STUDY OF THE IMPACT OF OPERATIONAL FACTORS ON THE EFFICIENCY OF MAGNETIC FISHING TOOL

Abstract

The process of constructing oil and gas wells is accompanied by periodic failures and breakdowns of drilling tools, resulting in metal fragments of various shapes and weights remaining at the bottom of the well. Magnetic capture devices are widely used to prevent accidents and to clean the bottom of oil and gas wells of metal objects. Permanent magnet based trapping devices operate under harsh conditions that become more complicated as the well depth increases. Therefore, the objective of this work is to investigate the influence of operational factors on the efficiency of magnetic devices. To this end, we have analyzed the operating conditions and identified the factors that affect the operation of permanent magnet traps. These include: well diameter and orientation, type of flushing fluid, mass, size and material of accidental debris, presence of mud on the well, vibration, shock, pressure and temperature. Theoretical studies using the finite element method were conducted to determine the effect of high temperatures on the force characteristics of the magnetic systems of the collectors. As a result, the lifting force values for magnetic systems with different brands of permanent magnets were obtained. It was found that the force characteristics of the systems decrease with increasing ambient temperature. When the upper limit of the operating temperature of permanent magnets is exceeded, the decrease of the lifting force is much faster. The influence of the length of permanent magnets on the thermal stability of magnetic systems is also investigated. Recommendations for the use of rare-earth neodymium permanent magnets in magnetic systems of wellhead traps of various depths have been developed.