Surface coated filter and method
A filter element is provided. The filter element includes a filter media pack including an outer surface. The outer surface extending between a first flow face and a second flow face. The filter element also includes a polymeric coating applied to the outer surface of the filter media pack, wherein the polymeric coating is not a molded structure. In embodiments, the polymeric coating covers at least 25% of a span between the first flow face and the second flow face and has an average thickness of between 0.005 and 0.100 in. In other embodiments, the polymeric coating has a surface roughness of at least 50 μin to provide an outer gripping surface. A method and system for applying the polymeric coating to the filter element are also provided.
1 . A filter element, comprising:
a filter media pack including an outer surface, the outer surface extending between a first flow face and a second flow face;
a polymeric coating applied to the outer surface of the filter media pack, wherein the polymeric coating is not a molded structure; and
wherein the polymeric coating comprises a material other than polyurethane, wherein the material is provided with:
(a) a penetration portion penetrating into the outer surface; and
(b) an outer layer portion integrally connected to the penetration portion, the outer layer portion extending outwardly from the outer surface of the filter media pack.
2 . A filter element, comprising:
a filter media pack including an outer surface, the outer surface extending between a first flow face and a second flow face;
a polymeric coating applied to the outer surface of the filter media pack, wherein the polymeric coating is not a molded structure; and
wherein the polymeric coating comprises a polyurea, wherein the polyurea is provided with:
(a) a penetration portion penetrating into the outer surface; and
(b) an outer layer portion integrally connected to the penetration portion, the outer layer portion extending outwardly from the outer surface of the filter media pack.
3 . The filter element of claim 1 , wherein the polymeric coating is selected from the group consisting of acrylic, epoxy, silicone, polyurea, polyaspartic, aliphatic polyurea, polystyrene, polyethylene, ethylene-vinyl acetate, polyethylene-vinyl acetate, ethylene propylene diene monomer, polyurea/polyurethane hybrid, and combinations thereof and wherein the polymeric coating optionally includes fiberglass, roughening agents, or other fillers.
4 . The filter element of claim 1 , wherein the polymeric coating comprises a spray coating layer.
5 . The filter element of claim 1 , wherein the polymeric coating has a Shore A Durometer hardness of between about 60 and about 95.
6 . The filter element of claim 1 , wherein the filter media filter pack is a wound pack having an annular shape, a leading edge of the wound pack being in a radial center of a pack and a trailing edge of the wound pack being along the outer surface forming a step, the polymeric coating filling in and sealing the step and preventing unfiltered fluid flow leakage from the first flow face to the second flow face, without any additional materials applied along the step between the polymeric coating and the filter media filter pack.
7 . The filter element of claim 1 , wherein the filter media pack is constructed of a filter media and comprises a fluted filter media filter pack comprising a face sheet and a fluted sheet in a wound or stacked configuration for form a plurality of layers such that unfiltered fluid must pass through the face sheet or the fluted sheet to pass from the first flow face to the second flow face.
8 . The filter element of claim 1 , wherein the polymeric coating has a surface roughness of at least 1,000 μin, and a Shore A Durometer hardness of between about 60 and about 95.
9 . The filter element of claim 1 , wherein the polymeric coating has a surface roughness of at between 5,000 and 9,000 μin.
10 . The filter element of claim 1 , wherein the polymeric coating is impermeable to air and moisture such that air and moisture cannot penetrate through the polymeric coating.
11 . The filter element of claim 1 , wherein the polymeric coating is applied to at least 25% of the outer surface extending between the first flow face and the second flow face.
12 . The filter element of claim 1 , wherein the polymeric coating is applied in at least two coats, with the outer surface of the filter media pack being coated a first time with the polymeric coating and then is coated at least a second time with the polymeric coating.
13 . The filter element of claim 2 , wherein the polymeric coating comprises a spray coating layer.
14 . The filter element of claim 2 , wherein the polymeric coating has a Shore A Durometer hardness of between about 60 and about 95.
15 . The filter element of claim 2 , wherein the filter media filter pack is a wound pack having an annular shape, a leading edge of the wound pack being in a radial center of a pack and a trailing edge of the wound pack being along the outer surface forming a step, the polymeric coating filling in and sealing the step and preventing unfiltered fluid flow leakage from the first flow face to the second flow face, without any additional materials applied along the step between the polymeric coating and the filter media filter pack.
16 . The filter element of claim 2 , wherein the filter media pack is constructed of a filter media and comprises a fluted filter media filter pack comprising a face sheet and a fluted sheet in a wound or stacked configuration for form a plurality of layers such that unfiltered fluid must pass through the face sheet or the fluted sheet to pass from the first flow face to the second flow face.
17 . The filter element of claim 2 , wherein the polymeric coating has a surface roughness of at least 1,000 μin, and wherein the polymeric coating has a Shore A Durometer hardness of between about 60 and about 95.
18 . The filter element of claim 2 , wherein the polymeric coating has a surface roughness of at between 5,000 and 9,000 μin.
19 . The filter element as in claim 1 , wherein the outer layer portion has an average thickness of between 0.005 and 0.100 inches.
20 . The filter element as in claim 1 , wherein the outer layer portion has an average thickness between 0.020 and 0.050 inches.
21 . The filter element of claim 20 , wherein the penetration portion penetrates the filter media pack to a depth of at least 9,000 μin to extend around and interlock with fibers of filter media of the filter media pack.
22 . The filter element of claim 1 , further comprising a housing gasket formed separately from the polymeric coating, the housing gasket being of a different material than the polymeric coating.
23 . The filter element as in claim 2 , wherein the outer layer portion has an average thickness of between 0.005 and 0.100 inches.
24 . The filter element as in claim 2 , wherein the outer layer portion has an average thickness between 0.020 and 0.050 inches.
25 . The filter element of claim 24 , wherein the penetration portion penetrates the filter media pack to a depth of at least 9,000 μin to extend around and interlock with fibers of filter media of the filter media pack.
26 . The filter element of claim 2 , further comprising a housing gasket formed separately from the polymeric coating, the housing gasket being of a different material than the polymeric coating.