2020 №06 (07) DOI of Article
2020 №06 (01)

Automatic Welding 2020 #06
Avtomaticheskaya Svarka (Automatic Welding), #6, 2020, pp. 45-50

Peculiarities of repair of worn areas of drill bit bodies

B.V. Stefaniv
E.O. Paton Electric Welding Institute of the NAS of Ukraine, 11 Kazymyr Malevych Str., 03150, Kyiv, Ukraine. E-mail: office@paton.kiev.ua

The peculiarities of wear of operating elements of the bodies of steel, matrix drill bits and heads were considered and studied, and repairability criteria were determined. Performed analysis of worn areas of operating elements of used drill bit bodies showed that at drilling wear of cutters and seats is the most common, and wear of flushing components of the drill bit bodies occurs less often. Metallographic examination showed that the deposited layer and the base metal are connected by a thin transition layer of diffusion origin, which shows that base metal melting and filler metal dissolution did not occur in it. It is established that the drill bit repair is cost-effective in those cases, when the cost of such repair does not exceed one third of the cost of the bit proper. Multiple repeated reconditioning of operating elements of worn areas reduces the cost of manufacturing new drill bits several times. Conducted production trials of reconditioned drill bits showed that repair of worn areas of the operating elements allows considerable extension of the service life and saving 30…50 % of the initial cost of a specific drill bit type. 12 Ref., 2 Tabl., 8 Fig.
Keywords: wear, surfacing, tungsten carbides, area, bridge, diamond-carbide cutter (DCC), polycrystalline diamond cutter (PDC), carbide coating (CC), microstructure, wear resistance.

Received: 02.06.2020


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