A recently developed electromechanical precision pipe-cutting tool is being field tested. Its primary applications are to cut and free stuck pipe (tubing or drillpipe) or cut pipe to modify a production completion installation. Cutting pipe in today's complex completions presents many challenges. Testing of this new cutting technology has demonstrated significant advantages over previously used equipment. It is non-ballistic, has a large cutting range for a wide range of metal pipes, provides cut monitoring and success detection. The precision of the cut is facilitated by the tool's internal programming (smart function) which allows for specifying the type of metal to be cut, monitoring the depth of the cut, recognizing the drag and making the appropriate adjustments to complete a cut. The ability to complete multiple precise cuts reduces associated rig time. Its large operating temperature and pressure ratings (20,000 psi), large cutting size range, and portability make possible quick deployment to offshore and land operations. Additional field-demonstrated capabilities include: performs accurate smooth cuts, cuts harder metals with a high chrome content, performs precision cuts for inner pipe cutting, works at any deviation, produces minimum debris, surface system allows application to any wireline, does not require circulation holes for the cutting device, operation deployment is not constrained by chemical issues relate to safety and environment, the cutter's light weight, short shipping length (two sections, each less than 10 feet in length), and compatible portable support equipment allow for quick deployment in a variety of transport modes. This paper includes a case study to illustrate the operating challenges associated with tubing and drillpipe cutting in a variety of conditions and environments.
The industry has traditionally utilized explosives (De Frank 1–2, Nimmo3) and chemical cutters (Cole4) as a solution to recover pipe and to free drilling pipes. Later on, jet and Radial Cutting Torch (RCT) cutters (Jurgens 5) were also employed in these applications. These methods have performance and operational issues (Jurgens 5) associated with their design concepts. Well scenarios with a more difficult reach utilized coil tubing (Blount 6) to deliver other cutting methods and solutions (Fanguy 7, Loving 8, Hebert 13). A number of tools have been developed offering cutting solutions to the industry (Hailey 9, Flanders 10, Mason 11, Campbell 12, Portman 13). The need to modify the configuration of a production string introduced the demand for cutting solutions to allow packer retrieval (Triolo 14). The production packer retrieval method can involve the cutting of an inner jacket to release the packer assembly. String geometry cross-section constraints can result in a very small wall-to-wall separation which requires a precisely controlled pipe-cutting procedure. In more complex and expensive installations the precise cut must also ensure that lines and other parts adjacent to the pipe structure being cut are not damaged. Another challenge introduced to pipe-cutting operations is the deployment of installations with exotic and specialty metals made with high chome and nickel content (Portman 15). Over the years the industry requirements for pipe-cutting operations has evolved and become more stringent in the areas of health, environment, safety, ease-of-transport deployment and storage, cut precision and controlled, metals with a wider variety of metal composition, strength and corrosion specs.