Case Study: North Sea Operating Company saves 7.5 rig days and $1 million with SLB's ProMILL P&A system

ProMILL trip-saving milling and underreaming system helps save operator 7.5 rig days and USD 1 million as part of an ongoing abandonment operation

SLB worked with North Sea Operating Company on a North Sea P&A operation that required efficiently section milling two windows of more than 100 ft in 13⅜-in casing and underreaming the open hole in a single trip so an abandonment cement plug could be placed. The company needed to reduce cost and regulatory risk while improving milling efficiency, and SLB proposed the ProMILL trip-saving milling and underreaming system with the WavEdge ridged milling element.

SLB implemented an integrated solution using ProMILL together with the WELL COMMANDER ball-activated drilling circulating valve to improve cuttings removal and eliminate a separate conditioning trip. The operator milled and underreamed 109 ft and 100 ft sections in single runs, achieved an ROP of 4.2 ft/h versus a field average of 3 ft/h, and cut the overall P&A operation by 7.5 rig days and USD 1 million.