| 摘要 |
PURPOSE:To automatically control the level of liquid in the freight tank of a low-temperature liquefied gas carrying ship, by using a control mechanism having received a detection signal of vapor or the like generated in the freight tank, to operate a control valve provided in the branch pipe of a liquid return pipe. CONSTITUTION:Gas flow rate sensors 5 are provided in the branch pipes 3' of a gas intake pipe 3, which communicate with freight tanks 1. Gas quantity detection signals produced through the measuring actions of the sensors 5 are sent to a controller 6 to cumulate the gas flow rates to determine the decreases in the quantities of liquid in the tanks 1 and the total amount of reliquefied gas. When the number of liquid-returned freight tanks is plural, flow rate sensors 7 are provided in the branch pipes 4' of a liquid return pipe 4, which communicate with the freight tanks 1. Detection signals are also sent from the sensors 7 to the controller 6 to cumulate the quantities of liquid returned to the tanks 1, to grasp the quantity of liquid in each tank. Control valves 8 provided in the branch pipes 4' of the liquid return pipe 4 are opened or closed according to instructions from the controller 6 to automatically regulate the quantity of liquid which is to be returned to each freight tank 1. |
