Developing of Ceramic Roof Tiles Process by Powder Pressing and Firing in Roller Kiln

摘要

In this work, it was investigated the behavior of a ceramic composition in pressing and firing process, related to its pyroplasticity, to permit the production of roof tiles in roller kiln. Experiments were realized varying the parameters of pressing, sintering and composition, adding a refractory material. With this study, it became possible to select the optimal parameters of pressing and firing, and to start the pilot industrial tests. The developed process has advantages, in the process and the final product, related with the standard process (extrusion and firing in tunnel kiln). The process is energetically more efficient, because there are no movable in the kiln. It was measured a flexural strength above 40 MPa with 12mm thickness, saving material. Also, the product has a higher quality in size, shape and dimensional precision (linear thermal shrinkage lower than 1,5%); tonality, porosity (water absorption lower than 10%), and frost resistance.