Tehnički vjesnik, Vol. 21 No. 6, 2014.
Stručni rad
A contribution to research on the cause of axle assembly expansions of exploited freight wagons
Vili Milković
orcid.org/0000-0002-2723-147X
; HŽ Cargo, Sarajevska 43, 10000 Zagreb, Croatia
Dennis Jankovich
orcid.org/0000-0003-3535-5963
; Tehnokom d.o.o, Radnička cesta 228, 10000 Zagreb, Croatia
Dragutin Lisjak
orcid.org/0000-0002-9976-577X
; University of Zagreb, Faculty of Mechanical Engineering and Naval Architecture, Ivana Lučića 5, 10000 Zagreb, Croatia
Sažetak
A railway wheel, together with an axle, is one of the crucial parts that support the safe operation of freight wagons. In exploitation the wheels of freight cars are exposed to high heat warmings causing stresses and possible mechanical failures due to wear and geometric distance, especially when it runs directly over the break shoes. This paper gives an overview of the research on the cause of axle assembly expansions of Croatian Railways’ freight wagons. The results of the research show that the widening of the wheel distance outside the tolerant limits depends on the residual stresses within the wheels themselves, and on the diameter of the wheels. Multiple regression analysis has shown to be the optimal statistical method for linking these phenomena. By analysing malfunctions concerning wheel expansions on train wagon series, a series with most frequent malfunctions has been singled out, while the main cause of these malfunctions is the manufacturer of wheel equipment A.
Ključne riječi
axle assembly; residual stress; malfunction frequency
Hrčak ID:
131338
URI
Datum izdavanja:
21.12.2014.
Posjeta: 2.510 *