Muffler shell filling process and muffler filled with fibrous material

摘要

A process is provided for filling a muffler shell with fibrous material. It comprises the step of providing a muffler shell comprising one or more muffler shell outer parts which define an internal cavity and an internal structure adapted to extend at least part way through the shell internal cavity and having one or more openings adapted to communicate with the shell internal cavity. The process further comprises the step of providing a bag filled with fibrous material. The bag has a first side with one or more first perforations defining a first side total open area and a second side with either no perforations or one or more second perforations defining a second side total open area. The first open area is greater than the second open area. The process also comprises the steps of positioning the fibrous material-filled bag adjacent the internal structure such that the first side is nearest to the internal structure, and drawing a partial vacuum through the internal structure, the partial vacuum drawing the fibrous-filled bag inwardly towards the internal structure.