Abstract: The online monitoring device for combustible gas passing through cable penetrators utilizes active gas sampling technology to achieve online monitoring of cable penetrators in Christmas trees. This device solves the blind spot of no active online monitoring system for cable penetrators on offshore oil production platforms. The sampling pump is mainly controlled by a control circuit to continuously extract gas from the cable penetrator gas sampling box to the combustible gas sensor. The control circuit controls the operation of the sampling pump while controlling the power on or off of the solenoid valves after each Christmas tree passes through the cable penetrator sampling box to achieve single Christmas tree sampling. The system is equipped with a dedicated blowing pipeline and blowing control,ensuring the accuracy of each sampling. This device has an independent control system that independently completes functions such as control,alarm,and communication.

Key words: solenoid valve, online monitoring, combustible gas, sampling pump, PLC