| 摘要 |
The improved process comprises placing in an open top, walled enclosure a pattern plate carrying the pattern for the core or mold part to be produced. The height of the pattern plate is adjustable relative to the tops of the walls of the enclosure so that when sand coated with a polymerizable resin is poured onto the top of the pattern the excess sand flows over the tops of the walls, covering the pattern with a mound of sand the slope of the walls of which is determined by the angle of least repose of the sand. A squeeze head having a surface corresponding to the surface of the pattern is now pressed downwardly onto the top of the pile of sand, to compact the sand about the pattern. While thus held by the squeeze head, material such as gas is passed from the bottom of the mold or core up through the now compacted sand, thus to polymerize the resin. The squeeze head is removed and the now cured, resin sand core or mold part is removed, ready for use in the usual way.
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