Abstract: A method of assembling a catalytic converter comprising the steps of: (1) providing a metal shell exhibiting a predetermined shape that substantially matches the shape of the ceramic substrate; (2) inserting into the metal shell a sufficient amount of a resilient supporting mat material to form a encircling mat layer; (3) compressing the encircling mat layer to an initial gap bulk density, the initial gap bulk density being higher than the final gap bulk density; (4) releasing the compression-on the mat layer and prior to the mat layer reaching its final gap bulk density, inserting at least a portion of the substrate into the encircling mat layered metal shell and then allowing the mat layer to further release until the mat layer is compressed against the ceramic substrate at the final predetermined gap bulk density.

Abstract: A method of assembling a catalytic converter comprising the steps of: (1) providing a metal shell exhibiting a predetermined shape that substantially matches the shape of the ceramic substrate; (2) inserting into the metal shell a sufficient amount of a resilient supporting mat material to form a encircling mat layer; (3) compressing the encircling mat layer to an initial gap bulk density, the initial gap bulk density being higher than the final gap bulk density; (4) releasing the compression on the mat layer and prior to the mat layer reaching its final gap bulk density, inserting at least a portion of the substrate into the encircling mat layered metal shell and then allowing the mat layer to further release until the mat layer is compressed against the ceramic substrate at the final predetermined gap bulk density.

Abstract: A catalytic converter for purifying exhaust gases from an internal combustion engine includes a monolithic ceramic substrate having a peripheral surface encircled by a non-intumescent supporting mat material. A metal shell comprising a wider portion which is adjacent to and encloses the mat material and the substrate. The metal shell further comprises a narrower portion, preferably triangularly shaped, that overlaps and is attached to the outer surface of the wider metal shell portion. The wider and narrower metal shell portions combine to exert a compressive force on the wrapped substrate.