Patent ID: 8479565

Claim:
A fluid leakage detecting system comprising: a fluid conveying tube comprising: a tube member that is a corrugated metallic tube having flexibility; a heat insulating layer provided on the outer periphery of the tube member: an optical fiber continuously wound around the heat insulating layer; a coupling section provided at an end portion of the tube member; and leakage information transmission means provided in the vicinity of the coupling section and being capable of transmitting, to the outside of the coupling section, leakage information of fluid which flows through the tube member, wherein: the leakage information is gas pressure or gas concentration; the leakage information transmission means transmits the gas pressure or gas concentration in the vicinity of the coupling section to the outside of the coupling section via a terminal provided in the vicinity of the coupling section; and the leakage information transmission means detects the gas pressure or gas concentration in the vicinity of the coupling section via a hollow pipe communicating with the heat insulating layer; a plurality of optical fibers are provided in the fluid conveying tube: and an optical pressure sensor connected to the leakage information transmission means; and an optical pressure sensor converter for converting information output from the optical pressure sensor to pressure information, wherein: the optical fiber is connected to a temperature measurement device and functions as an optical fiber temperature sensor, wherein leakage of the fluid from the tube member is detected from a temperature distribution measured by the optical fiber temperature sensor; leakage of the fluid from the tube member in the vicinity of the coupling section is detected from leakage information transmitted from the leakage information transmission means; a portion of the plurality of optical fibers is connected to the temperature measurement device and functions as the optical fiber temperature sensor; and the remaining optical fiber(s) is connected to the optical pressure sensor converter and functions as a medium for transmitting information from the optical pressure sensor.