Flaring deformation: the forming reason is in the opening size of sand core and sand mold hindered the contraction of the casting, plastic deformation in the casting mouth free structural part, resulting in a flaring deformation defects. Warping deformation: deoxidization casting occurs at both ends or one end even after the outer edges buckling deformation, castings under central sunken, leads to uneven castings, this form of deformation is called buckling deformation.Its forming reason is: because the casting cooling, or uneven thickness, thickness of the casting temperature difference, each part of the casting cooling speed is different, produce the uneven plastic deformation, lead to form the warping deformation.