In 2008 &2009, Dana Gas continued on their deep Gas development program in the Nile Delta region of Egypt. These wells in the past had proven problematic in drilling because of high formation pressures and compacted shale in some intervals & almost the aligned curves (very narrow window) between the pore pressure & fracture gradient in other intervals.Similar wells drilled in the past required both roller cone and PDC bits to complete the various sections. Because roller cone had unacceptably low ROP, Dana Gas determined PDC would offer the best option to efficiently drill these sections, therefore offering the best chance for success. Contingencies were considered for fallback to roller cone if necessary. Also in the contingency was the use of eccentric Ream While Drilling tool to enlarge the hole across a high pressure zone which would enable us to set an expandable liner and continue drilling to TD with a larger hole and avoid potential problems associated with slim hole drilling.In the preplanning stage, Dana Gas drilling team closely examined new technologies which would allow us to achieve our goals, especially drilling the demanding deep highly pressured zones. The entire BHA was engineered to ensure the ROP and directional requirements would be met. A team was organized to aggressively seek technology/best practices that would efficiently deliver well objectives. The team identified the poor ROP in the compacted shale sections to be a primary obstacle as well as dealing with the potential zone with high pore pressure. BHA and PDC bit technology was a key focuses in optimizing the 12 ¼" and 8 ½" sections. Due to this careful planning and collaboration between Dana Gas and service providers, objective in the 12 ¼" section on SHARABAS-1 and 8 ½" section on EL BASANT-3 wells drilling with new designed PDC was achieved by increasing ROP and realizing significant savings. By applying new technology the 12 ¼" section on SHARABAS-1 was drilled 328% faster with a savings of US$ 122,445.00 and the 8 ½" section on EL BASANT-3 was drilled with a 37% higher ROP with a savings of US$ 34,517.00 than the direct offsets.

The practice of deep-well drilling (i.e., reaching depths of 15,000 ft or more) has been increasing for more than three decades with well costs increasing as record depths are continually challenged. The demand for gas has generally supported this drilling activity, nevertheless the pursuit for drilling the most economical well continues. This paper presents a case history of cementing a long, intermediate casing string. Such casing strings are strategically placed covering a large section of the drilled hole straddling as close as possible between the lowest fracture gradient and the highest pore pressure in the drilled section. Such a design helps minimize the number of casing strings required for the well, thus helping to reduce the well cost. While it might be possible to drill the hole by maintaining a balancing act between flow and loss situations, the cementing challenges remain to be tackled. The use of foamed cementing has addressed the issue of cementing in a lost-circulation situation and controlling the flow from a gas zone found within the same interval. When compared to conventional cement jobs, foamed cement was not only superior in technical design but provided several cost-saving benefits that many potential users might be unaware of. For example, the bulk cement-volume requirement dropped by a factor of 1.72, provided a cost saving of approximately 35 to 40%, and reduced the bulk equipment footprint from 1,560 ft2 to 936 ft2. The job-time also decreased by three hours. These discrete savings combined are significant. Though this solution brings much benefit to operators, it is still regarded as an unconventional cementing solution. This paper provides a case history, economic analysis, physical properties, and developmental background of foamed cementing that should help operators see its benefit and use.

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