Changes

==Swab tests==

==Swab tests==

''Swabbing'' can be defined as pulling a full-diameter tool from the wellbore; this pulling action is similar to that of a plunger in a syringe, and it initiates fluid flow into the wellbore<ref name=pt09r26>Whittaker, A. H., 1987, Mud logging, in Bradley, H. B., ed., Petroleum Engineering Handbook: Richardson, TX, Society of Petroleum Engineers.</ref>. On occasion, oil or gas wells may not flow fluid to the surface on completion. When this occurs, a swabbing unit is run to remove the hydrostatic column of fluid in the wellbore and allow the well to kick off and flow.

''Swabbing'' can be defined as pulling a full-diameter tool from the wellbore; this pulling action is similar to that of a plunger in a syringe, and it initiates fluid flow into the wellbore.<ref name=pt09r26>Whittaker, A. H., 1987, Mud logging, in Bradley, H. B., ed., Petroleum Engineering Handbook: Richardson, TX, Society of Petroleum Engineers.</ref> On occasion, oil or gas wells may not flow fluid to the surface on completion. When this occurs, a swabbing unit is run to remove the hydrostatic column of fluid in the wellbore and allow the well to kick off and flow.

In some oil wells, the bottomhole pressure may be insufficient to lift fluid continuously. Because a surface flow rate cannot be maintained and measured, routine flow and buildup tests cannot be used to evaluate reservoir properties and determine well productivity. In these instances, a swabbing tool can be run at regular intervals to keep fluid flowing from the formation more or less continuously.

In some oil wells, the bottomhole pressure may be insufficient to lift fluid continuously. Because a surface flow rate cannot be maintained and measured, routine flow and buildup tests cannot be used to evaluate reservoir properties and determine well productivity. In these instances, a swabbing tool can be run at regular intervals to keep fluid flowing from the formation more or less continuously.