Abstract: Molten metal is cast in a cavity formed within a permanent, metal mold. The major portion of the cavity is lined with a sand liner whose thickness is reversely correlated to the thickness of the integral sections of a varying thickness cast metal article. However, portions of the metal cavity are bare and such portions form a part of the interior casting surface defined by the sand liner. Thus, the cast metal contacting the bare metal portions of the mold uniformly and rapidly chills to produce harder surface areas on the finished cast article, while the remaining portions of the cast article tend to cool at a generally equalized cooling rate corresponding reversely to the thickness of the sand liner. A vacuum is applied to the casting cavity during filling with molten metal for rapidly filling the sand lined cavity and insuring complete contact between the molten metal and the bare metal portions of the casting cavity.

Abstract: A permanent casting mold has its casting cavity coated with a sand liner of varying thickness. The liner is thicker where the cast article section is thinner and the liner is thinner where the cast article section is thicker so as to permit the thicker sections to cool faster while the thinner sections cool slower. The different thicknesses of the liner are correlated so that the respective sections of the article are sufficiently cooled at about the same time for removal of the article from the mold. The mold is a cope and drag-type flask mold whose casting cavity halves are oversized relative to the cast article. The sand liner is formed therein by temporarily positioning a pattern within the permanent casting cavity halves and sand filling the space between the pattern and cavity wall. The exterior surface of the pattern corresponds to the cast surface of the article.

Abstract: A permanent casting mold has its casting cavity coated with a sand liner of varying thickness. The liner is thicker where the cast article section is thinner and the liner is thinner where the cast article section is thicker so as to permit the thicker sections to cool faster while the thinner sections cool slower. The different thicknesses of the liner are correlated so that the respective sections of the article are sufficiently cooled at about the same time for removal of the article from the mold. The mold is a cope and drag-type flask mold whose casting cavity halves are oversized relative to the cast article. The sand liner is formed therein by temporarily positioning a pattern within the permanent casting cavity halves and sand filling the space between the pattern and cavity wall. The exterior surface of the pattern corresponds to the cast surface of the article.

Abstract: A green sand mold filling system is formed of an air chamber box having a cover plate which supports a pattern. Air passageway holes, which communicate with the air chamber, extend through the plate and pattern at preselected locations, such as difficult to fill pockets, depressions and the like. An open top and bottom flask section is positioned over the plate and around the pattern. Filling sand is poured into the flask and is mechanically compacted or squeezed therein. During the filling and squeezing, a vacuum is provided in the air chamber and, therefore, through the air passageway holes, to assist the sand flow into and the sand densification at the pre-selected locations. Thereafter, the vacuum is discontinued and pressurized air is provided in the air chamber and, therefore, through the air passageway holes, to assist in separation of the compacted sand from the pattern and plate and to maintain the integrity and accuracy of the cavity formed in the sand while the flask section is removed.