Schlumberger announced recently it had invented a comprehensive single-trip and abandonment system which enables an operator to save significant dollars in its abandonment milling, cutting, and retrieving operating costs. It also cuts the required trips by about 50 per cent and reduces the number of days required for plugging-and-abandonment (P&A) operations.
This “all-inclusive system” is composed of three internal systems:
- ProMILL trip-saving milling and under-reaming system – where conventional milling and under-reaming systems take four days to finish the job, this process combines a bridge plug assembly, a section mill, and a high-ratio under-reamer for a single-trip solution, achieving rock-to-rock zonal isolation and preparing the foundation for an abandonment cement barrier. The company claims it “eradicates all potential leak paths (including channeling, micro-annuli, and mudcake) from the abandonment barrier, creating a smoother wellbore that is fit for cementing.”
- ProCISE casing cutting and recovery system – designed to sever a single string of casing and engage it for removal in one operation. It uses an in-line casing spear to grab the casing and uses overpull to hold it for cutting. The company says “this new technology has three sets of blades that can perform multiple casing cuts during a single run.”
- ProLATCH wellhead retrieval system — handles any combination of casing and wellhead types using wellhead retrieval systems and multi-string pipe cutters. The company says, “It combines a high-performance wellhead spear, hydraulic pipe cutter, and non-rotating stabilizers to recover surface case and subsea wellheads for plug-and-abandonment operations.”
When tested, Schlumberger claims it is a success story. The real-world challenge was to reduce rig time required to cut, pull, and circulate around 24.4475 cm casing known to have annular solids and gas on a deepwater slot recovery operation. The result was the crew retrieved the wellhead seals on the bottom hole assembly (BHA) in one trip. They cut the casing free and circulated out the trapped gas and packed annular solids in a single trip with established well control. The traditional method would have needed at least three trips.
#Schlumberger #ProMILL #ProCISE #ProLATCH #milling #cutting #wellheads #deepwater #gas
