07 Jun 2022 UTC+8Views:
Crack defects occur in the production of many steel castings, especially alloy steel castings. Generally, there are many reasons for cracks:
1. The cooling speed is too fast during the casting cooling process
2. The change of the section of the casting is too sudden, or the fillet of the excessive part is too small
3. Stress relief annealing was not carried out in time after pouring and cooling
4. There are many surface or internal defects
1. Improve the casting structure
The wall thickness should be uniform, and the corners should be rounded to reduce stress concentration. The spokes of wheel castings can be bent if necessary.
2. Improve the melting quality of alloy materials
Refining and primary processes are used to remove oxide inclusions and gases in the metal industry. Control the content of harmful impurities and adopt a reasonable smelting process to prevent cold cracks.
3. Adopting correct casting process measures to gradually achieve simultaneous solidification during the casting process is not only beneficial to preventing hot cracks but also helps to prevent cold cracks.
4. Aging heat treatment
Castings with large casting stress should be subjected to aging heat treatment in time to avoid excessive residual stress-causing cold cracks in the castings. If necessary, gradually after cutting the riser or jersey, heat treatment with this aging is also carried out.
As a professional large steel casting manufacturer, Xinxiang Great Wall Casting (CHAENG) has advanced technology and rich experience in heavy steel castings. At present, it has the ability to provide users with a series of services from blank casting to finished products and the processing of key components and finished products.