Pump Open Sub

When deployed as part of a downhole plug assembly, the Pump Open Sub is primarily designed to act as a single barrier against wellbore contents.

The Pump Open Sub plunger is secured in place with a series of shear screws which are designed to shear out when a predetermined pressure is applied from above the Pump Open Sub.

Once the plunger is sheared out, there is a clear flow path through the Pump Open Sub. This allows for full equalization across the barrier device, circulation, communication to prevent recovery of “wet” tubing strings or production of wellbore contents.


When deployed as part of a downhole plug assembly, the Pump Open Sub can be:

  • Used as a barrier to allow setting of hydraulically-set packers having to make an equalizing run prior to plug recovery
  • Remotely “opened” by pressuring the tubing above to the pre-set shear rating - the well can then be brought back online without any intervention
  • Used for creating tubing overbalance prior to fracture stimulation operations
  • Deployed as a contingent equalizing device in high debris environments
  • Used as a mechanical barrier during wellhead removal/tree valve maintenance

Features & Benefits

  • Can be retrofitted to suit existing lock mandrel/equalizing assemblies

  • Multiple setting values (500-psi minimum - 5,000-psi maximum) in 500-psi increments
  • Large flow area after pump out in flow type/circulating applications
  • Sheared plunger retained within the sump of Pump Open Sub eliminating unnecessary well debris
  • Minimizing wireline runs
  • Can be sheared out even if debris restricts access to primary equalizing facility by applying sufficient pressure

Product Code: 300