MPR Refractories Ltd. Manufactures Fire Clay High Alumina Insulating Castables. MPR Refractories Ltd. Is an ISO 9001:2008 certified company. MPR Refractories Ltd. Offers Slide Gate Plates, Collector Nozzles, Ladle Nozzles, Porous Plugs, Tundish Nozzles, Well Block for Porous Plugs, 90 K Mortar, 95 H Castable, Tundish Boards, Packing & Sealing Compounds, etc. The Fire Clay High Alumina Insulating Castables of model number MPR insulcast 8S are used in heaters, stacks duct in petroleum applications.