| Crankshaft is one of the most important parts for engine. It will link with the role of the gas pressure in the piston into rotation of power, to pass the chassis transmission mechanism. When the crankshaft is working, it will afford the pressure of gas, inertia force and moment, the pressure is great and complex, so the crankshaft will be made a great impact of the role of alternating load. In each of the engine duty cycle, there are alternating load acting on the crankshaft through the connecting rod. Alternate the load to generate the entire crankshaft bending, torsion alternating stress, caused by fatigue crack easily, especially in the crankshaft main journals and the rod diameter at the transition fillet. In order to avoid the formation of fatigue cracks on the crankshaft fillet groove required for strengthening. Groove reinforcement is including nitrification, shot pellet, induction hardening, fillet rolling, etc. One of the most effective way to cut the fillet is rolling and induction hardening, and it is also commonly used domestic engine manufacturing enterprises enhanced mode. Fillet Rolling Strengthening pollution due to small, low energy consumption, quality control is convenient, has gradually become the mainstream of strengthening the engine crankshaft by Germany HEGENSCHEDT's determination of ductile iron crankshaft rolling can be increased to 280% after the life, After rolling steel crankshaft life can be increased to 237%.My company's engine is the introduction of Japan's Mitsubishi Motors 4G6 technology, the existing crankshaft production line introduced in 1999, Deep cutting groove roll fillet with HEGENSCHEIDT-MFD AUTOMATIC 7812K rolling machines, In this paper, with the device as a test machine, using finite element method, using ANSYS software, the operating conditions of the crankshaft of the mechanical analysis and the rolling simulation, and after the actual verification, and achieved good results on the future of cast iron crankshaft The adoption and roll handling of the issue and provided a reliable basis. In this paper, fillet rolling process carried out the following studies:1) On the basics of Strengthening Mechanism of rolling in the right corner based, we point that the key parameters of affecting the fatigue life is roller pressure, that pointed out the direction for process research.2) We take the dynamics research in Crank-connecting rod mechanism and find the greatest force the crankshaft position.In accordance with the instantaneous cylinder pressure, We calculate the resultant force of the rod could be afforded. By the analysis of the ANSYS software (static and harmony response analysis module), solve out the operating conditions the maximum tensile stress and its location, the post-sequencing analysis of residual compressive stress to provide reference. At the same time, through the qualitative analysis of the engine operating conditions that inotropic rolling rod diameter causes.3) On the basic of rolling deformation and pulling and distribution of pulling and returning force, find out the scope of limit load for the rolling simulation analysis and on-site roll and provide a theoretical basis for the determination of the pressure.4) Working condition by rolling over the static load-step analysis, obtained:With the increase in the pressure roll, pressing the amount of residual stress and its non-linear increase. Thus infer that when the pressure reaches a certain value, the residual stress are not increased. Selected for on-site roll pressure to provide a basis.5) Put the simulation data in the processing of verification, according to fatigue test results, the selected pressure range rolling, and rolling through on-site device hardware to solve the partial adjustment of the pressure rise caused by bending problem; through the process before the size of the adjustment process to address the increase the problem of axial elongation. |
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