Casing pipe gas fixed-point on-line monitoring system

The utility model discloses a casing pipe gas fixed-point on-line monitoring system which comprises a gas collecting pipeline, a detecting box, a detecting device, magnetic valves and a remote monitoring device, wherein the gas collecting pipeline is communicated with an oil well casing pipe, the detecting box is provided with a gas inlet and a gas outlet, the detecting device is fixed on the inner wall of the detecting box, the magnetic valves include an inlet valve, an outlet valve and a straightway valve, the inlet valve is installed between the gas inlet and the gas collecting pipeline, the outlet valve is installed between the gas outlet and the gas collecting pipeline, the straightway valve is installed on the part, between the inlet valve and the outlet valve, of the gas collecting pipeline, and the remote monitoring device receives detecting signals sent by the detecting device. According to the casing pipe gas fixed-point on-line monitoring system, fixed-point and timely monitoring is achieved through the control of the magnetic valves and the detecting device, gas channeling can be found out more accurately and timely, the probability of occurrence of accidents caused by the gas channeling is reduced, a large amount of expenditure is saved, and accidents, probably occurring during monitoring, such as poisoning of personnel are avoided.