Drilling oil and gas wells is a complex, time-consuming and expensive operation. When drilling oil and gas wells, the bottom of the drill string is: heavy drill pipes (HDP), thick-walled drill pipes (TDP), steel drill pipes (SDP). The main problems of low durability of drill pipes (DP) are abrasive wear of the locks, wear of the external and internal conical tool joints. More than 60% of the pipes are rejected due to wear of the outer diameter of the lock. The main reason for drill pipe tool joints to wear in the open hole is the presence of a hard layer in aggressive geological formations and wear due to friction with the inner wall of the casing. SDPs are composite, with locks welded to the pipe body by friction welding. SDP locks are made of high-quality structural low-alloy steels of type 4140 and subjected to heat treatment. DP length is 8.5–12.5 m. In the process of drilling wells, the lower part of the drill string is in direct contact with the abrasive particles of rock-breaking formations. The rate of destruction of DP surface layers during abrasive wear is practically independent of the initial strength properties of the lock material. The chemical composition of the material of drill pipe tool joints indicates a significant dispersion of steels in terms of the carbon content (0.22–0.37), which, in combination with other alloying elements, corresponds to steel grades 20 CrMoV_40 CrMoV. The hardness of the material of the lock part of DP is 28–36 HRC and is provided by induction volumetric heat treatment. In order to increase DP durability, belts with wear-resistant materials are applied to the outer diameter of the locks by surfacing. Most often there are three such belts, each of which has a width of 25.4 mm with a total width of 76.2 ± 6.35 mm. Surfacing of the belts is performed in an argon medium. Deposited metal rises above the lock body by up to 2.5 mm. This method of increasing the durability of DP is widely used by foreign companies. Thus, one of the priority areas in the production and overhaul of drill pipes was hardening surfacing with wear-resistant materials (hardbanding) of the outer surface of the joints. Hardbanding is a wear-resistant protective metal coating applied by electric welding to the outer surface of the drill pipe joint in order to increase the resource of the castle and reduce wear of the casing string.
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