The elimination of anti-veining sand additives through the use of active ingredient absorption coatings

摘要

From a worldwide perspective, silica sand is the preferred medium for the manufacture of moulds and cores to be used for the casting of liquid metal, due to its availability, cost and compatibility with most foundry binder systems. Since the introduction of the amine-catalysed polyurethane coldbox (PUCB) process in the late 1960's its usage has grown to the point where it has become the dominant process globally for the bonding of silica sand to produce cores for high production iron foundries. The combination of silica sand and PUCB binders provides a cost-effective process for the manufacture of high strength cores with intricate geometry at high production rates and during the casting process dimensional accuracy is maintained and the cores are relatively easily removed after the metal has solidified.