Application of a Light Rig in Deep Exploration Drilling Operations in Nigeria

摘要

The upsurge in drilling activities in 2004, occasioned by thestrong oil prices resulted in a challenging rig market situationsuch that operators have to plan well in advance to be able toget a rig for the next well campaign. For desperate operators,the only option is innovation or new technology and unusualrisk taking.An operator in Nigeria recently adapted a light work overrig of 800 horsepower and 320,000lbs pulling capacity to drillan exploration to 11,000 ft. This was operating the rig atbeyond its capacity.Minor modifications were made to the rig to enable therunning of casing strings, and operations monitored with thehelp of wells software, resulting in the successful drilling andabandonment of the A-1x well. The result was a 30% savingsof the budget well cost contributed mainly from the slimmerdesign and lower rig rates of the light 800 hp rig. It is alsonoted that the light rig was moved in 8 days compared to 23days planned with the heavier rig.The paper highlights the detailed planning and executionof the drilling phase of the A-1x well and how the capacityissues were addressed leading to the estimated savings of$2million.