Coreless non-metallic filter element

Abstract

A coreless filter element for a filter housing includes cylindrical filter media having longitudinally-extending pleats extending from one end cap on the filter media to another end cap on the filter media. The filter media is preferably a multi-layered structure with an outer support mesh layer attached to an inner prefiltration layer by an intermediate adhesive web layer. An inner wrap of a porous fibrous filter media is provided within the central cylindrical cavity of the pleated filter media. The wrap has a cylindrical form with an outer surface which is joined to the inner pleat peaks of the media such as with one or more beads of adhesive, or with a continuous adhesive layer applied to the outer surface of the support wrap. The filter element with inner support wrap can be easily located over a metal support core integral with the filter housing, and provides structural integrity for the pleats of the filter media. According to another embodiment, a series of circumferential bands formed from porous or imperforate material can be provided within the central cylindrical cavity and adhesively joined to the inner pleat peaks of the filter media. In either embodiment, the inner support wrap or bands provide structural integrity for the pleats, provides a filter element which is easily manufactured, and which allows the filter element to be easily located over the support core in the filter housing, and removed therefrom when the filter element becomes spent. The coreless filter element is also preferably formed from components which can be easily incinerated or disposed of in a landfill.