Patent ID: 8678031

Claim:
A pipe-passivating alkali-injecting device for use in a nuclear plant, the pipe-passivating alkali-injecting device including: an alkali-injecting tank ( 1 ) filled with a proper amount of alkali; an actuator ( 2 ); a counter-balance valve ( 3 ); a first pipe ( 21 ) for connecting the alkali-injecting tank ( 1 ) to the actuator ( 2 ); wherein the first pipe ( 21 ) is an L-shaped pipe including: a first section ( 211 ) extending from the alkali-injecting tank ( 1 ); and a second section ( 212 ) tilting by an angle of 30 degrees toward the actuator ( 2 ); a second pipe ( 22 ) for connecting the counter-balance valve ( 3 ) to the actuator ( 2 ); a third pipe ( 31 ) for connecting the counter-balance valve ( 3 ) to the alkali-injecting tank ( 1 ); a fourth pipe ( 41 ) for connecting the counter-balance valve ( 3 ) to a pump ( 7 ) of the nuclear plant; a pressure gauge ( 4 ) arranged on the second pipe ( 22 ); exhaust valves ( 5 ) arranged on the first and fourth pipes ( 21 , 41 ); and switching valves ( 6 ) arranged on the first and fourth pipes ( 21 , 41 ).