Rotational ball seat

Reduce operating time and risk

The rotational ball seat (RBS) is run as part of the setting string for any conventional hydraulic-set liner hanger system, whether cemented or uncemented. When pressure is required to set the liner hanger, a ball is dropped from surface and lands on the RBS, blocking the tubing; subsequently, pressure in the string above the ball can be increased. Provided the pressure remains below the predetermined shear value, multiple pressure-actuated tasks can be performed, including setting the liner hanger slips, verifying their engagement with the previous casing string, releasing hydraulically actuated tools such as the collet running tool (CRT), and operating additional completion tools in the string.

Increasing the pressure above a predetermined value causes the RBS to shear and rotate, and pushes the ball down. Fullbore ID is restored, enabling normal cementing operations, including the passage of drillpipe wiper plugs. Because the RBS is run in the setting string and energy dissipates while propagating downhole, when the seat shears the formation experiences a lower pressure surge compared with a conventional ball seat located at the liner toe.

Designed to function within a predetermined pressure range, the RBS can also be used in applications that require two independent ball seats.