大型铸铁砂箱在使用过程中四个弯角处容易发生断裂。这是因为铸铁砂箱在铸造后一般都不经热处理即投入使用,砂箱在弯角处存在着较大的铸造应力。在烘干砂型和浇注铸件时,砂箱受热不均衡,因而发生不均匀的变形。在吊装、摆放和落砂时有时不能平稳,砂箱弯角处又受到较大的扭矩。 Large cast iron sand box in the process of bending at four corners prone to fracture. This is because the cast iron sandbox is generally put into use without heat treatment after casting, and the sandbox has large casting stress at the corner. In the drying of sand casting and castings, the flask is heated unevenly, and thus uneven deformation occurs. In the hoisting, placing and falling sand sometimes can not be smooth, sandbox corners have been subject to greater torque.