Abstract:
As part of the water chemistry surveillance program for Multi Purpose Research Reactor (MPR) G.A. Siwabessy 30 MW, the effects of primary water on homogeny, galvanic and crevice corrosion have been studied using various coupons in order to better control the corrosion in the reactor system. [4,5] The main objectives are to establish standard procedures for corrosion monitoring and surveillance, and provide technical guidelines for
continued wet storage of spent fuels. After having defined the current water chemistry profile, experiments were conducted using the coupons made of the same grade materials as used for the construction of the fuel cladding (aluminium) and reactor tank (aluminium), and fuel storage racks (stainless steel). The test coupons were made of a series of discs (φ95 mm with φ15 mm centre hole; 1 mm thick for stainless steel and 5.5 mm thick for aluminium) put together as an assembly using a stainless steel centre pin and insulated with a ceramic bushing and 5 mm thick spacers between the discs. The coupons are also assembled in two orientations to allow vertical and horizontal installations in the pool. The first batch of six coupon assemblies were strategically positioned in the service pool in January 2007 and are due to be withdrawn in stages for inspection after 1, 2, and 3 years of exposure. This paper describes the current water chemistry and surveillance program.