The chain rail link is an important part of the excavator. It is because of the existence of the link that the huge excavator can "walk". As long as the excavator chain rail link in the running problems, then the entire excavator operation will be very difficult. Therefore, the quality of chain rail link directly affects the use of excavator.
So how is such an important link produced? At present, there are two main processes to produce the link, one is casting and the other is forging.
The casting process of chain rail link is to melt the material into liquid state, then pour it into the mold cavity with the shape of chain rail link, and wait for its solidification to form a complete chain rail link. However, the high temperature of casting workshop and the melting of materials are easy to produce waste smoke, which not only affects the health of employees, but also pollutes the environment. The cast chain rail link also has the problems of loose structure, coarse grain, and easy to produce shrinkage cavity, shrinkage porosity and air hole. At the same time, the hardness and wear resistance of the cast chain link are relatively poor. If you want to increase the hardness and wear resistance, you need to add chromium (CR) element, but the price of chromium is very high, adding chromium will increase the cost of spanner. The above reasons make the cast chain rail link in the market has been declining year by year.
The forging process of chain rail link is to heat the bar, and then put it on the die of NC die forging hammer for forging. After initial forging and precision forging, it can be directly forged. The speed of CNC die forging hammer is fast, and the shape variable of the chain rail is high, which can change the internal structure of the chain rail link and increase the forging density. It will not produce loose structure and coarse grain, and the problems such as shrinkage cavity, shrinkage porosity and air hole are easy to occur inside. Therefore, the hardness and wear resistance of the chain rail link forged with CNC die forging hammer are higher.