Precast flue wall capping blocks are an integral part of anode baking furnace linings and therefore must meet demanding requirements, ensuring a service life that is in accordance with the longevity of other refractory materials used in these furnaces. Top blocks must have high strength, wear-, abrasion-, and thermal shock resistance and must withstand high temperatures in a reducing atmosphere. They must be dimensionally accurate and have a defined non-slip and walkable surface.
For the production of top blocks at P-D Refractories we use dense castables vibrated into moulds. Top blocks made of these materials meet the specifications for the construction of anode baking furnaces.
Besides standard cured and steel-frame protected flue wall caps, P-D Refractories offers vibrocast Top blocks using improved mixtures. These excellent new products show no decrease in strength during heating, have up to a 3x higher compressive- (MOR; HMOR) and cold crushing strength (CCS), and a generally higher abrasion resistance achieved through material composition.
The capability of firing at higher temperatures offers great advantages. After firing, the properties are stabilized, and the blocks are ready to be used. The risk of cracking due to thermal exposure is virtually eliminated. The removal of the steel frame allows the use of a higher quality raw material. By increasing the physical properties of the product, the protection of the steel frame from external unwanted forces is no longer necessary. Additionally, we were able to bond insulating material with our castable and develop our unique ThermStop concept™, which is designed to protect the block from strong thermal shocks and to keep the heat inside the flue walls, resulting in an energy saving needed to bake anodes.