Drilling applications expand snubbing unit use

Snubdrilling with variations of proven hydraulic workover unit technology provides several advantages over conventional and coiled tubing drilling for special cases. For several decades, snubbing has been used to drill cement, packers, shale, barium sulfate, and other wellbore obstructions in live and dead wells. Recently, a snubbing jack was used to drill a 5,165-ft well in South America. And the oil industry is showing a tremendous interest for snub-drilling. This article describes how this new application compares to conventional and coiled tubing drilling. The recent high-pressure snubdrill operation in Venezuela is reviewed.