Overview
Objective
- Cut 9.625” 53.5# stuck Casing
Challenges
- Large casing size
- 26% Solid content inside well
- Limited tool availability. Main tools only in country
- High open flow area required for a stable RCT during the cutting operation
Solutions
- 2 x 2.937 PTC runs were proposed below the intended cutting depth achieving a total flow area 15 sq.in
- Rig circulation was completed after each puncher run until achieving clean returns
- RCT deployed managed to get the stuck casing immediately after firing, allowing the rig to continue operations
Results
- ZERO HSE Incident
- Clean cut of Casing was observed on surface
- Rig able to recover the requested casing in shorter time
Details
One of the major Oil & Gas operators in Middle East had a Land Rig stuck situation while running a 9.625” 53.5# casing. Client estimated that formation had collapsed around the casing and was not able to circulate.
There was a 7.25” restriction at the casing DV tool that prevented the RCT to cut deeper than 9345’. Hence the client decided to cut above.
As the required RCT was a large sized (7 in), with extensions, due to hydrostatic above 4,000 psi, it as necessary to punch enough holes below the cutting point. Allowing unrestricted flow below RCT is important to achieve a clean cut, in order to compensate the extreme upward forces developed by RCTs fired plasma.
Thus, as per Well information, WL team and Our Team, it was decided to punch 2 holes with 2.937” decentralized PTC so to achieve a flow area of approximately 4 sq.in, at 5ft and 10ft below the intended cutting depth.
Besides punching the holes, it was recommended to perform thorough circulation across the punched holes in order to clean any debris that could clog the holes before the RCT. Circulation was completed after each puncher run until obtaining clean returns at the shale shakers.
Finally, the 7.000 RCT was deployed with rigid overbody centralizers and the result was satisfactory for our client that immediately lost the applied overpull once the cut was done. With no HSE Incidents, a clean cut of 9.625 Casing was observed on surface. Eventually, Our Client was able to resume their program without the use of explosives or other more time consuming and expensive options.
