Research On The Key Technologies Of High Neck Flange Forming With Closed Ring Rolling Technology

High neck flange closed rolling by ring rolling mill is one of the advanced plastic formingprocess with high efficiency, low energy consumption and good quality of product, etc. Thediameter of the flange blank increases as its cross-section decreases during the rolling process. Atpresent, the research on the ring with rectangular section and step section forming by the ringrolling technology has made great achievements, while the research on the ring with complexcross-section forming with the ring rolling technology is still at an early stage which limits thedevelopment of this technology. Therefore, it has great significance to expanding applied fields ofring rolling method and meeting the demand of forming complex cross-section ring with moreefficient and lower cost by make efforts in research on the high neck flange forming by closed ringrolling technology.This paper based on the ring rolling theory, established the mechanical model for the processof hign neck flange closed rolling, derived the formulas of the limited process parameters androlling parameters. The finite element model(FEM) for high neck flange closed rolling process wasset up by DEFORM software. The rolling process of four classical structure flange blanks weresimulated by FEM and the optimal flange blank which has inclined neck and internal tapered holehas been obtained. The parametrization design of the optimal flange blank has also been realizeddue to the design formulas of flange blank has been derived. Through simulation, the metal flowrules and strain-stress distribution rules during the high neck flange closed rolling process wereobtained and the mechanism of rolling defects was also explained. The optimal process parameterswere obtained as the influences of the parameters to the quality of product and rolling parameterswere analyzed. The motion equations of guiding rolling were derived through the research onmovement of guiding rolling during the rolling process and the best position angle with15degreeof guiding rolling was obtained after analyzing the influences of the guiding roll position to thequality of product. Moreover, the rolling experiments of high neck closed rolling were made in ringrolling mill with type of D51-450by self-designed mould. The reliability of the finite elementsimulation has been proved by comparing the simulation results with the experiment results.The research results in this paper innovated the process of forming the high neck flange andrealized the computer aided design of high neck flange blank’s structural parameters and process parameters. It is of great scientific importance for increasing production quality and productionefficiency and improving the high neck flange closed rolling theory.