| 摘要 |
A method of making resin bonded sand cores using heat activated catalysts comprising: providing a core box having (i) a thermally conductive cope and drag resiliently sealingly mating at essentially a horizontal parting plane, and (ii) core defining walls enclosing an interior and perforated by sand-filtered ports; blowing a sand, resin and liquid catalyst mixture into said interior to form a sand body; conductively heating at least the outer skin of said sand body to a first temperature (i.e., 300-400.degree.F); and essentially simultaneously with said conductive heating, convectively heating (in two stages) the remainder of said sand body by flowing a heated gas therethrough at a second temperature lower than said first temperature (i.e., 250-290.degree.F), said heated gas entering said sand body from the drag and exiting said sand body by way of said cope.
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