A slickline is a cable well operators can insert into an oil or gas well to place and remove tools and equipment during well maintenance and service. When not in use, it remains tightly coiled on a drum that operators can turn to pay out lengths of line or take the line back up. Slicklines are used by oil companies as well as firms that specialize in well maintenance. They are not electrical in nature, differentiating them from wirelines, which are capable of transmitting data from inside the well.
The slickline is narrow and tightly braided. The design resists tension to make it possible to pull very hard on the line without the risk of breakage. Tools and well parts may shift during work, and this can create the need to pull firmly to dislodge them. The slickline must be able to resist the pressure without snapping, as a break could result in losing equipment inside the well. This could force operators to lower another slickline to retrieve them.
This line can pass through the control box of an active or live well without disrupting internal pressure. A slickline allows operators to work on a well while it is in active production and can maintain efficiency. It can also be used in a killed well that is not actively producing oil, as in the case of a workover, where personnel perform critical maintenance to make sure a well will be able to continue producing.
Slicklines can carry a variety of tools along with weights to control their performance inside the well. The process of conducting operations with a slickline may be known as slicklining. It can be performed on land or sea, using a variety of support equipment and personnel. While the line is in operation, staff members will inspect it for any signs of damage or compromise to prevent losses and accidents. The line also typically passes through a cleaning system on the way up to remove detritus from inside the well. This keeps operations cleaner and limits exposure to environmental hazards like chemicals that may be present inside the well.
Personnel can learn to operate a slickline on the job. Oil and gas well workers typically start in beginning positions to acquire safety skills and learn about different worker positions through observing. As they develop experience, they can work their way through different roles on the well and will receive training from more experienced mentors.