Coretrax currently provide a one-trip system to allow inflow testing operations to be completed in the same run as the wellbore clean up. During a long-standing wellbore clean up contract in the Middle East, Coretrax identified an opportunity to deliver further rig time savings to the client by combining the cement drill out run with these clean up/inflow test runs – eliminating an additional trip in hole.
The cement drill out operations involve drilling out cement, landing collars and float collars before conducting inflow testing operations and therefore a number of new challenges are introduced including long drilling hours and circulating debris past the packer element. The existing CX-LTTT was a proven and robust inflow test packer capable of combining the clean-up, displacement and inflow test operations in the same run, however the introduction of these new challenges required a heavy-duty solution to be developed. Coretrax in-house Engineering and Design team conducted extensive R&D and in just under 3 months, the CX-LTTT(HD) was launched to market.
The CX-LTTT (HD) has since gained a substantial run history of its own and when used in these operations delivers an average of 30 hours rig time saving. The tool is designed with a large concentric bypass that allows for quick running speeds and a generous flow area around the tool to achieve high flow rates, which is essential for recovering the debris out of hole and minimizing the risk of damage to the packer. Furthermore, the packer is designed with customisable shear value to ensure that it is suited to a range of applications.
Key Advantages
- Robust design
- Customizable shear value
- Torque through capabilities
- Simple set and release procedure
- Large bypass area
In Q2 2017, the CX-LTTT (HD) was run for cement drill out operations and in flow testing of a 7” 32# liner. The cement was tagged at 11,905ft MD and drilled out along with the landing collar and float collar to a depth of 12,291ft MD – a total of 386ft was drilled over a period of 12 hours. The hole was circulated clean before landing on the 7” TOL at 11,490ft and setting down 35,200lbs to shear the CX-LTTT (HD) and function the tool, a backside pressure test of 1,000psi over 10 minutes was achieved confirming the integrity of the CX-LTTT (HD). The packer was unset and fresh water was pumped to achieve a final drawdown pressure of 4,400psi. The CX-LTTT (HD) was set by setting down 30,000lbs and the pressure bled off in stages of 500psi to perform the inflow test, plotting on a Horner Graph as per the client’s procedures. Once the test was confirmed as successful the drill string was pressured to 4,200psi and the CX-LTTT (HD) unset and POOH.
Job Highlights;
- Cement Drilled: 386ft + landing collar and float collar
- Total Drill Out Time: 12 Hours
- Time Saving to Customer: 33 hours