What is the parting surface in the mold with the largest product projection area? Too abstract. Who can tell me about it?

When designing a casting mold, there should be a parting surface, which refers to the joint surface between mold parts. When selecting the parting surface, it should be: 1. The parting surface should have the largest horizontal projection size; 2. Try to meet the requirements of pouring position; 3. It should be convenient to draw the mold and simplify the molding process. 4. The parting surface should be as flat as possible, and no or less curved surfaces should be used; 5. The number of parting surfaces should be as small as possible; 6. As far as possible, the parting surface should make the important surface and datum plane of the whole casting or casting in the same part of the mold (preferably the lower part). Wait a minute. Product projection area: refers to the projection area obtained by projecting the casting onto the parting surface with the parting surface as the projection surface. Should be maximized. Because the mold should be taken out to form the cavity before casting, the largest surface should be taken as the parting surface before taking out the model.