Patent ID: 8753414

Claim:
A filter cassette assembly for mounting onto a partition of a filtration unit, the partition having an opening therethrough and defining a plane separating a clean air side from a dirty air side of the filtration unit, the filter cassette assembly comprising: a. a filter cassette having a frame and filter media pleat pack, an upstream end and a downstream end, and a mounting frame connected to the filter media pleat pack adjacent to the upstream end of the filter cassette, the mounting frame having a mounting face adapted for mounting the filter cassette, and b. a mounting flange extension, permanently or removably attached to the partition, and disposable to extend between the partition of the filtration unit and the mounting frame of the filter cassette, the mounting flange extension having a first mounting surface for mounting attachment to a mounting face of the partition and a second mounting surface for mounting attachment of the mounting frame of the filter cassette thereto, wherein said mounting flange extension has a depth sufficient so that, when said first mounting surface of said mounting flange extension is mounted to said mounting face of the partition and said mounting face of said mounting frame is mounted to the second mounting surface of said mounting flange extension, said filter media pack extends through the mounting flange extension and the opening of the partition so that a portion of the filter media pleat pack is positioned on the clean side of the filtration unit with regard to the partition plane and another portion of the filter media pleat pack is positioned on the dirty side of the filtration unit with regard to the partition plane, and wherein said mounting flange extension provides a stand off distance from the mounting frame of the filter cassette to the dirty side of the partition, said stand off distance being at least 10% of the overall length of the filter cassette.