Cellular ceramic plates with asymmetrical cell structure and manufacturing method thereof

Abstract

A method for the continuous production of a cellular ceramic plate having asymmetric cells comprising thermally treating ceramic particles and a blowing agent in a foaming furnace while conveying said ceramic particles and said blowing agent at a first speed thereby forming a cellular ceramic plate, and annealing said cellular ceramic plate in an annealing lehr by cooling it down while conveying it at a second speed, larger than said first speed, thereby stretching and cooling said cellular ceramic plate.

1 - 16 . (canceled) 
     
     
         17 . A method for the continuous production of a one-piece continuous cellular ceramic plate comprising:
 a) thermally treating ceramic particles and a blowing agent in a foaming furnace while conveying said ceramic particles and said blowing agent at a first speed thereby forming a one-piece continuous cellular ceramic plate, and   b) annealing said one-piece continuous cellular ceramic plate in an annealing lehr by cooling it down while conveying it at a second speed, larger than said first speed, thereby stretching and cooling said one-piece continuous cellular ceramic plate.   
     
     
         18 . The method according to  claim 17  wherein prior to step (b), the one-piece continuous cellular ceramic plate is transferred from said foaming furnace to said annealing via an intermediate conveyor at a third speed higher or equal to said second speed. 
     
     
         19 . The method according to  claim 17  or  18 , wherein the difference between the second speed and the first speed is 25% or less of the first speed. 
     
     
         20 . The method according to  claim 18 , wherein the difference between the third and second speed is between 0 and 10% of the first speed. 
     
     
         21 . The method according to  17 , wherein the one-piece continuous cellular ceramic plate is a one-piece continuous glass foam plate. 
     
     
         22 . An apparatus for the continuous production of a one-piece continuous cellular ceramic plate comprising:
 a) a foaming furnace arranged to treat in one continuous piece ceramic particles and a blowing agent, said foaming furnace comprising a first conveyor adapted to convey at a first speed while heating said one-piece continuous ceramic particles and said blowing agent to form a one piece continuous cellular ceramic plate, and   b) an annealing lehr arranged to anneal said one-piece continuous cellular ceramic plate by cooling it down, said annealing lehr being located downstream from said foaming furnace and comprising a second conveyor adapted to convey said one-piece continuous cellular ceramic plate at a second speed, larger than said first speed.   
     
     
         23 . The apparatus according to  claim 22  further comprising an intermediate conveyor prior to the second conveyor arranged to transfer the one-piece continuous cellular ceramic plate from said foaming furnace to said annealing lehr. 
     
     
         24 . The apparatus of  claim 23 , wherein the intermediate conveyor is adapted to convey at a third speed higher or equal to said second speed. 
     
     
         25 . The apparatus according to  claim 22 , wherein said first and second conveyors are driven in such a way that the difference between the second speed and the first speed is 25% or less of the first speed. 
     
     
         26 . The apparatus according to  claim 24  or  claim 25 , wherein the difference between the third and second speed is between 0 and 10% of the second speed. 
     
     
         27 . The apparatus according to  claim 23 , wherein the first conveyor is resistant to higher temperatures than said second conveyor. 
     
     
         28 . The apparatus according to  claim 27 , wherein the first conveyor is resistant to a temperature up to 900° C. and wherein said second conveyor is resistant to a temperature up to 600° C. 
     
     
         29 . The apparatus according to  claim 23 , wherein the intermediate conveyor comprises rolls. 
     
     
         30 . The apparatus according to  claim 23  wherein the intermediate conveyor is located at the beginning of the annealing lehr or in an intermediate lehr located between the foaming furnace and the annealing lehr. 
     
     
         31 . The apparatus according to  claim 23  wherein the intermediate conveyor is resistant to temperatures in the range 600° C.-800° C. 
     
     
         32 . A ceramic plate comprising a one piece continuous cellular ceramic plate that has been stretched whole hot and cooled in stretched condition. 
     
     
         33 . A one piece continuous cellular ceramic plate made by the process according to  claim 17 .