METAL PART FOR PRODUCING MINERAL WOOL AND OTHER PRODUCTS MADE OF MINERAL MATERIAL, SPINNING SPINDLE FOR PRODUCING MINERAL WOOL BY CENTRIFUGING MOLTEN MINERAL MATERIAL AND METHOD OF MAKING SUCH METAL PART

摘要

A metal component like a spinner for producing mineral wool material consists of or at least comprises a unitary cast piece of metal superalloy preferably on the basis of nickel or cobalt, which unitary cast piece is in the form of a single crystal. The component may be produced in a receptacle (11) consisting of a lower crystal forming chamber (12) and an upper workpiece forming chamber (15) connected by a single crystal selecting constriction (16), or starter, so as, in combination with suitable heating means (20) and drawing speed, to allow drawing of a single crystal to form all of the unitary cast workpiece in the cavity (19) of the mould or receptacle (11). The single crystal is significantly more corrosion resistant than the same material of poly-crystal structure. The capability of sustaining higher strain at high temperature before creep rupture after 1000 h on the one hand, and the high ductility leading to a more even stress distribution within the material and avoiding stress peaks on the other hand cooperate to make a spinner of the invention best suited for operation at high temperatures as they are preferred in the fiberization of rock wool like basalt by internal centrifugation.