Foster Clamp for BOP Flange Alignment


  • Allows for pre-alignment of exposed studs.*

  • Easily aligns and removes BOP stack connections while enabling the rotation of the BOP stack during alignment and removal processes.*

  • Fine-tunes ring gasket location.*

  • Works for both vertical and slant rig operations.

  • What once took hours can now be completed in just minutes.

*All while keeping hands away from pinch point areas.


  • A 2 piece circular ring that quickly attaches around either the casing spool or BOP flange.

  • 4 L-shaped clamping member blocks with 2 adjustable jacking screws per clamping member which allow for up to 4.5” of misalignment.

  • Spherical bearing at the end of each jacking screw to allow for rotational, vertical, and horizontal movement of the opposing flange for precise alignment of stud hole locations.

  • 15,000psi or 7.5 tons of pushing force per clamping member.

  • 10 threaded mounting locations for clamping members per ring.

  • Single 1-5/8” socket size for all bolt connections.

  • Lanyard tie-off on each clamping member.

  • Unlimited ring diameter sizes available. 

  • No pieces to come apart to drop down the drilling hole.

Patented and multiple patents pending.