Apparatus for fabrication of solid particulate filters

Abstract

The invention comprises solid particulate filter bodies having so-called 'sloppy' plugging configurations in which clusters of mutually adjoining cell ends are plugged at the two end faces of a honeycomb structure such that the clusters at each end face adjoin or partially overlap one another and at least some of the cells of the structure are closed at both end faces while the remaining cells of the structure are closed at only one end face. Preferably 'sloppy' plugging is accomplished by providing a pair of masks each having a plurality of opening extending therethrough which are sufficiently large to expose clusters of mutually adjoining cell ends and are positioned so as to partially overlap one another when the two masks are aligned opposing one another on opposite end faces of a honeycomb structure. A flowable plugging material charged through the masks plugs the clusters of cell ends at each end face. By simultaneously providing such a pair of masks in alignment opposing one another and against opposing end faces of a honeycomb structure there is no need to achieve exact lateral alignment between the mask openings and the cell ends. Mere positioning of the structure within the area where the mask openings overlap is sufficient. The masks may be fitted to separate feed heads of a cement press or temporarily clamped against the end faces of a honeycomb structure using a suitable frame and the structure charged through the masks by any suitable means. An alternative embodiment employing a single mask for consecutively plugging opposing end faces is also described.