Foundries and designers often dream about being able to convert fabrications to castings or expand sales and marketing by developing new product based on designs that employ castings. In some cases they are successful. In other cases, existing casting technology will not provide an easy or economical vehicle to allow articles to be produced using the existing casting methods. Those new products that can be designed from scratch or converted from fabrications improve the metal caster's ability to fill his facility to capacity, and, ultimately, result in increased sales, profits and return on investment. Advances in casting technology are primarily the result of identifying the need to find alternative solutions to technological problems associated with current levels of production. Often it is the case that designers select the casting process based upon the current level of capability. In some cases, the products desired can not be produced with existing technology and the opportunity to expand the use of castings in saleable products is compromised and the product produced by fabrication or alternative materials are chosen over castings. This paper describes the technical limitations of existing molding processes used to produce steel casting and offers a potential solution to thin wall casting production through the introduction of a molding media that employs the use of preheated molds. Details associated with the mechanics, the materials and the process are reviewed to provide the reader with a better understanding of the thermodynamics and the properties associated with pouring molten metal into room temperature molds vs. preheated molds. In addition to the general properties or benefits offered by high temperature molds, process variables such as mold preparation, treatment, gating and risering parameters will be described in detail to provide the reader a better understanding of the technology associated with converting resin bonded molds to inorganic bonded molds and cores that are capable of producing castings with section sizes under 2mm.
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