Most catalytic converter designs today utilize monolith type catalyst supports. Many of these designs use more than one monolith because of different catalyst loadings, or constraints on the manufacture or coating of long monoliths. Usually a space exists between the monoliths. Traditional thinking has been that spacing was necessary for enhanced emissions, reduced flow restriction, or concerns about the physical integrity of the monoliths.
This paper presents the concept of eliminating the space, and butting the monoliths together as a viable converter assembly technique. Major benefits include simplified assembly, reduced number of components and cost, and improved durability, with no major effects on emissions or flow restriction.