Removal of Damaged Pipes with Worn Ends During Major Repairs of Oil and Gas Wells

The relevance is determined by the need to solve a number of scientific, practical, and engineering problems related to fishing operations during well workovers. The article provides information on some cases where it is necessary to repeat the operation after completing the fishing work, which should be performed with the lowest possible force parameters and process adjustments. As a result of non-compliance with these requirements, as well as defects formed in the lifting pipes (holes, cracks, wall thickness reduction) due to long-term well operation, the use of standard pipe catchers during emergency operations is further increased. Frequently encountered deformed emergency ends of complex configuration are classified. A classic method for correcting deformed ends is noted, consisting of milling with bottomhole and ring milling cutters and other auxiliary catchers, which can complicate the well situation. The aim of the work is to improve the quality of fishing operations, speed up the extraction of emergency lift pipes with deformed ends of complex configuration, and prevent complications during their extraction from the well. This goal is achieved by implementing an innovative, improved method and design of standard fishing tools adapted to well conditions. The use of the developed straightening and fishing tool—a combined bell consisting of a through bell located at the bottom, which does not function as intended but bends, crushes, and collects the deformed ends in the center, achieving a cylindrical shape and deepening the end of the pipe inward, and a bell located at the top—allows for the removal of the pipe in a single operation by cutting the thread and then screwing onto it. The use of this tool eliminates multi-step operations to correct deformed ends. Depending on the internal diameter of the column and the type and size of the pipes to be extracted, as well as the clamped and sequentially extracted emergency pipes of the first and second rows of lifts with normal emergency ends, by changing the component elements and installing the required number, it is possible to reliably grip and extract them from the well.