Intervention robot sealed in a well

摘要

A system for performing interventions in wells comprises a robot 150 sealed in a well. Preferably, the robot is a tractor unit tethered to control electronics also located within the well, allowing autonomous operation without support from a surface vessel. The robot may have an arm for operating sleeve valves, carries a buoyant indicator body (204, figure 12) to be released in case it gets lodged in the well and is capable of collapsing to free itself. It can be used in conjunction with a tool carousel (figure 3) and is particularly useful for carrying tools into low angle or horizontal wells.