Interlocking plate heat exchanger
A method for making a heat exchanger includes machining a plate of material having a starting thickness and at least one alignment feature. The machining includes machining down the starting thickness to produce a heat exchanger plate having at least one flow passage segment and at least two ribs arranged extending along each side of the at least one flow segment. The at least one alignment feature is removed to provide a trimmed heat exchanger plate and to stack the trimmed heat exchanger plate with a further heat exchanger plate. The at least two ribs are interlocked with ribs of the further heat exchanger plate and the at least one flow segment is aligned with a flow segment of the further heat exchanger plate. The at least two ribs of the trimmed heat exchanger plate and the ribs of the further heat exchanger plate are joined together.
1 . A method for making a heat exchanger, the method comprising:
machining a plate of material having a starting thickness and at least one alignment feature, the machining comprising machining down the starting thickness to produce a heat exchanger plate having at least one flow passage segment, and at least two ribs arranged extending along each side of the at least one flow segment;
removing the at least one alignment feature to provide a trimmed heat exchanger plate;
stacking the trimmed heat exchanger plate with a further heat exchanger plate with the at least two ribs interlocked with ribs of the further heat exchanger plate, and the at least one flow segment aligned with a flow segment of the further heat exchanger plate; and
joining the at least two ribs of the trimmed heat exchanger plate and the ribs of the further heat exchanger plate together, wherein the machining step produces the heat exchanger plate having the at least one flow passage segment and at least two ribs, and excess material extending in at least one dimension beyond the at least one flow passage segment and the at least two ribs to define the at least one alignment feature, the at least one dimension lying in a plane of the heat exchanger plate, and wherein the step of removing the at least one alignment feature comprises removing the excess material, wherein the machining step comprises machining the at least two ribs to have interlocking structure, wherein the interlocking structure is selected from the group consisting of a convex upward facing surface, a concave upward facing surface, or a combination of a convex upward facing surface and a concave upward facing surface, and further wherein the further heat exchanger plate has ribs that match the at least two ribs such that a convex surface is paired with a concave surface of the at least two ribs, and a concave surface is paired with a convex surface of the at least two ribs.
2 . The method of claim 1 , wherein the joining step comprises a diffusion bonding step.
3 . The method of claim 2 , further comprising applying braze to at least one of the at least two ribs of the trimmed heat exchanger plate and the ribs of the further heat exchanger plate.
4 . The method of claim 1 , wherein the machining comprises wire-EDM machining.
5 . The method of claim 1 , wherein the machining defines a plurality of machined flow passage segments extending along and defining a flow direction of the heat exchanger plate, wherein the at least two ribs comprise a plurality of ribs defined one on each side of each of the plurality of machined flow passage segments.
6 . The method of claim 1 , further comprising machining turbulator structures into a surface of the at least one flow passage segment.
7 . The method of claim 6 , wherein the step of further machining turbulator structures comprises plunge-EDM machining of the turbulator structures.
8 . The method of claim 1 , further comprising machining each side of the plate of material to produce a heat exchanger plate having the at least one flow passage segment and at least two ribs on each side of the heat exchanger plate.
9 . The method of claim 1 , wherein the at least one alignment feature comprises a hole passing through the excess material.
10 . The method of claim 1 , wherein the machining defines the heat exchanger plate having a thickness defined between opposed surfaces of the plate of between 0.005 and 0.020 inches.
11 . The method of claim 1 , wherein the machining defines the heat exchanger having the at least two ribs having a rib thickness of between 0.005 and 0.020 inches.
12 . The method of claim 1 , wherein the machining comprises machining both sides of a plurality of plates to produce a plurality of heat exchanger plates having the at least one flow passage segment and the at least two ribs on a first side, and having a second at least one flow passage segment and at least two ribs on a second side.
13 . The method of claim 12 , wherein the first at least one flow passage segment has different dimensions as compared to the second at least one flow passage segment.
14 . The method of claim 13 , wherein the stacking step comprises stacking the plurality of heat exchanger plates with the first side of one heat exchanger plate facing the first side of an adjacent heat exchanger plate, and with the second side of the one heat exchanger plate facing the second side of another adjacent heat exchanger plate.
15 . The method of claim 14 , wherein the at least one flow passage segment on the first side is perpendicular to the at least one flow passage on the second side.