Machining methods for large shaft forgings

The processing method of large shaft forgings in industry can be said to be relatively complex at present, and for many forging plants are direct forging processing. So, let's learn the forging of large shaft forgings.

Large shaft forgings are usually forged directly from aluminum ingots. The greater the mass of the shaft forging, the greater the tonnage of the aluminum ingot. In the casting process of aluminum ingot, the defects such as non-metallic inclusions, segregation, shrinkage holes and dense porosity are serious. In order to obtain the desired quality of shaft forgings, the internal defects of aluminum ingot are eliminated by forging. But in the actual production process, the pass rate of ultrasonic inspection of large shaft forgings is often low.

For example, in the production of the traditional forging process theory of the ordinary flat anvil long drawing process, the results of 40% of rollers are not up to the requirements of ultrasonic flaw detection because there are a lot of axial dense defects or longitudinal cracks in the center of the roller body. In addition to the defects of casting aluminum ingot, the forging process also needs to be improved. In recent years, a large number of research and simulation tests have been carried out on large forgings. It has been shown that the ordinary drawing process of flat anvil in traditional forging process theory is not ideal for the forging permeability of large forgings, which is also the main reason for the low pass rate of ultrasonic inspection of shaft forgings in large forging manufacturers.

Generally speaking, forgings are not as complex as castings, but the internal organization and mechanical properties of castings can not be compared with forgings. After heat treatment forgings, regardless of impact toughness, fracture strength, fatigue strength and other mechanical properties are overwhelming superior. Important parts are selected forging method production, its fundamental reason will be in this. This situation will continue for the foreseeable future. Especially in the new era of the twenty-first century, it should be seen that all industrial sectors will be hit by a wave of innovation, and that it will be the sectors that adopt technology that will be sustained and that there will be competition between different production processes.