By Mike Killalea, Editor and Publisher
A three-year MPD drilling campaign in a high-pressure formation by Saudi Aramco realized a host of benefits, compared with conventional methods, according to a paper presented at the 2015 IADC/SPE Managed Pressure Drilling and Underbalanced Operations Conference, held in Dubai during April. “By using MPD, we were able to avoid influxes, mud losses and hole stability issues by maintaining a constant bottomhole pressure,” said co-author Abdulaziz Mutawa, Workover Engineer for Saudi Aramco. The wells were drilled in the Kingdom’s Campaign Field.
Key improvements reported on the 11-well drilling campaign during 2012-2014 included:
- 25% increase in ROP;
- Virtual elimination of stuck pipe nonproductive time and lost circulation;
- Enhanced formation evaluation;
- Enhanced formation integrity, due to lower mud weights with lower solids content;
- 50% cost reduction on drilling fluids; and
- 23% improvement in rig time.
The paper was a regional example of onshore MPD in the Middle East, where knowledgeable observers indicate that the technology is far from commonly used. The project’s success could well pave the way for more MPD projects in Saudi Arabia, Mr Mutawa said.
“Utilizing the MPD system was a step-change in building water injection wells in the Campaign Field,” he noted. “The successful implementation of MPD has been considered as the first stepping stone for MPD in Saudi Arabia.”
Elimination of stuck pipe through MPD was a highlight of the project. The team encountered stuck-pipe problems on the first MPD well but tried to resolve the problem conventionally. “We spent a lot of time trying to free the pipe in the conventional way, and it was not successful,” Mr Mutawa said. By reverting to MPD methods, the problem was resolved with only four hours of NPT. The next six MPD wells experienced zero stuck-pipe NPT. In comparison, Mr Mutawa’s data revealed, an average of 151 NPT hours were lost due to stuck pipe on seven previous conventionally drilled wells. One well suffered 615 hours of stuck-pipe downtime.
The paper, IADC/SPE 173818, “The Successful Application of MPD Technology in Drilling Horizontal Wells in a High Pressure Formation Heterogeneity to Mitigate Drilling Hazards,” was co-authored by Mr Mutawa with Nelson Pinero Zambrano and Riyadh Bargawi, Saudi Aramco; Ayoub Hadj-Moussa, Cherif Mazouz, Paco Vieira, and Ramon Zambrano, Weatherford.