Spiral gears include spiral cylindrical gear and spiral bevel gear. As one of the most basic parts to transmit motion and power, it is widely used in the industrial field. With the rapid development of China’s automobile, aerospace and aviation industries, the demand for gears is increasing, and higher requirements are put forward for the variety, specification, accuracy, strength and cost of spiral gears.
At present, the production process of spiral gear is still cutting. The traditional cutting process is to select forging blank when the diameter of bar blank is large, and form it through multiple processes such as turning end face, drilling, turning inner and outer circle, gear hobbing, gear shaving and heat treatment. This method has long processing cycle, low production efficiency and waste of raw materials. During processing, the metal fiber in the tooth shape is cut off, so that the strength of spiral gear is not high, Affect its bearing capacity. Therefore, there is an urgent need for a new spiral gear production process with high quality, high efficiency, material saving and energy saving.
At present, industrial technology aiming at net forming and near net forming has developed rapidly and played an important role in industrial developed countries. Precision forging technology has achieved near net shape to a great extent, that is, to manufacture workpiece blanks close to the shape of parts. Compared with traditional forming technology, it reduces the cutting amount of post process and reduces the consumption of materials and energy. Its development trend is to realize net forming, that is, directly make the workpiece that meets the shape requirements.
Precision forging process is one of the main processes of spiral gear net forming. The production of spiral gear by precision forging process not only has the significant advantages of material saving, energy saving, low cost and high efficiency, but also helps to form a dense and uniform material structure in the spiral gear, have continuous and reasonable metal streamline along the tooth profile, and form a surface work hardening layer and smooth transition tooth root, so as to greatly improve the wear resistance, corrosion resistance and bending strength of the root of the spiral gear, Obviously improve the fatigue performance of spiral gear. However, as far as the precision forming of spiral gear is concerned, especially the precision forming of spiral gear, due to the complex geometry of parts, many influencing factors, forming difficulty, and the research on the forming law is relatively weak, the spiral gear teeth are helical, and its demoulding is difficult. Therefore, the precision forming technology of spiral gear is being paid more and more attention by researchers all over the world, and has become one of the key research topics in the field of plastic machining.
In recent years, with the rapid development of computer software and hardware technology, metal plastic flow theory and computer graphics, finite element numerical simulation technology has developed rapidly. Using advanced methods such as numerical simulation to solve practical problems in industrial production has become the development direction of metal forming technology. Using the finite element numerical simulation method, the simulation analysis of the precision forging process of spiral gear can be realized, the precision forging law of spiral gear can be obtained, and the optimal and feasible design scheme can be found in a short time at a small cost, so as to provide technical basis and theoretical guidance for the research and application of precision forging process of spiral gear.