Melt-Formed Inorganic Fibres

Abstract

A needled blanket is provided comprising melt-formed inorganic fibres having an overall composition in weight percent SiO 2 : 47 to 65%; AI 2 O 3 : 35 to 53%; the blanket having • a shot content, of shot >45 μm, of less than 51 wt %, • a specific surface area [BET)>0.25 m 2 ·g −1 . also disclosed are fibres for producing such blankets, and self-supporting products made from such fibres.

1 . A needled blanket comprising melt-formed inorganic fibres having an overall composition in weight percent
 SiO 2 : 47 to 65%   Al 2 O 3 : 35 to 53%   
       the needled blanket having
 a shot content, of shot >45 μm, of less than 51 wt %, 
 a specific surface area (BET)>0.25 m 2 ·g −1 . 
 
     
     
         2 . A needled blanket as claimed in  claim 1 , in which the amount of SiO 2  is greater than 52%. 
     
     
         3 . A needled blanket as claimed in  claim 2 , in which the amount of SiO 2  is greater than 53%. 
     
     
         4 . A needled blanket as claimed in  claim 3 , in which the amount of SiO 2  is greater than 54%. 
     
     
         5 . A needled blanket as claimed in  claim 4 , in which the amount of SiO 2  is greater than 55%. 
     
     
         6 . A needled blanket as claimed in  claim 5 , in which the amount of SiO 2  is greater than 56%. 
     
     
         7 . A needled blanket as claimed in  claim 6 , in which the amount of SiO 2  is greater than 57%. 
     
     
         8 . A needled blanket as claimed in  claim 1  in which
 SiO 2 +Al 2 O 3 >98%. 
 
     
     
         9 . A needled blanket as claimed in  claim 1  having a shot content of less than 45 wt % or less than 44 wt % or less than 43 wt %. 
     
     
         10 . A needled blanket as claimed in  claim 1 , in which the needled blanket has a tensile strength to density ratio of >0.39 kPa/kg·m −3  or >0.43 kPa/kg·m −3  or >0.45 kPa/kg·m 3 . 
     
     
         11 . A needled blanket as claimed in  claim 1 , in which the specific surface area is in excess of 0.3 m 2 ·g. 
     
     
         12 . A needled blanket as claimed in  claim 1 , in which the inorganic fibres have an arithmetic mean diameter <2.5 μm. 
     
     
         13 . A needled blanket as claimed in  claim 1 , in which the inorganic fibres have an arithmetic mean diameter <2.25 μm. 
     
     
         14 . A mass of melt-formed inorganic fibres having
 a shot content, of shot >45 μm, of less than 51 wt %,   a specific surface area (BET)>0.25 m 2 ·g −1 .   
       and suitable for needling to form a blanket as claimed in  claim 1 . 
     
     
         15 . A self-supporting insulating body other than a needled blanket, formed of fibres as claimed in  claim 14  and having
 a shot content, of shot >45 μm, of less than 51 wt %, 
 a specific surface area (BET)>0.25 m 2 ·g −1 . 
 
     
     
         16 . A self-supporting insulating body as claimed in  claim 15 , in the form of a monolithic refractory fibre module having
 a shot content, of shot >45 μm, of less than 51 wt %,   a specific surface area (BET)>0.25m 2 ·g −1 .   
     
     
         17 . A needled blanket comprising melt-formed inorganic fibres having an overall composition in weight percent
 SiO 2 : 47 to 65%   Al 2 O 3 : 35 to 53%   
       the needled blanket having
 a shot content, of shot >45 μm, of less than 51 wt %, and 
 a specific surface area (BET)>0.25 m 2 ·g −1 , 
 
       wherein SiO 2 +Al 2 O 3 >98%.