Belgorod State University, Belgorod, Russia:

N. A. Pelipenko, Professor, Doctor of Engineering Sciences, pelipenkona@mail.ru
R. R. Baklanov, Post-Graduate Student

The article describes the methods of accelerated reliability, strength, wear resistance and cutting capability testing of drilling tools. The design solutions are proposed for the comparative accelerated testing of cutting elements—plates, cutters, crowns, at their contact with rocks of various hardness and abrasiveness. The design of the experimental setup using the weight method of wear control with regard to geometric parameters of a tool is proposed. The nature and amount of wear are duplicated by testing samples on the machine MI-1M, which ensures satisfactory assessment of the wear rate. Based on the dependencies and patterns obtained, it is possible to create a mathematical model of the drilling process with the assessment of the reliability and durability of tools. The proposed approach allows optimizing the cost of drilling. In practice, the tools equipped with diamonds, hard-alloy plates and pins are often unjustifiably used, which is confirmed by the experimental studies. The accelerated testsare needed to determine the actual cutting parameters. It is noticed that a new tool is characterized by a higher productivity, which, with the wear of the tool, i.e. with the change in the geometry of the cutting part of the tool, decreases with the simultaneous increase in the torque and axial force of the tool. Tests of cutting tools on an experimental plant open up opportunities for improving the design of the tools, as well as for creating special mobile small-sized devices for periodic restoration of geometry of cutting elements immediately in operation. The proposed plant was designed by the scientists of the Applied Geology and Mining Department of the Belgorod State University and can be used by scientific organizations and production companies associated with rock drilling, including under a business contract.

1. Heinrichs J., Olsson M., Yvell K., Jacobson S. On the deformation mechanisms of cemented carbide in rock drilling—Fundamental studies involving sliding contact against a rock crystal tip. International Journal of Refractory Metals and Hard Materials. 2018. Vol. 77. pp. 141–151.
2. Muminov R. O., Kuziev D. A., Zotov V. V., Sazankova E. S. Performability of electro-hydro-mechanical rotary head of drill rig in open pit mining: A case-study. Eurasian Mining. 2022. No. 1. pp. 76–80. DOI: 10.17580/em.2022.01.16
3. Macias F. J., Dahl F., Bruland A. New Rock Abrasi vity Test Method for Tool Life Assessments on Hard Rock Tunnel Boring: The Rolling Indentation Abrasion Test (RIAT). Rock Mechanics and Rock Engineering. 2016. Vol. 49, Iss. 5. pp. 1679–1693.
4. Küpferle J., Röttger A., Alber M., Theisen W. Assessment of the LCPC abrasiveness test from the view of material science. Geomechanics and Tunneling. 2015. Vol. 8, Iss. 3. pp. 211–220.
5. Plinninger R. J. Abrasiveness Assessment for Hard Rock Drilling. Geomechanics and Tunnelling. 2008. Vol. 1, Iss. 1. pp. 38–46.
6. Alber M., Yaralı O., Dahl F., Bruland A., Käsling H. et al. ISRM Suggested Method for Dete rmining the Abrasivity of Rock by the CERCHAR Abrasivity Test. Rock Mechanics and Rock Engineering. 2014. Vol. 47, Iss. 1. pp. 261–266.
7. Düllmann J., Alber M., Plinninger R. J. Determining soil abrasiveness by use of index tests versus using intrinsic soil parameters. Geomechanics and Tunnelling. 2014. Vol. 7, Iss. 1. pp. 87–97.
8. Coombes M. A., Feal-Pérez A., Naylor L., Wilhelm K. A non-destructive tool for detecting changes in the hardness of engineering materials: Application of the Equotip durometer in the coastal zone. Engineering Geology. 2013. Vol. 167. pp. 14–19.
9. Mol L., Viles H. A. The role of rock surface hardness and internal moisture in tafoni development in sandstone. Earth Surface Processes and Landforms. 2012. Vol. 37, Iss. 3. pp. 301–314.
10. Hisashi Aoki, Yukinori Matsukura. Estimating the unconfined compressive strength of intact rocks from Equotip hardness. Bulletin of Engineering Geology and the Environment. 2008. Vol. 67, Iss. 1. pp. 23–29.
11. Shalabi F. I., Cording E. J., Al-Hattamleh O. H. Estimation of rock engineering properties using hardness tests. Engineering Geology. 2007. Vol. 90, Iss. 3-4. pp. 138–147.
12. Boutrid A., Bensihamdi S., Chettibi M., Talhi K. Strength hardness rock testing. Journal of Mining Science. 2015. Vol. 51, Iss. 1. pp. 95–110.
13. Hoek E., Martin C. D. Fracture initiation and propagation in intact rock—A review. Journal of Rock Mechanics and Geotechnical Engineering. 2014. Vol. 6, Iss. 4. pp. 287–300.
14. Scholtès L., Donzé F.-V. A DEM model for soft and hard rocks: Role of grain interlocking on strength. Journal of the Mech anics and Physics of Solids. 2013. Vol. 61, Iss. 2. pp. 352–369.
15. Nicksiar M., Martin C. D. Crack initiation stress in low porosity crystalline and sedimentary rocks. Engineering Geology. 2013. Vol. 154. pp. 64–76.
16. Diederichs M. S. Manuel Rocha Medal Recipient Rock Fracture and Collapse Under Low Confinement Conditions. Rock Mechanics and Rock Engineering. 2003. Vol. 36, Iss. 5. pp. 339–381.
17. Enru Liu. Effects of fracture aperture and roughness on hydraulic and mechanical properties of rocks: implication of seismic characterization of fractured reservoirs. Journal of Geophysics and Engineering. 2005. Vol. 2, Iss. 1. pp. 38–47.
18. Mussa A., Krakhmalev P., Bergström J. Sliding wear and fatigu e cracking damage mechanisms in reciprocal and unidirectional sliding of high-strength steels in dry contact. Wear. 2020. Vol. 444-445. 203119. DOI: 10.1016/j.wear.2019.203119
19. Momeni S., Moseley S., Ante M., Allaart J. The wear of WC-Co drill bits during rotary-percussive drilling of reinforced concrete. International Journal of Refractory Metals and Hard Materials. 2017. Vol. 62. pp. 202–209.
20. Abu Bakar M. Z., Majeed Y., Rostami J. Influence of moisture co ntent on the LCPC test results and its implications on tool wear in mechanized tunneling. Tunnelling and Underground Space Technology. 2018. Vol. 81. pp. 165–175.
21. Talerov M. P., Bolobov V. I. Life and failures of tangential-rotary picks. Gornyi Zhurnal. 2018. No. 4. pp. 77–81. DOI: 10.17580/gzh.2018.04.14
22. Pelipenko N. A., Protsuk I. S., Dobrynin V. E., Grekhovodov I. I. For the question about the physics of the hard rock drilling. Vestnik Assotsiatsii burovykh podryadchikov. 2016. No. 3. pp. 14–17.
23. Pinakhin I. A., Chernigovskiy V. A., Bratsikhin A. A., Yagmurov M. A., Sugarov Kh. R. et al. Complex study of physical and mechanical properties of VK6, VK8, and T5K10 hard alloys subjected to volumetric impulse laser hardening. Industrial Laboratory. 2017. Vol. 83, No. 3. pp. 37–40.
24. Shakhova K. I., Kovalevskaya A. Yu. Analysis and reliability enhancement of hard-alloy components of drill bits. GIAB. 2004. No. 4. pp. 231–234.
25. Khayretdinov E. F., Raab G. I., Nabiullin A. A., Bikbulatova V. Z., Sitdikov V. D. et al. Formation of the structure and properties of a high speed steel tool by severe plastic deformation andsubsequent heat treatment. Material Physics and Mechanics. 2016. Vol. 27, No. 2. pp. 205–214.
26. Pelipenko N. A., Ignatenko I. M. Vibropercussion polyindenter drilling assembly. GIAB. 2019. No. 9. pp. 195–203.
27. Pelipenko N. A., Protsuk I. S., Baklanov R. R. Results of experimental research drilling process. Vestnik assotsiatsii burovykh podryadchikov. 2019. No. 2. pp. 41–44.
28. Goncharov P. N., Korshunov V. Ya. Experimental research procedure for sample wear testing on friction machine MI-1M. Vestnik Bryanskoy gosudarstvennoy selskokhozyaystvennoy akademii. 2014. No. 3. pp. 67–69.