Stabbing a TIW Valve

Stabbing a TIW Valve is an essential operation in well control during drilling, particularly during tripping operations. The TIW valve is a type of back-pressure valve used to provide a barrier against pressure from the wellbore.

Here’s a breakdown of the operation of stabbing a TIW valve:

  1. Purpose of the TIW Valve
    The TIW valve is installed to prevent backflow from the well when tripping out of the hole.
    It is especially critical in situations where the well may be under pressure and there’s a need to quickly isolate the wellbore.
  2. When and Where It’s Used
    Typically stabbed at the top of the drill string when pulling out of the hole.
    Most often installed in the kelly, top drive, or drill pipe during a tripping operation.
    Can be stabbed manually or using hydraulic systems depending on the rig setup.
  3. Stabbing Operation (Step-by-Step)
    a. Preparation
    Ensure the TIW valve is pressure tested and in good working condition.
    Make sure threads match the drill string connection.
    Have a safety plan in place; this is a high-risk operation if the well is under pressure.

b. Stabbing
Once a joint of drill pipe is pulled through the rotary table, pause before the pipe is laid down.
The TIW valve is stabbed into the open end of the pipe (or into a crossover sub if needed).
Quick and precise action is crucial to minimize the time the well is open to surface.

c. Make-up
The valve is hand-tightened initially, then torqued with tongs or a wrench to ensure a proper seal.
It should be installed so that it can hold pressure from below, acting as a check valve.

d. Pressure Check (if time allows)
In some situations, pressure test the connection after stabbing to confirm sealing.

  1. Post-Operation
    Once safe and secure, the pipe can be laid down or further operations continued.
    The TIW valve can be closed manually to shut off well pressure if needed.
  2. Safety Considerations
    Always wear appropriate PPE (face shield, gloves, FR clothing).
    Be aware of the risk of pressure release.
    The crew should be trained for fast and correct stabbing under pressure scenarios.