Well Production Enhancement Using an Underpump Stem Subjected to Load

Abstract

The method of dynamic loading of sucker-rod pumps to act upon the producing well bottom zone is described. The effect is exerted through an underpump stem set on the well bottom. Under the weight of the flow string, the underpump stem loses pitch stability and is pressed to the inner surface of casing pipes. The operating sucker-rod pump induces axial vibration in the string, which generates lateral stresses transmitted to the adjacent rock mass along the spiral contact line between the underpump stem and the casing pipes. This dynamic impact on inactive or slightly active interlayers invokes fluid flow in them and results in enhanced production of wells. The field test data are presented to illustrate the described effect in wells in different geological conditions.