Research status of driven helical gear blank of automobile rear axle

At present, the better process methods for producing the driven helical gear blank of automobile rear axle at home and abroad are air hammer blank making and ring rolling machine forming, and the material saving effect of this method is particularly prominent. Rolling process is a continuous forming technology that adopts local pressure and realizes overall deformation through deformation accumulation. The deformation force applied to the workpiece by rolling is very small. Compared with the existing forging process of helical gear blank, rolling can eliminate vibration and noise and improve the working environment of workers. Taking the driven helical gear of automobile rear axle as an example, the rolling forming is compared with die forging, and the five characteristics of rolling forming are summarized, that is, not only the requirements of equipment tonnage are low, but also the utilization rate of materials is high, not only the internal quality is excellent, but also the working conditions are much better, and the production efficiency is also improved. A new type of forging die is presented. The die core and die structure can float. The forgings are formed in a closed annular die cavity. The forgings produced by the new forging die have no flash, the mass of blocks is reduced, and the production cost is significantly reduced.

The main innovation of the new die forging is that it overcomes a defect of closed die forging, that is, when the blank enters the lower die, with the increase of friction, the material flow is difficult and it is easy to form the defect of insufficient filling. In addition, for the production of bad forging die of helical gear, there are longitudinal flash in the inner hole of forging, which is difficult to remove and hinders the subsequent processing. The process optimization of driven helical gear blank is given in the literature. The driven helical gear blank is formed by rolling first, and then refined by double cone roll rotary rolling process. This process greatly improves the machining efficiency on the premise of ensuring the quality. A forming production line of driven helical gear is introduced. The document points out that there are many shortcomings in the blank forming of driven helical gear in China. The forging hammer pre forging is the forming of striking force, with high vibration and noise and poor working environment; In view of the shortcomings of the above technology, a production line for the blank forming of driven helical gear of automobile rear axle is proposed. The production line has the advantages of high production efficiency, good labor environment, no vibration and low noise, which can effectively eliminate the defects of forgings.

This paper mainly discusses the rolling forming process of helical gear blank of automobile rear axle, studies and analyzes the deformation characteristics of rolling of stepped hole shaped parts, obtains the basic calculation basis of rolling forming preform design and rolling die design, and puts forward the method of eliminating the defects of rolling forgings by using closed pass, which can effectively limit the circumferential metal flow, ensure the axial size of forgings, and prevent end face pits, burrs and other defects. This paper expounds the new rolling process of closed pass large helical gear blank forging, gives the die design and calculation formula of closed pass rolling ring, and designs the mathematical model of rolling forming of rear axle driven helical gear blank, which improves the dimensional accuracy and ensures the blank quality. In the literature, the upsetting of the blank of the driven helical gear of the automobile rear axle is simulated and optimized, and the effect of temperature on the plastic deformation is analyzed. If the temperature is too high, the blank will be burned, and if the temperature is too low, the tonnage of the required equipment will increase accordingly. The reasonable taper of upsetting upper die is also obtained, which improves the mechanical properties of upsetting parts. This paper analyzes the causes of flash caused by the ring rolling forming process of helical gear blank, and puts forward the methods of increasing the reaming step, expanding the inner hole and finishing the blank after ring rolling to improve the blank accuracy, so as to reduce the subsequent machining workload and improve the production efficiency.

This paper introduces a new method of sleeve forging small gear blank when die forging large gear blank. This design is very ingenious, which can not only save metal and reduce waste, but also improve the metal flow state of the punching skin of large gear blank, significantly reduce the die forging force, and then improve the service life of the die. The multi-step closed die forging process on the hot die forging press of helical gear blank is designed. In the die design of helical gear blank, the multi-step numerical simulation technology is applied to simulate the metal flow state, predict the specific location of defects, and guide the closed die forging process design of axisymmetric forgings with blind holes.

The picture shows the driven helical gear blank of automobile rear axle produced by ZHY Gear.

Scroll to Top