High Intensity Slender Bolt Rod Cold Drawing, Rolling Forming Technology Methods, Parameters, Tests And Studies

The topic originates from the actual production of Guizhou high strength bolt factory. The study is based that the modeling craft methods of the high strength slender waist bolt apply difficultly and its manufacture surface quality is not well on this condition of the normal manufacture temperature. With researching in Guizhou high strength bolt factory and standard accessory manufacture limited liability corporation of Chinese aviation industry, we find out that automobile industry and aviation industry and navigation industry are widely applied in the high strength slender waist bolt. Engineering technician always have used cold upsetting craft or second cutting craft to machine accessory, those leads to the results that the fatingue strength of bolt decreases in the manufacture process and they are not contented with high quality accessory demand in mechanical application domain.The thesis mainly summarizes that those are the theoretic feasibility of cold tension-rolling modeling craft to high strength slender waist bolt, the development of rolling modeling technology at home and abroad, the characteristic of rolling technology, the development of finite element analysis method, the theoretic of nonlinear finite element, the relation of stress and strain, the method of copying with increment, the method of finite element difference, copying with contact problem, the result of nonlinear problem and the strengthening rule of material plastic deformation. We put forward tow efficacious project about rolling wheels of rolling equipment, and analyze their advantage and disadvantage, and certain the second project to be this thesis research project, Mastering the configuration and characteristic of ADINA, and unifying physics quantum unit, we use computer to establish the rolling models, to define materials, to create meshes, to fix boundary conditions to apply loads, define time functions and time steps and to simulate the rolling process. We impose different craft parameters to simulate the tension-rolling modeling process, while comparing with other project to attain maximum or minimum, and analyze which parameters can bring out more effect to the bolt capability and to the manufacture surface quality.We can put out these results with finite element simulation analysis and test results analysis: the material deformation resistance counteracts its plastic deformation. The deformation resistance is more, the plastic deformation is more difficult coming true. The rolling accessory is applied axial force, at the same time, the rolling wheels apply radial extrusion, the results are brought out that the material is at three orientation strain condition, altering rolling accessory stress-strain condition, decreasing material deformation resistance, increasing material fluxion capability and coming true easily plastic deformation. Comparing with the first scheme, the second scheme is more universal, is smaller relative rolling measure, is more rolling times, is better surface quality of rolling accessory, is smaller plastic deformation, is smaller deformation resistance and its maximum strain is about 82.7% of the first scheme's and its efficacious strain is about 86.6% of the first scheme's. The rolling accessory plastic deformation capability is well, the rolling accessory plastic deformation comes true easily, the effect of cold tension-rolling modeling is preferable, while the rolling accessory applied axial force and radial displacement are being appropriate value. The modeling effect is preferable and the rolling modeling comes true easily, when the rolling accessory axial force is about 80% of material submission limit and radial displacement per rotating half circuit is 0.05 millimeter. With the axial force being a appropriate value, the maximum area shrink rate exceed 57.76% in actual rolling test and attain well surface quality, and the maximum area shrink rate reach 72.25% too in computer simulation analysis.ADINA simulating result is propitious to recognizing those factors affecting high strength slender bolt modeling craft, and provide parameter foundations to simple rationally manufacture process and to produce rolling equipment.