Abrado’s Operations Excellence program is a structured approach including detailed pre-operations planning and well engineering, while incorporating drilling optimization methodologies and real-time data analysis while milling. In 13.3/8″ casing, the 7‐3/4” Medusa™ milled 42’ up with 33% wear and down 15’ showing 5% wear.

CHALLENGES

Major Operator seeking to improve section milling ROP and operational efficiency on a multi-well P&A project. The Well Plan requires two barrier zones comprised of an inner window in 9-5/8” casing, an outer window in 13-3/8” casing, and all encapsulated by the 18-5/8” casing. Scrub the 18-5/8” casing ID to prep for inflatable packer and cement plug installation. Maintain maximum ROP while mitigating swarf build up along with consistent WOB while milling down and consistent Overpull while milling up. Operate tool within performance specifications in order to achieve optimal results while decreasing non-milling time.

SOLUTION

Maximized ROP while performing inner section in 9-5/8” casing by continuing to mill ahead with 7-3/4” CSM (Conventional Section Mill) after verifying cut out. Focused on monitoring surface data trends, rather than specific values in order to maintain optimal milling performance and minimal cutter wear. Utilized a pre-planned bi-directional milling strategy for the 7-3/4” Medusa™ in the 13-3/8” casing with the goal of maximizing time spent milling and minimizing time spent hole cleaning.

RESULTS

• A project first 9-5/8” inner casing section window utilizing a single cut out BHA and a single mill ahead BHA to deliver 70’ section window.
• Completed 13-3/8” outer casing section window utilizing a single cut out BHA and a single mill ahead BHA to deliver 57’ section window.
• Most efficient 9-5/8” x 13-3/8” dual string casing sections executed on the project.
• Validated tool reliability while operating in an increased performance range.
• Single trip efficiency gains decreased total rig time and improved inventory utilization.