| Autor: |
Mustafa Khayari, Hassan Ali Rashid Al Kiyumi, Anwar Adawi, Jeroen Smit, Mohammed Abri, Faisal Al Hinai, Hamada Yousef, Naidu Nakireddi |
| Rok vydání: |
2017 |
| Předmět: |
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| Zdroj: |
Day 1 Mon, November 13, 2017. |
| DOI: |
10.2118/188629-ms |
| Popis: |
This paper discusses the journey of drilling excellence in Khulud field, one of the most challenging fields in Sultanate of Oman and the Middle East. It highlights the changes in well design, drilling optimization and efficiency improvement which resulted in significant cost and time improvement in the development campaign. Amin formation is the target reservoir, at about 5,000 meters in depth, with some of the hardest rock formations in the area in excess of 50 Ksi compressive strength. The reservoir pressure gradient is approximately 18 kPa/m (1.84 SG) and static downhole temperature is around 178 °C. An integrated approach was taken to address the challenges as the field transitions from appraisal stage to development. This involved the selective deployment of technology along with improved operations, and implementation of several initiatives which resulted in a significant improvement in well durations and cost in excess of 40% within a year. The well design was altered from a five casing string design in the exploration and appraisal phase to a three string slim design with liner top completion. Additionally, a cemented completion design was introduced and executed successfully, involving the implementation of a specially designed degradable packer fluid to reduce the burst loads on the casing in the frac and production phase of the wells. The bit selection and drive type was changed from turbine drilling with an impreg bit to motor drilling with a PDC bit application specially designed for the field and its challenging conditions. The change led to major improvement in ROP (Rate of Penetration) and accordingly reduced time to drill the final 8 3/8" hole section. Furthermore, the implementation of Lean practices and following the well delivery process stages played a crucial role in aligning all parties involved together. A Performance Improvement Plan (PIP) was developed and implemented to capture the different initiatives in well design and operational excellence and was used as a vehicle for continuous improvement. The results show significant reduction in well cost and time by 40 % compared to well cost before implementing these changes. Recent wells have beaten the Best Composite Time (BCT) set in the field and reduced the overall duration from 260 days in the exploration stage to 55 days in the recent wells delivered in 2017. The cemented completion with degradable mud was a first time application in PDO, requiring in-house development and testing. The PDC bit used in recent wells was specifically designed for Khulud to replace the impreg bit and enhance ROP. |
| Databáze: |
OpenAIRE |
| Externí odkaz: |
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