Innovative Downhole Design for Optimizing ALS Installation at Shale Oil Wells

Abstract

The aim of this paper is to show how tubing (TBG) installation has evolved, with the problems and learning processes experienced along the brief history of exploitation of the Vaca Muerta formation in the Loma Campana field. The production behavior of wells from Vaca Muerta consists initially of flows close to 100m3/d, with sufficient pressure to produce natural flowing by the 5" casing, controlled by an orifice at wellhead. Once the flowing period finishes, the well starts using mechanical pumping to keep producing with this system in the long term. Wells with a higher gas oil rate (GOR) are converted to plunger lift before resorting to mechanical pumping. Due to the fact that a well experiences different extraction stages in a relatively short period of time (flowing by casing - flowing by TBG - Plunger Lift - mechanical pumping), it is necessary to find an installation that is flexible enough to allow switching from one stage to the other with the least amount of slickline and pulling interventions. Likewise, the installation should be able to minimize the effects of sand and gas existing in Vaca Muerta, which affect the performance of mechanical pumping. Thus, this paper shows how TBG installations have changed to finally reach the current installation. This installation allows the conversion of a flowing by TGB installation into a mechanical pumping installation with gas buster, poor boy type, using slickline intervention and pump and rod running, thus avoiding the necessity of moving the TBG.