The influence of initial blank parameters on railway wheels manufacture with hot plastic deformation process

Abstract

The current article aims at simulation of hot plastic deformation process with the objective to determine the influence of initial blank H / D ratio on the cumulative deformation distribution within the wheel blank and position of its axial zone with its macrostructure improper quality. The methods of mathematical simulation have been applied for metal yield at the main stages of wheel blank hot plastic deformation (upset forging, spread and die forging) and simulation is carried out with program “Forge 3”. The research results are in the assessment performed for the deformed metal within the wheel volume and the research has been made with computer simulation of the hot plastic deformation for the wheel blanks with Ø 360 – 520 mm and shape form of H/D = 0.5– 1.6. The research has determined that the optimal initial blank for production of Ø 957-mm-railway wheels is the wheel blank of Ø 450 mm (H / D = 0.84) and its application enables fine workability of the wheel rim (the value of the cumulative degree of deformation is 85%) and that of the wheel disk is 92 %, this practice also excludes occasional defects of macrostructure to be present in the wheel. The scientific novelty of the current paper is in featuring the influence of initial blank geometry on the distribution of cumulative deformation and position of axial low-quality zone of the macrostructure in wheel blanks after hot plastic deformation. It has been found that on condition when wheel blank shape (H / D) is 0.73, 0.84 or 1.11, cumulative degree of deformation in wheel rim change insignificantly and is of 85 %. The practical value of the paper we see in determining the best possible or optimal initial blank for production of railway wheels with Ø 957 mm in diameter (a blank of Ø 450 mm and its H / D = 0.84), application of which provides good industrial results stated above.