Coiled tubing drilling remains one of the fastest growing technologies in the drilling industry. As of year-end 1996 approximately 60 horizontal underbalanced wells have been drilled in Western Canada with coiled tubing. The benefits of this technology are intuitive, however there have been few opportunities to make direct comparisons to adjacent horizontal wells drilled with conventional techniques.
In 1996, Crestar Energy Inc. contracted Canadian Fracmaster Ltd. to drill 5 horizontal underbalanced wells in Southeast Alberta. The drilling of these wells provided opportunity for project analysis of operational factors and costs. This paper presents the results of the five wells drilled, analyzes time breakdowns for key operational steps. Cost comparisons of these wells with similar conventional overbalanced wells and initial reservoir productivity will also be assessed.