Wintershall needed to enhance production in sour fractured carbonate reservoir

Conventional workovers or sidetracks in depleted wells are often not economically viable. In addition, killing a heavily depleted well can cause formation damage and decrease productivity. CT drilling techniques can significantly lower costs per drilled footage and enable the ability to work in a live well, which can make drilling in depleted wells economically attractive.

Real-time CT with turbine enabled improved drilling operation

The ACTive PTC live CT pressure, temperature, and casing collar locator tool and ACTive TC live CT tension and compression tool combined with the 2.125-in Neyrfor turbodrill and the 2.28-in Kinetic bit were run as part of the drilling BHA. Real-time downhole weight and torque monitoring was key to optimize drilling performance.

The 21/8-in-OD Neyrfor TTT turbodrill has an all-metal construction, providing efficient, high-speed drilling capability with greater durability to avoid additional trips out of hole. The turbodrill also drills a smooth borehole and less weight on the bit is required to drill, which ultimately increases drilling length before CT buckles.

Combined technologies improved production and cost efficiencies

The BHA helped Wintershall triple ROP compared with previous PDM drilling on CT. This technique reduced drilling time and costs, increased versatility toward drilling fluids, and enhanced reservoir knowledge through the use of distributed temperature sensing postdrilling.