Patent ID: 8667681

Claim:
A method of achieving an installed mat density (IMD) in a catalytic unit having at least one layer of support mat sandwiched between a catalyst carrier and a shell, the mat having a weight m mat and a width B mat , the catalyst carrier having a cross-sectional area A substrate , the method comprising the steps of: calculating a desired annular cross-sectional area A gap of a gap between the catalyst carrier and the shell based on the following calculation: A gap = m mat I ⁢ ⁢ M ⁢ ⁢ D * B mat calculating a target cross-sectional area A case for an inside diameter of the shell based on the following calculation: A case =A substrate +A gap calibrating the shell by altering the inside diameter of the shell to achieve the calculated A case after the catalyst carrier and support mat are assembled into the shell.