Surface System
AutoTrak’s Surface System has two main elements: Surface Computer System and the By-Pass Actuator
Surface Computer System
The Surface Computer System encodes the downlink signals for transmission tot he tool and decodes the MWD signals received from downhole. It also provides standard directional and LWD outputs. This system includes the central processor and an MWD decoding unit. Downlink communication with the AutoTrak RCLS tool is controlled either by the computer or manually from the keypad. The downhole system is programmed by using the negative pulse telemetry created in the surface By-Pass Actuator.
By-Pass Actuator
The By-Pass Actuator (BPA) valve unit transmits commands to the downhole tool through negative mud pulse telemetry. Each valve unit is fully certified by Det Norske Veritas. The by-pass actuator is connected to the standpipe and can divert some of the mud flow to create a series of negative pulses in the drill pipe. The tool senses and decodes these as downlink instructions. A complete downlink command can take between 2 and 8.5 minutes depending upon the complexity of the downlink. After the AutoTrak RCLS downhole tool receives the downlink information, it sends a confirmation message back to the surface, then reconfigures itself for the task required.
Automated operation of downlink can be performed as drilling proceeds, allowing control of AutoTrak RCLS without interrupting the progress of the well.