High density, clay-bonded, isostatically pressed ValuStar crucibles contain high graphite and silicon-carbide content.
Robin White, general manager at Molten Metal Systems, says: “We’re confident that ValuStar crucibles will add huge value to the aluminium casting industry by reducing downtime and maintenance, therefore increasing productivity. They’ve been developed to resist oxidation, which is a common challenge for operators in modern foundries and cast houses. We’ve rigorously tested them against other crucibles in similar operating conditions, and ValuStar has shown that it has a significantly longer lifetime than all other isostatically pressed crucibles in low-temperature applications.”
To demonstrate the difference, Morgan tested the ValuStar in a 24-hour aluminium melting and holding application, against a conventional isostatically pressed crucible. The latter needed to be replaced after eight months due to a reduction in thermal conductivity and cracking of the top brim as a result of oxidation.
Meanwhile, the BNS 200 ValuStar crucible’s lifetime was 14 months, exceeding the conventional crucible’s service life by 75% in similar conditions. As well as extended life, thermal productivity was improved by 24%.
As a point of note, both crucibles were split in half for analysis. While the conventional crucible showed brim oxidation and oxidation nests, ValuStar only showed slight brim oxidation, which was caused by the insulation fibre.