Study On The Upsetting Theory And Experiment Of The Full Fabric Crankshaft Formed By Bare Rod Blank

Crank shaft is widely used on the combustion engine of engine and ship , one of main parts of combustion engine . The high requirements are needed for crank shaft from the property of amount and quality with rapid increase of national economic and needs of national defence modernization construction .Otherwise, the RR method of bending upsetting process for producing full fabric crankshaft needs stepped shaft blank and the forming technique falls behind in our country now, especially this method can not use the material of crankshaft forge pieces fully.This situation does not fall behind the manufacturing level of the foreign peer only ,and this can not meet the requirements of domestic crankshaft. So that we do the research on the forge technique to full fabric crankshaft has the actual meaning.This paper takes 12V240 crankshaft as study subject, and analyses the problems that outer metal of the upper corner of crankshaft can not fill fully,the process redundancy of forge is big and the material usage is low to the crankshaft RR method of bending upsetting technique using Deform-3D . At the same time we adopt the three steps method of pre-upset—staggered forging—finish-forging , and make the simulation analysis for metal flow pricinple during crank throw deformation, analysing the reasons of profiling defect .We find the first upsetting ratio and misforging angle are the main technological parameters controlling the forming of the corner,according the horizontal upset and vertical displacement are the two independent deformation patterns.We solve the problem of the fabric of stepped shaft is cut off to realize the fibrous completeness better by increasing the step of pre-upset and using bare blank. We optimize the blank and container shape based on this , puting forward a accurate forming processing program for full fabric crankshaft formed by bare shaft blank.This program can easily control forming, and save material greatly,for example 12V240 crankshaft can save 34% comparing the conventional RR upsetting and forging method.The paper furtherly researches on the simulation experiment principle and conceptual design by 1:3 scale , taking Pb as material.Pb is carried out compression test under normal temperature on Gleeble-1500D thermodynamic simulation test machine and we get Pb relation between stress and strain under different deformation conditions, then do the simulation analysis to the simulation experiment model using the finite-element method for determining the technological parameters of first upsetting ratio, misforging angle and so on , analyzing the forming of crankshaft and the stress of die. We use double direction hydraulic press machine (5000KN) in Taiyuan technology university , taking Pb as material, making a accurate forging test for 12V240 crank shaft , based on bare shaft blank full fabric crank shaft . Validate the correction of process analysis and finite element simulation .