Leakage detecting device of heat conveying three-layer casing pipe

The utility model discloses a leakage detecting device of a heat conveying three-layer casing pipe. The leakage detecting device comprises an inner pipe of the heat conveying three-layer casing pipe, an inner pipe insulating layer, a middle pipe, an outer pipe, an outer pipe insulating layer, hot water pressure sensors, cold water pressure sensors and a display alarming device. The hot water pressure sensors are installed on the inner wall of the inner pipe, the cold water pressure sensors are installed on the inner wall of the outer pipe, the hot water pressure sensors are installed every 20 m intervals, the cold water pressure sensors are installed every 20 m intervals, the hot water pressure sensors and the cold water pressure sensors are connected to the display alarming device through signal lines, the display alarming device can display the pressure distribution changing situation of the fluid of the inner pipe of the heat conveying three-layer casing pipe and the fluid in an annular pipeline at the same time, and the display alarming device is placed in a control room where a manager is located. When one pressure sensor measures the sudden change of the pressure value, it is shown that the place leaks, then the display alarming device gives an alarm to remind a worker, and the leakage position can be accurately found according to the position where the pressure sensor with the pressure value suddenly changing is located.