Parting surface refers to the surface where the upper and lower molds or two half molds contact. Generally, it is selected as the maximum section of large steel castings. The selection of parting surface shall ensure convenient mold lifting, simplify casting process and improve the quality of large steel castings. At the same time, the position of the parting surface shall also be subject to the selection of the pouring position, so as to avoid turning the sand mold after core closing. The selection of parting surface is equivalent to an identifier for a process scheme, so its selection standard has strict principles:
(1) Mud cores and live blocks shall be as few as possible.
(2) Try to level the parting surface to avoid hanging sand stacks on the box.
(3) All or most of the large steel castings shall be in the same half type.
(4) During pit modeling, the cavity of large steel castings shall be placed in the lower mold as far as possible.
(5) The number of parting surfaces shall be minimized.