Abstract: A steam injector system comprises a plurality of steam injectors each being provided with with a check valve adapted for water supply, a check valve adapted for steam supply, a check valve adapted for overflow and a check valve adapted for discharge and the respective water check valves, steam check valves, overflow check valves and discharge check valves are connected. In another aspect, a steam injector system comprises a plurality of first to last stage steam injectors arranged in series with each other, the last stage steam injector being provided with a relief valve disposed at a last stage overflow drain port, and a pressure pulsation absorbing device is disposed at least between the last stage overflow drain valve and the relief valve.

Abstract: In pressure suppression apparatus of a nuclear reactor of the type comprising a vessel surrounding a reactor pressure vessel and containing a water pool at the bottom of the vessel, and a steam exhaust pipe having one end immersed and opened in the water pool, there is provided with an exhaust chamber connected to the immersed portion of the exhaust pipe and provided with a number of discharge openings.