What do you do when you run into a casing connection that is impossible to break out? Do you send a man into the red zone with a reciprocator saw while the string is in the elevator? Or are you willing to spend some time rigging up a belt tong to assist where your roughneck or casing tongs were not able to deliver the required torque?
Hopefully not. We have safer and more efficient ways of handling P&A jobs with obstinate connections.
What's the problem?
There are several different reasons for a connection being too hard to break out. Sometimes we face connections that are older than the operators trying to break them out. But even experienced crews have a hard time fighting these obstacles:
- Threads from an earlier era that requires high break-out torque.
- Well conditions that may lead to corrosion:
- High pressure
- Restrictions in the hole; you need to work through tight spots, and the connections get over torqued due to the rotation of the string.
- Cold-welded threads. Friction between threads during make-up has made the threads freeze.
- Lock tight threads: Threads glued together on connections once considered to be permanent.
- Collapsed pipe being oval due to high pressure in the well
> Read also: Casing make-up torque and turn
Cut the darn thing
If you can't break out the connection when trying to pull the casing, use a Cold Cutter. It's a basic off-the-shelf saw wich is pre-installed in the scissor table between the back-up and the make-up tongs. There it is - ready for use when needed. However, most keep it it up the sleeve and rig it up only when they need it, as it takes only around 10 minutes to make it operational. It runs on the same hydraulics as the tongs and only needs additional water for cooling. The speed is adjustable to fit the hardness of the steel you're about to cut, and the blade is easy to change.
Compared to the traditional solutions, the Cold Cutter improves the process of cutting casing:
- It's right at your hands. You don't have to remove your tongs to rig up the saw.
- No extra personnel needed.
- Remote operated. No people in red zone.
- The Cold Cutter comply with the rules for hot work in Zone 1.
The Cold Cutter is basically a casing tool made for P&A applications. However, the saw cuts drill pipe as well, and OWS have used it on several projects where difficult formations and tight spots threaten, and over torqued drill pipe is a regular problem.