| 摘要 |
<p>PURPOSE:To shorten a delay in an inner tube fracture-detecting time, to simplify a system by eliminating a gas circulation system for transporting moisture and to reduce its cost. CONSTITUTION:The inner tube fracture detector for a double tube type steam generator detects a fracture occurring in an inner tube of the generator for a fast breeder reactor. A light emitting unit 30 and a photoreceiver 32 are so disposed at gas plenums 20, 22 of the generator as to be opposed thereto, an infrared ray from a light source 34 is guided to the unit via a heat resistant optical fiber 36, passed through the gas plenums, the infrared ray received by the photoreceiver is guided to a photodetector 38 via a heat resistant optical fiber to be converted into an electric signal, and presence/absence of leakage steam is detected by utilizing an infrared ray absorption due to moisture by a signal processor 40. It is desirable to so dispose many pairs of the units and the photoreceivers that the infrared ray is passed in a matrix state in the gas plenums.</p> |
