# US 2014/0151001 A1 · Heat exchanger with variable thickness coating > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 2014/0151001 A1 - Document ID: US20140151001A1 - Status: Published application - Kind: A1 - Application number: 13/857,245 - Filed: 2013-04-05 - Published: 2014-06-05 - Earliest claimed: 2012-12-05 - Assignees: Hamilton Sundstrand Corporation - Applicants: Hamilton Sundstrand Corporation - Inventors: Marc E. Gage; Jeffrey A. Scarcella; Kurt L. Stephens; Matthew Patterson - Web page: https://patentgrep.com/patent/US20140151001A1 ## CPC - F28F 19/02: by using coatings, e.g. vitreous or enamel coatings - F28D 9/00: Heat-exchange apparatus having stationary plate-like or laminated conduit assemblies for both heat-exchange media, the media being in contact with different sides of a conduit wall {(F28F3/083, F28F3/086 take precedence)} - F28D 2021/0021: {for aircrafts or cosmonautics} - F28F: DETAILS OF HEAT-EXCHANGE AND HEAT-TRANSFER APPARATUS, OF GENERAL APPLICATION (water and air traps, air venting F16) - F28D: HEAT-EXCHANGE APPARATUS, NOT PROVIDED FOR IN ANOTHER SUBCLASS, IN WHICH THE HEAT-EXCHANGE MEDIA DO NOT COME INTO DIRECT CONTACT (fluid heaters having heat generating means and heat transferring means F24H; furnaces F27; details of heat-exchange apparatus of general) ## Abstract A heat exchanger includes a heat exchanger wall that bounds a passage. A coating lines the heat exchanger wall. The coating has a thickness that varies according to location on the heat exchanger wall. ## Claims ### Claim 1 A heat exchanger comprising: a heat exchanger wall bounding a passage; and a coating lining the heat exchanger wall, the coating having a thickness that varies according to location on the heat exchanger wall. ### Claim 2 (depends on 1) The heat exchanger as recited in claim 1, wherein the coating is organic. ### Claim 3 (depends on 1) The heat exchanger as recited in claim 1, wherein the coating is an epoxy-based coating. ### Claim 4 (depends on 1) The heat exchanger as recited in claim 1, wherein the heat exchanger wall has an edge and a location spaced from the edge, and the coating is thicker at the edge than at the location spaced from the edge. ### Claim 5 (depends on 4) The heat exchanger as recited in claim 4, wherein the edge is a leading edge with respect to the passage being arranged to receive a flow of a fluid. ### Claim 6 (depends on 4) The heat exchanger as recited in claim 4, wherein the edge is a trailing edge with respect to the passage being arranged to receive a flow of a fluid. ### Claim 7 (depends on 1) The heat exchanger as recited in claim 1, wherein the heat exchanger wall has an edge and the coating has a maximum thickness at the edge. ### Claim 8 (depends on 1) The heat exchanger as recited in claim 1, wherein the coating has a gradual transition between a maximum thickness location and a minimum thickness location. ### Claim 9 (depends on 1) The heat exchanger as recited in claim 1, wherein the coating has a maximum thickness of T1 and a minimum thickness of T2 such that a ratio of T1/T2 (T1 divided by T2) is equal to or greater than 2. ### Claim 10 (depends on 9) The heat exchanger as recited in claim 9, wherein the ratio is from 3 to 7. ### Claim 11 (depends on 9) The heat exchanger as recited in claim 9, wherein the ratio is 10 or greater. ### Claim 12 (depends on 9) The heat exchanger as recited in claim 9, wherein the maximum thickness T1 is greater than or equal to 25.4 micrometers. ### Claim 13 (depends on 12) The heat exchanger as recited in claim 12, wherein the maximum thickness T1 is greater than or equal to 2.54 micrometers. ### Claim 14 (depends on 1) The heat exchanger as recited in claim 1, wherein the thickness of the coating varies according to a location on the heat exchanger wall that is more susceptible to corrosion than at least one other location. ### Claim 15 A heat exchanger comprising: an inlet face arranged to receive ram air; an exit face opposed from the inlet face; a plurality of heat exchanger walls extending between the inlet face and the exit face, the plurality of heat exchanger walls defining a plurality of passages that open at respective leading edges at the inlet face and at respective trailing edges at the exit face; and a coating lining the plurality of heat exchanger walls, the coating having a thickness that varies according to location on the plurality of heat exchanger walls. ### Claim 16 (depends on 15) The heat exchanger as recited in claim 15, wherein the coating has a maximum thickness at the leading edges. ### Claim 17 (depends on 15) The heat exchanger as recited in claim 15, wherein the plurality of heat exchanger walls are metallic and the coating is organic. ### Claim 18 (depends on 15) The heat exchanger as recited in claim 15, wherein the coating has a maximum thickness of T1 and a minimum thickness of T2 such that a ratio of T1/T2 (T1 divided by T2) is equal to or greater than 2. ### Claim 19 (depends on 15) The heat exchanger as recited in claim 15, wherein the thickness of the coating varies according to a location on the plurality of heat exchanger walls that is more susceptible to corrosion than at least one other location on the plurality of heat exchanger walls. ### Claim 20 A method of protecting a heat exchanger from corrosion, the method comprising: providing a heat exchanger wall that bounds a passage; identifying at least one location on the heat exchanger wall that is more susceptible to corrosion than at least one other location on the heat exchanger wall; and providing a coating on the heat exchanger wall in a thickness that varies according to the identified locations such that the coating has a first thickness T1 at the location on the heat exchanger wall that is more susceptible to corrosion and a second, different thickness T2 at the least one other location on the heat exchanger wall, where T1 is greater than T2.