Catalyst carrier holding mat and process for production of catalytic converter

Abstract

A catalyst carrier holding mat is rolled around a catalyst carrier so as not to wrinkle when rolled, and the catalyst carrier is thereby uniformly compressed. Furthermore, method of forming a catalytic converter in this manner is also provided.

What is claimed is:  
     
         1 . A catalyst carrier holding mat rolled around an outer surface of a catalyst carrier accommodated in a cylindrical casing along a circumferential rolling direction, the mat holding the catalyst carrier in the casing by being compressed between the catalyst carrier and the casing, the mat comprising: 
 a convex part formed on one side of the rolling direction of the mat and projecting in the rolling direction,    a concave part formed on the other side of the mat to fit with the convex part,    the convex part and the concave part extending parallel to the rolling direction in condition of fitting together to enable control of the rolling diameter, and    corner parts included in the convex part and the concave part, the corner part formed into an R shape with a radius of not less than 5 mm or a linear-chamfered shape.    
     
     
         2 . A producing method for a catalytic converter comprising the following steps: 
 inserting a cylindrical catalyst carrier rolled by a mat into a cylindrical casing,    compressing the mat by reducing the diameter of the casing so as to hold the catalyst carrier in the casing, wherein    calculating an inner diameter of the casing after reducing diameter thereof based on a surface density of the mat and an outer diameter of the catalyst carrier before the reducing diameter and a predetermined filled density of the mat after reducing diameter of these mat and catalyst carrier, and    reducing the casing until an inner diameter of the casing reaches the calculated inner diameter of the casing.