coiled tubing drilling

COILED TUBING DRILLING Abhijeet Narang, Shiwangi Bhardwaj University of Petroleum & Energy Studies, Dehradun. In drilling industry, a tubing is a tubular having diameter between 1” to 3.5” in diameter. Since the diameter is so less, the flexibility is an obvious quality of the string. This quality has made it adaptable to the field of drilling technology as it is easy to transport as it comes on a spool. This wounding ability allows it to be manufactured in form of continuous tube instead of joints. So, it can be forced down through the stripper installed on the injector. Thus, maintaining a hydraulic seal around the well which remains missing in case of normal drill pipe. In the coiled tubing drilling the drilling is carried out with the help of a mud motor. The tubing is kept straight during drilling by selecting appropriate weight on bit. It allows drilling a consistent small diameter wellbore which is particularly helpful in formations like shale. Apart from above advantages it also encourages one new technology in the field, under-balanced drilling. This ability is provided by the fact that coiled tubing allows to work while flowing produced fluids and also continuously pumping while tripping in and out of the hole, which in turn minimise the formation damage by reducing fluid penetration. The technology is very fascinating, but has certain obstacles in its route. The main problem is its inability to rotate. This fact reduces the life and reach of the coiled tubing. Also the logistics cost increase by a factor since the specialized equipment are required. But, despite certain limitations this technology has got all the potential to develop. A possible solution to problem is providing a connection in the coiled tubing after a certain length. This will increase its reach and certain rotation ability.

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COILED TUBING DRILLING

Abhijeet Narang, Shiwangi Bhardwaj

University of Petroleum & Energy Studies,

Dehradun.

In drilling industry, a tubing is a tubular having diameter between 1 to 3.5 in diameter. Since the diameter is so less, the flexibility is an obvious quality of the string. This quality has made it adaptable to the field of drilling technology as it is easy to transport as it comes on a spool. This wounding ability allows it to be manufactured in form of continuous tube instead of joints. So, it can be forced down through the stripper installed on the injector. Thus, maintaining a hydraulic seal around the well which remains missing in case of normal drill pipe. In the coiled tubing drilling the drilling is carried out with the help of a mud motor. The tubing is kept straight during drilling by selecting appropriate weight on bit. It allows drilling a consistent small diameter wellbore which is particularly helpful in formations like shale.

Apart from above advantages it also encourages one new technology in the field, under-balanced drilling. This ability is provided by the fact that coiled tubing allows to work while flowing produced fluids and also continuously pumping while tripping in and out of the hole, which in turn minimise the formation damage by reducing fluid penetration.

The technology is very fascinating, but has certain obstacles in its route. The main problem is its inability to rotate. This fact reduces the life and reach of the coiled tubing. Also the logistics cost increase by a factor since the specialized equipment are required.

But, despite certain limitations this technology has got all the potential to develop. A possible solution to problem is providing a connection in the coiled tubing after a certain length. This will increase its reach and certain rotation ability.