Once the drill string is removed from the hole, wireline or slickline tools can be lowered into the hole. Slickline tools are lowered on a simple steel cable. Typically, slickline is used to set and retrieve simple tools like valves, plugs, and gauges.
In contrast, wireline tools are connected electronically to the surface. This allows them to transmit data up the hole in real time. Wireline tools are used extensively in the formation evaluation process, which we’ll be talking about in the next section of the course.
In either case, the tools are lowered into the well from a large wire spool mounted on the back of a truck.
Images: “Wireline Grease-head” by Schwindj licensed under CC BY SA 4.0