Multiple layer mat and exhaust gas treatment device

摘要

A hybrid mounting mat for mounting a catalyst support structure within a housing in an exhaust gas treatment device. The exhaust gas treatment device includes an outer housing, a fragile catalyst support structure, and a mounting mat disposed in the gap between the housing and the fragile catalyst support structure. Additionally disclosed are methods of making the hybrid mounting mat and for making an exhaust gas treatment device incorporating the mounting mat.

主权项

1. An exhaust gas treatment device comprising: a housing; a fragile structure resiliently mounted within the housing; and a mounting mat disposed between said housing and said fragile structure, said mat comprising: a first layer consisting essentially of biosoluble inorganic fibers having a first mean diameter and a second layer adjacent said first layer consisting essentially of substantially non-respirable sol-gel derived inorganic fibers comprising at least about 60% by weight alumina and having a second mean diameter that is greater than said first mean diameter, wherein said first layer is positioned adjacent said housing and said second layer is positioned adjacent said fragile structure.