BonnetBuster™
April 21, 2020
BonnetBuster™
An update for you all on our BonnetBuster™ service which we will do further tests on and release soon.
- Globally ‘well cost reduction’ and ‘tree wellhead repairs’ are key themes.
- Five valve bonnets are within the cylindrical recesses inside old Christmas tree blocks on the surface platform well in the upper image.
- “Failed valve” replacement needs a bonnet removal method delivering sufficient force to move it sideways, overcoming binding rust hidden by the grey paint.
- There is no conventional “flange gap”, for pushing the bonnet with specially shaped jacks.
- Moreover, pulling on the bonnet’s central thread (lower image) fails at typically 50 tonnes, using conventional techniques: up to 8 times less force than necessary.

Close up of bonnet threads that have been damaged from extraction attempt not utilising ThinJack Ltd.
- An alternative is replacement of the tree, with multi month manufacturing or re-machining times, unless new trees are “on the shelf”.
- Avoiding tree replacement, BonnetBuster removes threaded bonnets, shown with the upper image’s red wheel, and actuator bonnets, with the red cylinder. Specialist hydraulic power, from ThinJacks, draws rusty bolts through the bonnet’s bolt holes whilst moving the recessed valve cover outwards. Even separation avoids jamming.
- Controlled Force is delivered by this BonnetBuster service which is an order of magnitude more powerful than alternatives and saves days of service time.
- Raw human “power” and improvised tools are eliminated.
- ThinJack Ltd first developed and tested this new solution to access a 6 3/8″ 5M McEvoy gate valve using 180 tonnes of controlled force: nearly 4 times greater than alternatives.
- Further testing into 2022, aims at 400 tonnes, intending to remove the most stuck tree bonnets on surface platform wells.
- Easy replacement of the failed tree valve follows.
If you would like any more information on the system then please let us know and we would be delighted to help.