environments: Topical Report - Results for Mod of Heated Crevice - 08/18/1999 - 08/31/2000

Technical Report ·
DOI:https://doi.org/10.2172/769287· OSTI ID:769287

A pressurized water reactor (PWR) steam generator transfers heat from the primary water, heated in the reactor core, to the secondary coolant system. These are shell and tube heat exchangers having the primary water from the reactor inside the tubes and with steam generation on the shell side. This design generates steam on the OD side of the Alloy 600 (or Alloy 690) steam generator tubes, which leads to the concentration of impurities (referred to as hideout) in occluded regions on the tubes. Of major concern is the crevice formed by the tube/tube support plate (T/TSP) intersection. The restricted mass transport in the small crevice volume prevents the species, which concentrate during the generation of steam on the OD of the tube, from quickly dispersing into the bulk water. The presence of a porous magnetite corrosion product from the support plate and deposits, originating from the feed and condenser systems, in the crevice further restricts mass transport, enhancing the concentrating process. This flow restriction leads to the concentration of impurities from the steam generator water by a thermal hydraulic mechanism.

Research Organization:
Rockwell Science Center LLC, Thousand Oaks, CA (US)
Sponsoring Organization:
US Department of Energy (US)
DOE Contract Number:
FG03-99SF21921
OSTI ID:
769287
Resource Relation:
Other Information: PBD: 1 Nov 2000
Country of Publication:
United States
Language:
English