APPLICATION FEATURES OF NEW STRUCTURAL STEEL 20KHN3MA FOR LARGE-SIZED CASE-HARDENING GEARS

VITYAZ Pyotr A., D. Sc. in Eng., Academician of NAS of Belarus, Head of the Departmemt of Mechanical Engineering Technologies and Metallurgy, Joint Institute of Mechanical Engineering of the National Academy of Sciences of Belarus, Minsk, Republic of Belarus

MOISEENKO Vladimir I., D. Sc. in Eng., Prof., Chief Researcher of the Laboratory of Reliability Problems and Metal Intensity of High- and Extra-High Capacity Dump Trucks, Joint Institute of Mechanical Engineering of the National Academy of Sciences of Belarus, Minsk, Republic of Belarus

SIDORENKO Alexander G., Ph. D. in Eng., Head of the Laboratory of Reliability Problems and Metal Intensity of High- and Extra-High Capacity Dump Trucks, Joint Institute of Mechanical Engineering of the National Academy of Sciences of Belarus, Minsk, Republic of Belarus

TOMASHEVSKY Dmitry G., Junior Researcher, Joint Institute of Mechanical Engineering of the National Academy of Sciences of Belarus, Minsk, Republic of Belarus

SHISHKO Sergey A., Deputy Chief Designer, OJSC “BELAZ” — Management Company of Holding “BELAZ-HOLDING”, Zhodino, Republic of Belarus

The paper gives an analysis and an assessment of the applicability of the most well-known grades of steels used for making large-sized case-hardening gears. It was found that increasing the hardness of the cemented tooth surface with simultaneous provision and preservation of its specified direction is a complex and important task in the creation of case-hardening gears. The features of the change in the dimensions of parts are studied depending on the degree of their nickel alloying. The use of a new material – steel 20KhN3MA – is proposed, which allows us to increase the strength, accuracy, reliability and life of large-sized gears. Of particular interest is the steel 20KhN3MA, as it is poorly deformed during technological alterations and in operation, it is used for large-sized gears of high-power reduction gear systems and for non-grinding cogwheels, first of all with a circular tooth. The material presented in this paper is of interest and can be useful for scientists and engineering services of the engineering industry.

service lifetime, strength, reliability, gears, warping, transmission, alloying, case hardening

• Rudenko S.P., Valko A.L. Osobennosti rascheta zubchatykh koles transmissiy na glubinnuyu kontaktnuyu vynoslivost [Peculiarities of calculation of gears of transmissions on deep contact endurance]. Vestnik mashinostroeniya [Bulletin of mechanical engineering], 2015, no. 11, pp. 5–11.
• Naskovets A.M., e.a. Karernye samosvaly osobo bolshoy gruzopodemnosti dlya dorog s povyshennymi uklonami [Dump trucks of extra-large payload capacity for high gradient roads]. Trudy mezhdunarodnogo nauchnogo foruma “Mekhanika – mashinostroeniyu” [Proc. of the International Scientific Forum “Mechanics for Mechanical Engineering”]. Minsk, 2010, pp. 34–40.
• GOST 21354-87. Peredachi zubchatye tsilindricheskie evolventnye vneshnego zatsepleniya. Raschet na prochnost [State Standard 21354-87. Cylindrical evolvent gears of external engagement. Strength calculation]. Moscow, Izdatelstvo standartov Publ., 1988. 125 p.
• Chernavskov S.A., Reshhikov V.F. Spravochnik metallista: v 5-ti t.: T. 1 [Reference book of metalworker: in 5 vol. Vol. 1]. 3rd ed. Moscow, Mashinostroenie Publ., 1976. 768 p.
• Vulgakov E.B. Spravochnik: Aviatsionnye zubchatye peredachi i reduktory [Reference book: Aviation gears and reducers]. Мoscow, Mashinostroenie Publ, 1981. 374 p.
• The Black Book 1984: Steel Data, Poductdata, Tables. Danderyd, SKF Steel, 1984. 250 p.
• Mariev P.L. Povyshenie konstruktsionnoy ravnoprochnosti krupnogabaritnykh detaley i svarnykh uzlov karernykh samosvalov [Increasing the structural equal strength of large-sized parts and welded assemblies of dump trucks]. Minsk, Institut tekhnicheskoy kibernetiki NAN Belarusi Publ., 2001. 180 p.
• Tayts B.A. Spravochnik: Proizvodstvo zubchatykh koles [Reference book: Gears manufacturing]. 3rd ed. Moscow, Mashinostroenie Publ., 1990. 464 p.
• Moiseenko V.I., Mariev P.L. Osnovy strukturnoy ravnoprochnosti krupnogabaritnykh detaley i svarnykh uzlov karyernykh samosvalov [Fundamentals of structural equal strength of steel and elements of large-sized machine parts]. Minsk, Institut tekhnicheskoy kibernetiki NAN Belarusi Publ., 1999. 200 p.
• Gudremon E.A. Spetsialnye stali [Special steels]. Moscow, Metallurgiya Publ., 1966. 734 p.
• Kozlovsky I.S. Khimiko-termicheskaya obrabotka shesteren [Chemical heat treatment of gears]. Moscow, Mashinostroenie Publ, 1970. 232 p.
• Moiseenko V.I., Shkatulo N.D. Konstruktsionnaya legirovannaya stal [Structural alloyed steel]. Patent RB, no. 16513, 2012.
• Rudenko S.P., Valko A.L., Shipko A.A., Bylitskiy V.V., Karpovich P.G. Povyshenie ekspluatatsionnykh kharakteristik zubchatykh koles karernykh samosvalov posredstvom optimizatsii rezhimov khimiko-termicheskoy obrabotki [Improving the performance characteristics of gears for dump trucks by optimizing the modes of chemical-thermal treatment]. Lite i metallurgiya [Casting and metallurgy], 2013, no. 2, pp. 110–114.