The job consisted of two drilling runs to allow for an interim inspection of the centralizers and BHA. Half the centralizers were placed near the BHA to expose them to both the formation and the rigorous drilling conditions. The other half were placed at the top of the liner to remain inside the cased hole. This approach was decided because it meant the upper centralizers never went out into the open hole, while the bottom five were exposed to formations while drilling.
The liner was run to depth and used to drill at a penetration rate of 75-100ft/hr, with surface rotation speeds of up to 90RPM.
After drilling, a total of 1,500ft of the liner returned to the surface for inspection. The centralizers remained in their original location and rotated freely without any issues. No damage or appreciable wear was found on the centralizers. No difference was found in wear between the ones exposed to the formation and those on the top.
In total, the project lasted 54,6 circulation hours.
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