Using three reamers on a single BHA saves operator 16 hours

Using three Rhino™ integrated borehole enlargement system reamers on one BHA, a major operator successfully drilled and reamed the 18.125‑in × 22‑in hole from 1,707 m to planned section total depth of 2,718 m. This saved the customer 16 hours of rig time while significantly reducing costs.

At a deepwater well located offshore South America, a major operator planned to run an 18‑in liner through a 22‑in casing. However, the cement sheath was left after the 18.125-in bit was drilled, and the resulting tolerance presented a concern with running the liner. This hadn’t been done in the location before and similar applications required a dedicated run to clean cement prior to running the drilling BHA. As a result, the objective was to use a single BHA for multiple operations to efficiently complete the task while saving time and costs.

Three Rhino integrated borehole enlargement system products from SLB were used on a single BHA to maximize performance and efficiency. The top reamer was the Rhino hydraulic underreamer with cement cleanout blocks. The middle reamer was also the Rhino hydraulic underreamer but fitted with Predator™ cutter blocks. The bottom reamer was the Rhino multicycle hydraulic underreamer, which performed rathole elimination. Cement cleanout blocks cleaned out the cement inside casing while Predator cutter blocks did the enlarging.

By using a single BHA, drill time was reduced, saving the operator 16 hours of rig time and significant costs. This also ensured that handling and making up the BHA would be done only once, reducing employees exposed to risk, as a second BHA would not have to be handled.