This paper will discuss a new technology that installs perforated casing and sand control in a single trip. The system incorporates telescoping perforations containing sand control media into ordinary API casing, run into the hole on standard liner hanger equipment. Applications for this technology include both producers and injectors, particularly those needing zonal isolation.
The key aspects of this technology, particularly the sand control media, sealing wax/polymer, and flow-actuated landing collar, will be discussed in great detail. Critical laboratory testing, along with the associated learnings and contingency plans for the first field installation, will also be reviewed. Finally, the installation procedures and operational review of the first field installation will be covered in detail.
The information presented in this paper is applicable to production and injection wells in sand producing formations.
A new completion technology has been developed that eliminates the need for perforating and for pumping sand control media.
A one-trip sand control completion method that has zonal isolation capability has been developed.
New one-trip sand control completion technology offers a large potential for significant capital expenditure savings.
Risk factors that affect well productivity of cased and perforated wells fall into three major areas:
inflow performance;
effects of near-wellbore damage; and
effects of perforation damage.
Generally, the greater the area open to flow through a perforation tunnel, the greater the productivity of the well. A larger entry-hole diameter will allow an increase in the area open to flow. Conversely, a decrease in flow area may restrict the amount of flow through a perforation tunnel. Similarly, a lower shot density could result in a decrease in total flow area for production. Increasing the shot density equates to a larger effective flow area. And, perforation tunnels must be open so they can be filled with gravel pack sand to prevent filling with formation sand. If the formation sand is lodged in the perforation tunnel, the pressure drop in the perforation is extreme and could adversely affect the well productivity.
Once in place, drilling and completion fluid-induced damage can be the most difficult type of formation damage to remove. Deep penetrating perforating charges can bypass the formation damage caused by drilling and completion fluids, but the ensuing perforation tunnels are more susceptible to skin damage and fines infiltration, which could adversely affect on well productivity.
The crushed zone caused by the explosive discharge in a perforation tunnel can restrict flow from the formation into the perforation. This flow restriction from the formation can significantly decrease well productivity and increase the overall skin of the well. Perforation debris has also been found to cause decreases in well productivity simply because the debris decreases the available inflow area.
The history of formation damage caused by perforating has been well documentedi.
