Pre-forming and Forming Process of Forging Train Wheels
Views: 24 Author: Site Editor Publish Time: 2020-06-03 Origin: Site
Today we take a look at the preforming and forming process of train wheel forging. Among them, the forming process of train wheel forgings is the key process for matching the rolling capacity of thermoforming units. A reasonable and scientific forming process must not only ensure that the pressure limit value of the press meets the preset process value, but also meets the rolling capacity requirements of the rolling mill in the next process.
1. Pre-forming technology for train wheel forgings
The blanks of the hot wheels are cast using cylindrical steel billets with a diameter between 380mm-406mm. A high-speed sawing machine is used to cut the steel billet into sections. After the sectioned billets are heated, a manipulator grips and feeds them to the press to perform the preforming process. In the pre-forming process, the upper grinding tool uses a forming die, and the lower die uses a centrally protruding indentation die to achieve the metal volume distribution to the rim and hub.
The die forging process of the press uses static pressure forging, and the entire forging process is completed in one stroke. The excellent pre-forming technology for train wheels not only ensures the initial shape of the train wheels, but also plays a dual role in improving the internal structure of the train wheels and the metal flow lines. However, if the process at this stage is unreasonable, it will directly lead to defects such as eccentricity and incomplete filling of the train wheels. It will bring difficulties to the operation in the subsequent processing stage, and it will directly lead to the scrapping of the train wheels.
2. Forming process of train wheel forgings
In the forming stage of the train wheel forgings, the shape of the hub and the pressed web are mainly obtained, and the forming of the main parts of the rim is completed at the same time. The process is typical of open flashless forging. After the die is pressed, the first thing to be pressed is the spoke of the train wheel. The inner metal of the train wheel is subjected to the force from the central punch to drive the outer metal to flow in the horizontal direction. With the sharp increase in the amount of depression, the outermost metal of the wheel blank contacts the inner wall of the forming die.
Under the joint action of the center punch and the inner wall of the forming die, the metal in the wheel blank forms a split surface, which flows to the hub and the lower side of the rim and the upper side of the rim, respectively. In this process, the underfill of the rim is optimal. In addition, due to the different height of the mold cavity in this process, the metal deformation in different parts of the wheel blank is directly different. The deformation at the spoke is the most prominent, while the deformation at the rim is the smallest.
