Use of Drilling With Casing Technology to Provide Operational Efficiency in the Vienna Basin

Drilling with Casing (DwC) technology is an efficient well construction process in which the wellbore is simultaneously cased while being drilled, enabling cementing operations to occur almost immediately after the casing is drilled to its planned setting depth. This technology is proven to mitigate drilling hazards such as lost circulation and wellbore instability as the hazard interval can be isolated in a single trip, reducing or eliminating problematic surge and swab effects seen with conventional drilling methods. An operator in the Vienna Basin is currently increasing operational efficiency saving up to two days per well by implementing DwC methods in the surface intervals in the wells’ basis of design. Using this technology, they have been able to drill 1–2 more wells in the allotted time frame enabling earlier recovery of oil and gas versus using conventional drilling methods. Formation drillability analysis concluded the 470m +/- siltstone, sandstone and clay surface interval could be drilled in a single pass with a 13–3/8-in. × 16-in drillable DwC bit. A fully integrated top drive casing running and drilling system compatible with the drilling rig was used to drive the casing. After cementing, the 13–3/8-in casing shoe track and DwC casin bit were drilled out with a conventional PDC or tri-cone bit, eliminating a dedicated drill out trip. The wells portrayed in this paper used DwC in the surface intervals, allowing the operator to reach the intended surface casing depth requirement. The equipment selection, operation, results, and conclusions will be presented.