A lot of steel castings, especially alloy steel castings, will produce cracks during the production. That needs quality and reasonable casting process design to avoid the the problem.

Reasons for cracks are usually as follows:

1. Cooling process is too fast;

2. Section areas of steel casting parts change too suddenly, or round corners in transition part are too small;

3. The tress relief annealing was not carried out in time after cooling process;

4. Surface or internal defects.

Then let's summarize some methods to prevent the thermal cracking of steel casting parts:

1. Improve the structure of steel casting parts.
To decrease stress concentration, it is required that side wall thickness is even, transition fillet is made at corner.
 
2. Improve the melting qulity of alloy material
The oxidation inclusions and gases in the molten steel were removed by refining and gas removal process. Controlling the content of harmful impurities and adopting reasonable smelting process to prevent cold cracks.

3. Optimize the casting process

4. Aging heat treatment
Steel castings with strong casting stress should carry out timely aging heat treatment, avoiding excessive residual stresses to make castings cold cracks. When necessary, after cutting pouring riser or welding, carry out aging heat treatment once again.

CHAENG (Great Wall Steel Casting) has many years' experience in manufacturing steel casting large spare parts such as kiln tyre, girth gear, slg pot and so on. CHAENG is experienced in defect control and quality control. Welcome to consult us at any time you need.

Email: casting@chaeng.co