Digital Research On Forming Of (6026) Connecting Rod

Connecting rod is an important component of the engine. It works in a complex operating conduction, which means that the performance of the connecting rod must meet the high demand. In recent years, the automobile manufacturing industry in domestic has developed rapidly, gasoline engines have been increasingly demanded and the market for high-quality connecting rod is also growing. Metal plastic deformation can be affected by many factors. However, the current theory is not mature enough. Therefore, production mainly relies on the experience of technical personnel to trial and repair mode in the factory, which leads to the low quality and efficiency of the forming.In this paper, the 6026 connecting rod, coming from a forging company in Jinan, is researched. The goal of this paper is to enhance the quality of the mold and increase the material utilization based on the actual situation of the company.The forging process of 6026 connecting rod consists of roll forging and hot forging. In the product design, the forging drawing is designed in accordance with part drawing, the final forging die is evaluated by the forging drawing, and the preforging die and bending die are designed on basis of experience. The blank at the beginning of the hot forging process is also designed based on experience. Roll forging billet is the end product of roll forging process as well as the blank at the beginning of the hot forging process. Then hot forging process is simulated by numerical analysis with the roll forging billet for the initial blank. Preforging die, bending die and roll forging billet are optimized by the analysis results. Cutting size of the original blank is calculated by roll forging billet optimized. Finally, based on the original blank and roll forging billet optimized, the roll forging mold cavity can be further optimized through numerical simulation. In the end, the roll forging mold obtained will have better forming quality.In the hot forging process, the 6026 connecting rod’s cold and hot forging drawings are designed according to its parts drawing, final forging die, preforging die and bending die are designed combining with the hot forging press die design principles. Their three-dimensional models are completed in NX. The roll forging billet is the blank at the beginning of the hot forging process, it’s designed based on experience in line with the feature segment correspondence principle, hot forging process is simulated using the software of Deform, the blank deformation is analyzed. According to the deformation characteristics and point tracking method, the defects of the initial model are found. Then the model is modified, and the numerical simulation analysis is launched repeatedly for its further improvement, eventually, the optimized roll forging billet can be obtained, the cutting size is φ70×160mm, which is calculated based on the optimized roll forging billet.In the roll forging process, the way of feeding is intermediate biting, and the calculated roll forging processes are four passes. Besides, the groove system of the roll forging die cavities is oval-round-oval-round. Based on the blanking dimensions calculated, the roll forging drawings are determined. Then, on the basis of the roll forging drawings, die cavities are designed, the external dimensions of dies are calculated, and by using Table-Driven method, the parametric models are accomplished in NX. The whole rolling forging process are simulated by the software of Deform. Analyzing the diagrams of stress, strain and load stroke obtained from the simulation, defects can be found in the locking forward slip zones, backward slip zones and the fillet area in the transition zones. Then the design of roll forging die cavities can be modified. The simulation analysis and model modification process are launched repeatedly, until the roll forging mold which have better forming quality are obtained.Verified by practical production, the forming quality of roll forging die, bending die, preforging die and forging die can satisfy the production requirements. The project greatly shorten the mold design cycle, and comparing with the blanking method adopted before, the blanking of single-piece lose about 300g of billet weighing, material utilization increases from 75% to 80%. According to the annual production of 6026 connecting rod is two hundred thousand, forging materials saved annually for the enterprise can be more than 60 tons, which brings about prominent economic benefits.