The Study Of Extrusion Process For Crank Of Large Composed Marine Crankshaft

Crankshaft forgings is one of the most complex forgings, marine crankshaft is important components of marine diesel engine . Crank of large composed marine crankshaft is the key parts of marine crankshaft.Force situation of Crank in the work is complex, Under the premise of guaranteeing quality, reducing machining allowances is a very important issue in the process of large marine crankshaft crank forging.To reduce the allowance and improve material utilization as a starting point, this paper presents a extrusion program of marine crankshaft crank, and designs related billets and dies.By finite element numerical simulation software DEFORM-3D, the extrusion process of the Marine Crankshaft crank are analyzed through three-dimensional rigid-viscoplastic thermal coupled numerical simulation. This paper analyzes the forming force, temperature, equivalent strain, the variation of metal flow.Single factor rotation method is used to analyz the die parameters and process parameters on influence law of forming force and gets the relevant parameter values under the conditions of reducing the forming force as far as possible. Extrusion process to meet the highest temperature value can not be too much and to meet Final forging temperature distribution uniform of crank arm analyzes the influence law of temperature field distribution in different extrusion speed , obtained a reasonable speed range. Research the influence law of arc string height and string elevation on crank arm in different mop coefficient are researched and shape of the end of crank arm is predicted.The stress of extrusion dies are analyzed, stress concentration area is found and analyzes the influence law of extrusion stress in different fillet radius of extrusion cavity the reasonable radius value is determined.Finally the mold strength are checked , the result shows that this designed new technology is feasible. The study of related problems has important significance for large marine crankshafts crank forging technology development .