MONITORING METHOD OF CORROSION

• Main Authors: MIZUNIWA FUMIO, HONDA TAKU, KASHIMURA EIJI, MAEKOYA CHIAKI, MINATO AKIRA
• Format: Patent
• Language: English
• Published: 05.01.1985
• Edition: 4
• Subjects: INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIRCHEMICAL OR PHYSICAL PROPERTIES; MEASURING; PHYSICS; TESTING

PURPOSE:To monitor corrosion simply by measuring the concentration of manganese ions from the corrosion information of a metallic material containing manganese. CONSTITUTION:A pipe 2 to be used from a primary cooling water system of a BWR nuclear power plant is made of a metallic material containing manganese. When the corrosive state of the pipe 2 is to be monitored, sampling pipes 3, 4 are connected to the inlet and outlet of the pipe 2 and the increment of the concentration of Mn<2+> ions in a flowing fluid 1 is measured. The quantity (m) of corrosion in the whole pipe 2 and the corrosion speed (dm/dt) are found out from equations ( I ), (II) on the basis of said measured value. In these equations, V is the flow rate of the fluid in the pipe, DELTAx is the increment of the concentration of Mn<2+> ions, t is the stay time of the fluid in the pipe, s is the contacting area of the pipe with the fluid, and rho is the concentration (Wt%) of Mn in the pipe material. The concentration of Mn<2+> ions is obtained by measuring the fluid collected by the sampling pipes 3, 4 on the basis of direct absorptiometry.