The variety of accidents which happen during the construction of oil and gas wells causes the expansion in the use of magnetic fishing tools. However, the known tools based on permanent magnets have a significant drawback involving the flat working surface of the magnetic system that does not permit to achieve a considerable attraction force to a fished object of complex geometric shape. Therefore, the aim of the research is to increase the efficiency of removal the objects of irregular geometric shape from the wells by enlarging the area of contacting them. For that purpose, it has been developed a fundamentally new design of the large-diameter fishing tool with the moving magnetic systems capable of copying the shape of the objects to be fished. Each magnetic system, which is compound of permanent rare-earth neodymium magnets and concentrically placed magnetic cores, shall be held by the magnetic field of adjacent systems with opposite polarity. There were conducted theoretical studies using the finite element method to determine the working capacity of the designed tool. As a result, it has been found the value of hoisting capacity during the interaction of magnetic systems with the roller cone of the drill bit; this fact confirms the capability of fishing the objects of irregular geometric shape. In addition, it has been explored the influence of the material of the fished object on the power characteristics of magnetic systems. The application of the designed magnetic tool allows removing the ferromagnetic objects from the well regardless of their shape, weight and position on the bottom hole. Apart from that, the given tool may be used in the areas where the technology of work is related to drilling wells.
One of the main elements of control over wells in the process of their construction is the blowout equipment, which includes annular preventers. This also applies to wells that provide degassing of coal veins to reduce their gas dynamic activity. Modern technology of work requires expansion of the functionality of the sealing unit of the annular preventers with the simultaneous provision of its operational characteristics. Determining the necessary durability of seals for different operating modes is the study of their stress-strain state. The paper deals with the possibility of using simulation modeling in the annular preventers design situations and within the study of the armature geometry influence of the sealant fittings on its stress-strain state. The method of determining the material constants to realize the Mooney-Rivlin model has been proposed. The behavior of low-density rubber in software product has been described by the finite element method. The aggregation error of experimental and theoretical studies is 5%. Therefore, the preconditions and the possibility of using simulation modeling in the design of annular preventers devices with increased operational characteristics have been created and confirmed.
One of the basic methods of mechanical rock mining is cutting, which faces increasingly difficult working conditions. Despite the rapid development of machines used in underground and opencast mining as well as in tunnel building, construction industry and road engineering, the problem of insufficient durability of mining tools remains unsolved. In addition to drilling and, to a lesser extent, planing, cutting provides a huge market for tools. Currently, the process of cutting is mainly based on conical picks. The cutterheads of cutting machines are equipped with several dozen, and frequently – more than one hundred conical picks, which, due to their workability and abrasiveness, sometimes work only a few hours. There is a market demand for over two hundred models of conical picks. This is due to the huge variety of shapes and sizes of picks as well as the methods of their mounting in the holder. The article briefly presents various solutions of conical picks, their construction, methods of protection, dimensions and materials used. Next, based on materials produced by ZWM Carbonex, the classic method of their manufacture using the turning technology has been described. The authors have also presented briefly the use of die forging for the large-scale production of picks, applied by Górnicza Fabryka Narzędzi Sp. z o.o.
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