|Coatings for sand molds and cores|
Foseco’s sand mold and core coating products help foundry operators achieve the best available casting surface finishes at the highest possible level of operational efficiency. Because we focus our efforts on advanced rheology and suspension technologies, and use only the highest quality refractory components, Foseco’s sand coating products provide “as-cast” excellent surface performance, particularly in critical applications. They are also noted in the industry for their ease of use and process productivity.
Foseco’s Sand Coating products provide:
• Reduced defects, particularly sand burn-in.
• Increased productivity, because Foseco’s pioneering work in coating rheology and suspension technologies allows full-rate production of castings, minimizing coated core scrap and rectification, coating process variation and handling slow-downs.
• Improved quality, in addition to reducing defects, by acting as a robust element in a consistent foundry process
Refractory coatings provide a protective barrier between the molten metal and the mold or core substrate. This barrier is of paramount importance in ensuring the integrity of the as-cast surface of the finished component. Inconsistencies within the coating structure or the application method will be reflected in the surface quality of the component.
The improvement in as-cast surface finish can be as basic as the removal of sand grain definition, but more often it is the reduction and elimination of a number of casting defects:
• Metal Penetration
• Poor Casting Strip
• Mold Erosion
• Metal / Mold Reactions
By careful selection of refractory fillers and rheology, Foseco coatings are designed to deposit the correct coating structure onto a given substrate, to ensure cast surface integrity and the application characteristics required by the foundry. The range of products have been specifically engineered so that they can be applied by dipping, flow coating, brushing, swabbing and spraying.
It is frequently possible to produce good surface finish on highly cored aluminum castings prepared in sand moulds without the need for a refractory coating. Nevertheless, problems can occur and Foseco supplies a range of products to address these.
Refractory combinations are chosen to provide optimum protection for specific casting conditions, while maintaining a cost effective solution. The section thickness of the casting is a good measure of the casting conditions that will prevail and the type of casting defects which the coating must overcome. By ensuring the correct refractory combination, complemented by optimised application rheology, casting defects are minimised and surface integrity is ensured.
HOLCOTE water based coatings
HOLCOTE products are water based coatings with a full range of application rheologies and refractory combinations that offer superior performance for individual foundry requirements. Applicable to both sand molds and cores and generally oven dried.
ISOMOL solvent based coatings
ISOLMOL products are solvent based coatings with a full range of application rheologies and refractory combinations that offer superior performance for individual foundry requirements. Applicable to both sand molds and cores and generally air or flash dried.