It is now widely recognized that to maximize productivity from certain formations, the well should be perforated underbalanced and control fluids should not be allowed to enter the reservoir during subsequent production operations. During the last few years, tubing-conveyed perforating techniques have been developed for rod pumped wells which allow them to be perforated in an underbalanced condition and then be immediately produced. Thus, completion fluids cannot interact with the formation. The technique described in this paper is an improvement over existing technology. It takes advantage of the fact that insert type sucker rod pumps are easier to run than the tubing string.
This new technique combines the firing head and a bypass assembly with the pump, rather than the tubing and gun string, which allows them to be run and retrieved independently. This improves the safety and operational flexibility of the system since the firing head is not connected to the gun until the moment of firing and the tubing string does not have to be significantly modified for the operation. A light pulling unit or crane is all that is required to retrieve the firing head or to run a subsequent Through Tubing operation.
This paper describes the new equipment and its operation and shows how the unique features of the design have been used to enhance the effectiveness of this type of rod pumped completion. Safety, reliability and cost-effectiveness are discussed. A review of the operational results for a group of wells in the Meleiha Field in Egypt which were completed using this technique is included and mention is made of other potential completion strategies.