Wireline operations are part of special services in the oil and gas industry. The operations include slicklines and electric lines utilized for perforating, logging, bailing, downhole tool setting, fishing, swabbing, and other workover efforts.

Wirelines

A wireline, also called electric line, is an electric cable used to transmit data regarding the conditions of the wellbore and to lower tools into it. It may consist of single or multi-strand cables that are braided. Aside from gathering data for other workover tasks, wirelines are also used to perform wireline logging.

Slicklines A slickline is a thin non-electric cable inserted into a well to deliver and retrieve wellbore tools like gauges, plugs, and valves. It can also be used to adjust valves and sleeves located downhole, and to repair tubing within wellbore. Wrapped around a drum at the back of a truck, the slickline is raised and lowered into the well by reeling the wire in and out hydraulically.

Wireline Logs

Wireline logs measure properties of well formations using electric lines. They were first developed by the Schlumberger brothers in 1927. Wireline logs are constant downhole measurements sent through wirelines to help drillers, engineers, and geologists make real-time decisions about drilling operations – quite different from MWD and mud logs. Wireline logs assess wellbore dimensions and sonic properties, and can measure conductivity, resistivity, and formation pressure.

The logging tool called a sonde is located at the bottom of the wireline. Measurements are taken by lowering the wireline to the prescribed depth and then raising it out of the well. In an effort to sustain tension on the line, measurements are continuously taken on the way up.

Workover Operations

Workover operations cover remedial work to sustain, restore, and/or enhance production. Although frequent, but not necessarily always, workover operations require production shut-in. a well-servicing unit is used in workover operations to haul things in and out