CD drilling is a proved method of drilling vertical and directional wells. CT string with PDM is used instead of traditional compound tubing. Either under- or overbalanced drilling can be performed.
“Intellectual” BH assembly and telemetric data acquisition allow the operator to define the direction for moving a drill bit.
In comparison with the traditional drilling, CT drilling is more economically efficient way of well drilling.
Benefits of CT drilling
- No joints, shorter duration of round trips, fast rig up/down.
- Continuous circulation during RIH and POOH/round trips.
- Ability of easy under- or overbalanced drilling.
- High rate of building up a drift angle – up to 10 degrees per 10 meters.
- Small OD of the string and BHA is ideal for recurrent entering the well for cutting side windows in casing strings.
- “Intellect” automatically controlled BHA and monitoring of the BH parameters in real time.
- Less surface area required, less expenses for drill plot preparation.
- Less personnel, lower HSE risks.
- Closed operations cycle – less environmental impact.