SHARC PDC Exceeds Qatar’s North Field Single Day Drilling Record by 38%

Published: 04/01/2012

Blue hero texture

Specialized PDC to endure highly interbedded formations required

An operator drilling 12 1/4-in, 55° to 60° tangent sections in Qatar's North field was regularly experiencing severe impact damage to PDC cutters resulting in reduced bit life. Section drilling to TD normally began in the Hith formation and transitions to the Khail formation. Lithology predominantly consists of carbonates—anhydrites, dolomites, and limestones that are highly interbedded and have an unconfined compressive strength of 9,000 to 30,000 psi.

The operator wanted to improve ROP by stabilizing the PDC, reduce microballing, and drill the greater-than 6,000 ft 12 1/4-in section to TD in one bit, with a daily footage of over 2,000 ft.

To increase drilling performance for the operator, a new bit was designed, and surface drilling parameters as they relate to the drilling assembly were analyzed. The engineering team used several design and simulation tools in their bit redesign:

IDEAS dynamic engineering system

With the IDEAS platform, designers observed how a bit would interact with different formations from Hith to Khail. They analyzed the results and made iterative design changes to rapidly advance an engineering concept to a field-proven PDC design.

Images - The SHARC 12 ¼-in MSi716LEBPX PDC with ONYX cutters and PDM powered RSS directionally drilled 3,100 ft in one day.
The SHARC 12 1/4-in MSi716LEBPX PDC with ONYX cutters and PDM-powered RSS directionally drilled 3,100 ft in one day.
Graph - New North Field average footage per day benchmark for entire 12 ¼-in directional section.
New North field average footage per day benchmark for entire 12 1/4-in directional section.

DBOS system analysis

DBOS drillbit optimization system uses offset well data to choose a fixed or roller cone bit with the appropriate combination of cutting structure, gauge protection, hydraulic configuration, and other critical characteristics. This capability enabled the bit redesign team to identify the best drill bit for the operator's interval drilling.

Further bit development included sensitivity analysis with the PowerDrive Xceed rotary steerable system for harsh, rugged environments powered by a PowerDrive vorteX powered rotary steerable system to determine the optimal operating parameters. The results from the design and simulation analysis led the engineering team to recommend the 12 1/4-in SHARC high-abrasion-resistance PDC drill bit with ONYX PDC cutters to provide maximum durability.

New drillbit design significantly improved drilling performance

The newly designed BHA directionally drilled the 6,001-ft 12 1/4-in section with a field record ROP of 139.4 ft/h. The daily footage average on the run was 2,572 ft, setting a new record and beating the old record by 38%. A 24-h footage record was set as well at 3,100 ft, 29% over the previous record.

Location
Qatar, Asia, Onshore
Details

Challenge: ROP improvement with a stable PDC design, reduce microballing, and drill the 12 1/4-in section of more than 6,000 ft in one run, with a daily footage of over 2,000 ft.

Solution: Use IDEAS platform to design a new SHARC impact and abrasion resistant PDC bit with ONYX cutters, and use more effective surface parameters to maximize bit life.

Results:

  • Directionally drilled 6,001 ft, setting a field record ROP of 139.4 ft/h.
  • Set a 24-h footage record of 3,100 ft, 29% over the previous record.
  • Drilled a daily footage average of 2,572 ft, 38% over the previous record.