During the exploration and appraisal phase in the RJ-ON-90/1 block, operated by Cairn Energy India in the Thar Desert of Rajasthan, India, the company discovered numerous oil fields in the Barmer Basin spread over a huge area. The emphasis was to develop these fields with significant savings in both land and infrastructure costs while minimizing environmental impacts. A compact rig design coupled with a multi-well pad concept was the chosen solution.

The paper presents use of an innovative onshore pad drilling system which was implemented via a custom built Rapid Rig technology that allows fast, efficient drilling operations on multi-slot pads to enhance the success of the extensive drilling campaign for these oilfields.

The rigs are highly mobile, skid mounted, electrically driven 1,000HP "Super singles". They were custom built in Houston for Cairn to deploy in Rajasthan for the drilling of more than 350 development wells. The Rapid Rig's small footprint and self deploying design allows for ease of transport and faster onsite rig-up. These rigs are the first of their kind with wheels attached to the base structure. Unlike conventional rigs, these purpose-built rigs move easily and quickly (4hrs) between pad slots without rigging down, which in turn cuts well construction time and delivers greater efficiency at reduced costs. The fully automated rig floor coupled with an innovative pipe handling system reduces crew size and accident exposure (zero pipe handling LTI's) while providing a more comfortable and efficient work environment, leading to a substantial reduction in well construction time (1,2001,500m wells are drilled in 7 to 9 days).

The paper will explain detailed aspects of the custom made Rapid Rig design and its implementation including the pad drilling concept. It will also demonstrate how this significantly improved the well delivery, contributing to substantial cost and well construction savings without compromising HSE standards.

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