Open hole logging in fragile conditions
The operator intended running a borehole imaging tool and mechanical caliper through this section in OH. This was also run through the expanded ESS for depth correlation and positioning purpose.
They approached Welltec® for a solution that could convey the logging tool to the bottom of the well while ensuring the integrity of the OH wellbore wall.
Welltec came up with a mathematical model for co-relating internal working pressures of the Well Tractor® to the amount of pressure exerted on the wellbore wall by a Well Tractor wheel of a given diameter. This allowed the operator to predict the depth of penetration of the Well Tractor wheel into a formation of a given compression strength.
The borehole imaging log was run in OH before the ESS was deployed in order to gauge the cross-sectional shape of the borehole. The borehole imaging log was then to be run again once the ESS was installed and expanded in order to investigate the screens’ conformance with the borehole wall.
• All six runs were performed in less than 70 hours.
• Operator received accurate placement of the completion based on wireline depth measurement as opposed to pipe measurement.
• Cost savings estimated at approx. USD 6 million in rig-time saving alone.
The Well Tractor was regarded as a revolution in the industry when it was introduced in the 1990’s. It enables operators to extend the reach of traditional e-line deployment into highly deviated and horizontal wells.