Continuing improvements enhance CT reliability and applications

PRAMOD KULKARNI, Editor

World Oil is pleased to present the 2013 edition of its annual coiled tubing (CT) supplement. Since their introduction to the oil and gas industry in the 1960s, CT applications have increased over the decades through improvements in tubing metallurgy, advances in rig designs and the development of small-bore downhole tools, such as rib-steered drilling motors.  CT is now a cost-effective intervention tool with multifaceted re-entry drilling, completion and production stimulation capabilities, with new applications emerging for formation evaluation, shale fracturing, fishing, and even plugging and abandonment, both onshore and offshore.

Routine CT use for intervention depths beyond 20,000 ft, and even as deep as 35,000 ft, is made possible through metallurgical improvements by tubing manufacturers to strengthen mechanical properties of the tubing, and achieve better fatigue performance in the tube body and the bias weld. To ensure reliability, computer modeling can be used for fatigue testing under simulated field conditions. Tubing made out of corrosion-resistant alloys is available for extreme CT operations in downhole formation fluids that have a high water cut or corrosive CO2/H2S content. 

TeleCoil intelligent CT service provides real-time downhole monitoring of depth correlation, differential pressure and temperature. Photo courtesy of Baker Hughes.