Well Isolation Tool

Circulating tool for annular isolation during displacement

Drilling valve

Protect the formation during displacement operations

The well isolation tool enables the operator to isolate the wellbore (below the tool's circulating ports) from hydrostatic and induced pressures and still circulate at increased rates. This is often done to control fluid loss to open perforations or an openhole interval below the tool.


With the well isolation tool, high circulation rates can be used to displace the upper part of a well without applying pressure to the lower part. It is most effective where there is no set-down point, such as a liner top for conventional weight-activated circulating tools. It is ideal where fluid loss to perforations or openhole sections would be expected below the tool, and it can be run above pressure-sensitive equipment such a fluid isolation valves.


  • Ball-drop activation and deactivation
  • Two internal ball seats that move to activate and deactivate the tool
  • Balls retained on seats in tool
  • Stabilizer and stabilizer-mill profiles to ensure there are no casing restrictions and to protect the diverter cup from possible damage
  • Availability in 7-, 9 5/8-, or 10 3/4-in sizes
  • No limit on rotation speed while circulating


  • Boosts annular velocity while protecting the formation and open perforations from excessive surge and equivalent circulating density (ECD) pressures
  • Prevents surging or swabbing the well during trips with built-in bypass channel around the annular-isolation diverter cup
  • Prevents losses under static and dynamic conditions
The Well Isolation Tool (WIT) is a circulating tool