− | ''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. |