Assessment of the quality of the crankshaft grinding process for repair size

Mechanical processing of critical parts affects the quality of engine repair. The authors carried out research to assess the quality of setting for machining the crankshaft main journals of the ZMZ engine for the repair size. They studied the diameters of 20 crankshaft main journals of the ZMZ engine after machining for the repair size. The diameters were controlled by a lever clamp SR-75. The following tools were sequentially used to evaluate the quality of machining main bearing journals: a “box-and-whisker” diagram, Shewhart control charts, and a histogram. According to the “Box and Whiskers” diagram it was found that after machining for the repair size all the journals have a diameter within the machining tolerance field, but at the same time there is a scatter between the diameters of the journals of the same crankshaft. After analyzing the Shewhart control charts, it was found that the scatter values within one subgroup (crankshaft) and between the subgroups were caused by the usual reasons, and this scatter pattern can be considered random. Consequently, the technological process can be considered stable and controllable. The histogram helped to determine the probability of correctable rejects after machining of the engine journal for the repair size, equal to 1.95%, and the probability of irreparable rejects, equal to 0. The calculated reproducibility index of 0.93 indicates a significant wear of the equipment. Over time, the index will decrease and the risks of rejects will increase. The authors conclude that the quality of setting for machining crankshaft main bearing journals for the repair size is acceptable. It is desirable to regularly check the quality of machining crankshaft main journals for the repair size, consistently applying all the three tools to identify the size variation and inconsistencies, which is especially relevant for worn equipment.

1. Erokhin M.N., Leonov O.A., Shkaruba N.J. Vergazova Yu.G., Skorokhodov D.M. Production and repair of domestic machines for agroindustrial complexes from the position of the 5M principle. Vestnik Mashinostroeniya. 2023;8:701-704. (In Russ.) https://doi.org/10.36652/0042-4633-2023-102-8-701-704

2. Burak P.I., Golubev I.G. Renewal of the park of agricultural machinery with the framework of the departmental project ″technical modernization of the agro-industrial complex″. Machinery and Equipment for Rural Area. 2023;7:2-7. (In Russ.) https://doi.org/10.33267/2072-9642-2023-7-2-7

3. Malykha E.F., Kataev Yu.V., Zakarchevski O.V., Tarasova V.A. Criteria for the formation and development of the secondary market of used agricultural machinery. Ekonomika, Trud, Upravlenie v Selskom Khozyaystve. 2021;6:103-109. (In Russ.) https://doi.org/10.33938/216-103

4. Kushnarev L.I., Sevostyanova D.L. On high-repeatablity quality of engineering industry products. Remont. Vosstanovlenie. Modernizatsiya. 2022;2:32-36. (In Russ.)

5. Kornilovich S.A., Trofimov B.S. Precision, stability analysis of the crankshaft grinding technological process. The Russian Automobile and Highway Industry Journal. 2018;15(6):878-885. (In Russ.)

6. Tarasenko B., Dzjasheev A.M., Markov V., Zagidullin R., Akhmetshin S., Yakushev A. Method for repairing steel crankshaft joints. E3S Web of Conferences: II International Conference on Environmental Technologies and Engineering for Sustainable Development (ETESD-II 2023). Tashkent: EDP Sciences. 2023;443:04005. https://doi.org/10.1051/e3sconf/202344304005

7. Kumaran S.V., Wahab D.A., Aziz N.A., Wahid Z. Guidelines for automotive component repair using additive manufacturing in industry 4.0: design and process perspective. Journal of Information System and Technology Management. 2024;9:20-32. https://doi.org/10.35631/JISTM.934002

8. Aziz N.A., Elanggoven L., Wahab D.A, Zakaria A., Kamarulzaman N., Awang N. Failure-based design validation for effective repair of multi-metal additive manufacturing: the case of remanufacturable brake caliper. International Journal of Advanced Manufacturing Technology. 2024;132:1425-1437. https://doi.org/10.1007/s00170-024-13425-x

9. Skovorodin V.Ya., Antipov A.V. The effect of mode of finishing of crankshaft journals on anti-friction surface properties. Izvestiya Mezhdunarodnoy Akademii Agrarnogo Obrazovaniya. 2018;41-1:38-43. (In Russ.)

10. Rozno M.I. Statistical acceptance quality control: properties and capabilities. Part I. Production Quality Control. 2020;9:32-39. (In Russ.)

11. Brish V.N., Starostin A.V., Osipov Yu.R. Applicability of statistical methods of analysis and quality control of engineering products at different stages of production. Fundamentalnye Issledovaniya = Fundamental Research. 2016;12-4:719-724. (In Russ.)

12. Shper V.L. Quality tools and something more! Part 3. Where to begin (to be continued). Metody Menedzhmenta Kachestva = Methods of Quality Management. 2021;3:48-54. (In Russ.)

13. Rogozhina E.A., Tverskoy O.Yu. Comparing the types of Shewhart control charts for quantitative data through the verification of the developed algorithms. Promyshlennost i Selskoe Khozyaystvo. 2022;1:46-56. (In Russ.)