Large alloy steel castings are easy to have problems (the more common problems are cracks) in casting process if they are incorrect or improper in operation.
Large steel castings are crack due to the surface or internal defections; the cooling rate is too fast when pouring and cooling process;it doesn’t stress annealing in time after pouring and cooling ; alloy steel casting section changes suddenly, or over parts of fillet is too small.
To prevent these problems, we need to improve the structure of alloy steel castings and the melting quality of alloy materials, adopt the correct alloy steel casting process measures, and carry out aging heat treatment. The simultaneous solidification of alloy steel castings not only helps to prevent hot cracks in alloy steel castings, but also helps to prevent cold cracks in alloy steel castings. The location and size of the alloy steel casting and riser of the alloy steel castings are reasonably set, so that the cooling rate of each part of the alloy steel castings can be uniformly reduced, and the cold crack tendency of the alloy steel castings is reduced. Prolonging the residence time of the alloy steel castings in the mold, so as to avoid the larger internal stress in the alloy steel castings prematurely and to produce cold cracks. In short, to cast the large alloy steel castings carefully and will have the perfect alloy steel castings.