Drilling and producing in high latitude environments is unforgiving. Temperatures often drop below –20°C and can reach as low as –50°C. Isolated locations or vast distances, extreme weather conditions and periods of deep darkness can restrict transportation of personnel and equipment. As a result, job complexity often leads to outright failure or an exponential increase in time to accomplish what would be a routine task in a normal environment. Often the best route to success and efficiency in these conditions is proven technologies and strategies. For over 80 years, e-line conveyance and tools have been refined and improved to become a very reliable means of data gathering and workovers, such as plug setting, debris removal, hardware milling, pipe recovery and so forth.
Modern electric line (e-line) capabilities can now accomplish what conventionally would have been rig- or coiled tubing-based
workovers. In the North Sea, Canada, Alaska and Russia operators use e-line to perform ‘heavy’ workovers; explosion-free cutting of tubulars, scale and debris removal, milling through hardware such as nipples, failed isolation valves and flapper valves, and replacement of hardware, such as gas lift valves and Electric Submersible Pumps (ESP’s) in extended reach horizontals.
This paper discusses the benefits e-line tools can bring to accomplish ‘heavy’ workovers in a reliable manner in high latitude environments. Several case studies are presented to demonstrate these applications in practice.