Successful Completions in the Gulf of Mexico Using the Single-Trip Perforation and Packing System

Abstract As the energy industry continues its advances in deepwater technology and exploration for deeper production reserves, saving pipe trips and minimizing expensive completion fluid losses are two factors of increasing importance. Recent advances in frac-pack and tubing conveyed perforating (TCP) technologies have yielded a tool system design that is simple yet capable of withstanding the rigors of the frac-pack system and TCP. With the single-trip perforation and packing system (STPP), an operator can perforate then immediately frac-pack a well in a single trip, yielding consistently excellent results. If desired, high-rate water fracs and standard gravel packs can be performed with the system. This paper describes the STPP, well control safety issues, completion and production results, and the substantial cost savings of one operator experienced using the system in the Gulf of Mexico. (Fig. 1) Background STPPs have been operable for several years now. After some use in the early 1990s, interest in these systems seemed to wane-until recently. These early system performances produced mixed results for several reasons. Compared to conventional systems. the early STPPs were relatively complicated and seemed to violate the time-proven concept of "keep it simple." Most of the early systems' case histories utilized gravel packing as the method of sand control. Hence, underbalance perforating was needed to help ensure the cleanest possible perforation tunnels. With common underbalance pressures of 750-1200 psi, the predominant problem of sanding up perforating guns increased risk and neutralized the pipe trip and completion fluid savings that would have normally been realized. When using the conventional systems, operators experienced sand production while tripping out of the hole with the perforating assembly and tripping in the hole with the gravel pack assembly. A pipe trip with a mule shoe would clean out the sand in the wellbore, and a lost circulation material (LCM) pill would be spotted thereafter to keep formation sand from again sloughing into the wellbore. Tripping back in the hole with the gravel pack assembly, the operator would again tag unwanted formation debris in the wellbore. In some cases this cycle would be repeated many times before reaching an acceptable depth with the gravel pack assembly. Earlier systems also did not have the capability of isolating the gravel pack packer's hydraulic setting tool from the shock and hydraulic pressures the system experienced while TCP was performed on the zone of interest. This shortcoming sometimes resulted in the hydraulically set gravel pack packer prematurely setting during the perforating operation necessitating fishing the entire assembly before the sand control operation could be performed. The low daily rig rates and relatively low cost of materials such as completion fluids compounded the lack of interest in the early one-trip perforating and gravel packing systems. Finally, well control safety issues during pipe trips were less of a problem during the early 1990s since the experience level of energy industry personnel was very high. Introduction Since the mid-1990s, conditions in the energy industry have changed and continue to do so rapidly.