METHOD AND MANUFACTURING OF MOULDING SAND, SUCH MOULDING SAND AND APPLICATION THEREOF

摘要

A moudling sand, produced from free and mainly pure quartz sand particles, mixed with free and mainly pure feldspar particles in the amount of 5 to 20 percent by weight, is well suited for use in the production of iron castings in which blatribs must be avoided. The amount of free feldspar particles creates a buffer which allows the quartz sand particles to perform an expansion without any risk of formations of cracks in the sand. Furthermore, the produced moulding sand will have a good binding so that there is no risk that edges are broken off from cores or moulds at ingates.