A molten metal filter includes a refractory plate having an opening therethrough. A refractory filter element is attached to the refractory plate and projects therefrom, the exterior surfaces of the filter element generally defining a rectangular prism. The filter element is hollow so as to define an...http://www.google.fr/patents/US5126047?utm_source=gb-gplus-shareBrevet US5126047 - Molten metal filter
