摘要 |
A control system (106) is provided for controlling the flow of hydrocarbons out of a production well. The control system has hydraulic decoders which operate a plurality of chokes (116 and 118). The hydraulic decoders (124 and 126) provide actuation signals on receiving hydraulic control pressures within predetermined ranges. The actuation signals operate a hydraulic actuator (120 and 122) to open or close a particular choke. In this way chokes can be operated independently. |