| Abstrakt: |
The peculiarities of manufacturing drill bits and cutters are considered and studied. The carried out analysis of operation of working bodies of drill bit frames showed that during drilling most often a wear of cutters, a protective coating of sitters and a calibrating surface of frames of drilling bits occur. It was investigated that in arc surfacing using TIG method, low rates of heating and cooling of metal during preheating of working bodies of a bit allow reducing residual stresses and avoiding the formation of cracks in coatings and base material. It was established that the optimal thickness of surfacing the protective coating should be within 2.0…3.0 mm, where a uniform distribution of tungsten carbides throughout the volume of the deposited layer is observed, which effectively resists wear of the working bodies of blades and frames of bits in the conditions of alternating and shock loads, hydroabrasive wear, corrosion, erosion, etc. It was established that bits with a protective coating, having a high wear and corrosion resistance, increase the mechanical speed of drilling and solve the most important task of reducing the number of lowering and lifting operations when drilling gas and oil wells. As a result of carried out production tests of manufactured drill bits, it was found that protective coating of working bodies allows extending the service life. 18 Ref., 1 Tabl., 8 Fig. [ABSTRACT FROM AUTHOR] |
