Journals →  Chernye Metally →  2019 →  #11 →  Back

Engineering Technologies
ArticleName Reducing the influence of technological heredity on the accuracy of honed cylinder workpieces using natural aging
ArticleAuthor A. S. Yamnikov, L. L. Safarova
ArticleAuthorData

Tula State University (Tula, Russia):

A. S. Yamnikov, Dr. Eng., Prof., Dept. “Machinebuilding Technology”, E-mail: yamnikovas@mail.ru

 

JSC “Tulamashzavod” (Tula, Russia):
L. L. Safarova, Technologist, Post-Graduate, E-mail: l.bashkirceva@mail.ru

Abstract

The widespread use of cast iron castings for workpieces of parts with a complex shape, subjected to high thermal and mechanical stresses during operation, has been explained. A review of domestic and foreign literature is presented, showing the interest of researchers in improving the chemical composition of special cast irons and the influence of individual components on the heat resistance and wear resistance of cast iron parts. It is noted that the heterogeneity of the structure of castings results in susceptibility to changes in their size and shape obtained after the final machining of critical surfaces. The works of Russian scientists are proposed, offering to carry out operations on aging workpieces to stabilize their size and shape. The results of the study of the density distribution over the cross section of a cylinder casting are analyzed using X-ray computed tomography of a diesel engine cylinder, conducted by employees of JSC “Tulamashzavod”, which showed that the density of the metal in the casting varies in a range of 6.75 ÷ 7.25 g/cm3. The influence of the method of performing the natural aging operation on the accuracy of the part was established. The results of changes in dimensional accuracy after applying two variants of natural aging to a batch of Cylinder parts were presented: natural aging for six months, stabilizing tempering before finishing machining, waiting time of parts for three days after the final honing and natural aging for six months, waiting time of parts within 12 days after the final honing. Measurements were made in four sections (eight points in each section) according to a calendar schedule corresponding to casting aging technology. It was established that in both aging variants, the change in the size of the finished part decreases from 3 ÷ 10 μm without aging to 0 ÷ 5 μm. Based on the studies, JSC Tulamashzavod decided to carry out natural aging of the workpieces within six months and stabilizing tempering before the operation of honing the workpieces for the Cylinder parts.

keywords Cast iron, cylinder, diesel, size and shape accuracy, natural aging, tomogram, honing
References

1. GOST 7769–82. Alloy cast iron for castings of special properties. Grades. Introduced: 01.01.1983.
2. Irons, their properties and application areas. [Electronic resource] Available at: http://mkkrasnoyarsk.ru/d/1624922/d/chugun_kharki.pdf (accessed: 22.04.2019).
3. Andreev V. V. Features of formation of the cast structure of highstrength cast irons and development of effective technologies for manufacture of castings with high performance parameters: thesis of inauguration of Dissertation … of Doctor of Engineering Sciences. Moscow, 2012. 79 p.
4. Zhenting W., Hongming G. Investigation on microstructure and wear resistance of the new Cr-W-Mo-V high-alloy wear resistant cast iron. Advanced Materials Research. 2015. Vol. 1061–1062. pp. 670–673.
5. Gromczyk М., Kondracki М., Studnicki А., Szajnar D. Stereological analysis of carbides in hypoeutectic chromium cast iron. Archives of Foundry Engineering. 2015. Vol. 15. Iss. 2. pp. 17–22.
6. Richards V., Anish T. V., Lekakh S. Age Strengthening of Gray Iron — Kinetics Study. International Journal of Metalcasting. 2008. Vol. 2. Iss. 1. pp. 7–16.
7. Teague J. A., Richards V. L., Lekakh S. N., Peaslee K. D. Age Strengthening and Machinability Interactions in Gray Cast Iron. International Journal of Metalcasting. 2010. Vol. 4. Iss. 2. pp. 45–57.
8. Lekakh S. N., Richards V. L., Teague J., Peaslee K. Aging and Machinability of Irons with Compact and Spheroidal Graphite. AFS Transactions. 2010. Vol. 118. pp. 181–193.
9. Murthy A. S., Lekakh S., Richards V. L., Aken D. V. On The Homogenization of Cobalt Modified 17-4 PH Stainless Steel. EPD Congress 2011. Proceedings of the TMS Annual Meeting. 2011. February 27 — March 4. pp. 651–658.
10. Biswas S., Monroe C., Prucha T. Use of Published Experimental Results to Validate Approaches to Gray and Ductile Iron Mechanical Properties Prediction. International Journal of Metalcasting. 2017. Vol. 11. Iss. 4. pp. 656–674.
11. Lekakh S., Richards V. L. Cast iron mach inability: the effect of aging on material properties determines the optimal machining time. AFS Proceedings. 2012. 11 p.
12. Method of the National Standard Reference Data Service. GSSSD ME 106-97. Iron. Dimensional stability after combined aging. Introduced: 24.09.97., No. 771 — 97 кк.
13. Vasilyev А. S. Technological inheritance in mechanical engineering. Vestnik Rybinskoy gosudarstvennoy aviatsionnoy tekhnologicheskoy akademii imeni P. A. Solovyeva. 2017. No. 1 (40). pp. 198–202.
14. Matveev I. А., Yamnikov А. S. Yamnikova О. А. Influence of the type of an initial workpiece on accuracy of manufacturing extended axisymmetric cases. Vestnik mashinostroeniya. 2018. No. 3. pp. 45–49.
15. Vasilyev А. S., Yamnikov А. S., Yamnikova О. А., Matveev I. А. Influence of hereditary technological errors of production of a basic pipe on parameters of the assembled propulsion section. Chernye Metally. 2019. No. 1. pp. 67–71.
16. Yamnikov А. S., Boriskin О. I., Yamnikova О. А., Matveev I. А. Technological inheritance of the properties of an initial billet in the accuracy parameters of extended axisymmetric parts. Chernye Metally. 2017. No. 12. pp. 50–56.
17. Vasilyev А. S., Dalsky А. М., Zolotarevsky Yu. М., Kondakov А. I. Directional formation of properties of engineering products. Edited by Kondakov А. I. Moscow: Mashinostroenie, 2005. 351 p.
18. JSC “Tulamashzavod. [Electronic resource]. Available at: www.tulamash.ru (accessed: 03.10.2019).
19. GOST R 53464–2009. Metal and alloy castings. Dimensions and mass tolerances and machining allowances. Moscow: Standartinform, 2010. 62 p.
20. Yamnikov А. S., Safarova L. L. Abbot chart synthesis. Izvestiya TulGU. Technicheskie nauki. 2018. No. 8. pp. 30–35.
21. Dronov Е. А., Barakhov V. I., Samochkin V. N. Application of X-ray computed tomography to determine the cause of diesel engine cylinder jamming. Izvestiya TulGU. Technicheskie nauki. 2016. No. 12 (2). pp. 39–47.

Language of full-text russian
Full content Buy
Back