# US 11,306,972 B2 · Shell and tube heat exchangers > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 11,306,972 B2 - Document ID: US11306972B2 - Status: Granted - Kind: B2 - Application number: 16/173,313 - Filed: 2018-10-29 - Published: 2019-05-02 - Granted: 2022-04-19 - Earliest claimed: 2017-11-01 - Assignees: Holtec International - Applicants: Holtec International - Inventors: Krishna P. Singh - Web page: https://patentgrep.com/patent/US11306972B2 ## CPC - F28D 7/1638: {with particular pattern of flow or the heat exchange medium flowing inside the conduits assemblies, e.g. change of flow direction from one conduit assembly to another one (F28D7/1661, F28D7/1676 take precedence)} - F28D 7/005: {the conduits for only one medium being tubes having bent portions or being assembled from bent tubes or being tubes having a toroidal configuration (F28D7/0008, F28D7/02, F28D7/04, F28D7/06, F28D7/14 take precedence)} - F28D 7/0075: {with particular circuits for the same heat exchange medium, e.g. with the same heat exchange medium flowing through sections having different heat exchange capacities or for heating or cooling the same heat exchange medium at different temperatures} - F28D 7/06: the conduits having a single U-bend (F28D7/10 takes precedence){(F28D7/0016 and F28D7/0033 take precedence)} - F28D 7/08: the conduits being otherwise bent, e.g. in a serpentine or zig-zag (F28D7/10 takes precedence){(F28D7/0016 and F28D7/0033 take precedence)} - F28F 9/26: Arrangements for connecting different sections of heat-exchange elements, e.g. of radiators (connecting different sections in water heaters F24H9/14 {, connecting headers with inlet or outlet fittings F28F9/0246}) - F28F 21/081: {Heat exchange elements made from metals or metal alloys} - F28F 21/082: {from steel or ferrous alloys} - F28F 2265/26: for allowing differential expansion between elements - F28F 2275/06: by welding - 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) - F28F: DETAILS OF HEAT-EXCHANGE AND HEAT-TRANSFER APPARATUS, OF GENERAL APPLICATION (water and air traps, air venting F16) ## Abstract A heat exchanger in one aspect includes a longitudinal shell and a transverse shell oriented transversely thereto. A J-shaped tube bundle carrying a tube-side fluid extends through the longitudinal and transverse shells from a first tubesheet in the longitudinal shell to a second tubesheet in the transverse shell. The first and second tubesheets are oriented perpendicular to each other. In a related aspect a dual heat exchanger unit includes a first longitudinal shell, a second longitudinal shell, and a common transverse shell extending transversely between and fluidly coupled to the longitudinal shells. The longitudinal shells may be parallel to each other. The shells are fluidly coupled directly together to form a common shell-side space between pairs of inlet and outlet tubesheets. A pair of J-shaped tube bundles is disposed in the dual heat exchanger unit for heating two tube-side fluids. ## Claims ### Claim 1 A heat exchanger comprising: an elongated longitudinal shell defining a first shell-side space and a longitudinal axis; an elongated transverse shell defining a second shell-side space and a transverse axis; the transverse shell oriented perpendicularly transversely to the longitudinal shell; the transverse shell fluidly coupled to a first end of the longitudinal shell such that the second shell-side space is in fluid communication with the first shell-side space; a tube bundle extending through the first and second shell-side spaces, the tube bundle comprising a plurality of tubes each having a first end coupled to a first tubesheet in the first shell-side space of the first longitudinal shell and a second end coupled to a second tubesheet in the second shell-side space of the transverse shell; wherein the first and second tube-sheets are oriented non-parallel to each other; wherein the tubes each include a straight short section disposed in the transverse shell and fluidly coupled to the second tubesheet, a straight long section disposed in the longitudinal shell and fluidly coupled to the first tubesheet, and a radiused tube bend therebetween; wherein the transverse shell includes a tubeless space defining an auxiliary shell-side flow plenum at a first end portion of the transverse shell opposite a second end portion of the transverse shell attached to the second tubesheet, and a shell-side inlet nozzle on the transverse shell is coupled to the first end portion and arranged to introduce a shell-side fluid directly into the auxiliary flow plenum such that the shell-side fluid expands and undergoes a reduction in velocity before impinging the tubes in the transverse shell; a shell-side fluid inlet head sealably joined to the first end portion of the transverse shell and a tube-side fluid outlet head sealably joined to the second tubesheet in the transverse shell; wherein the longitudinal shell includes a shell-side outlet nozzle oriented perpendicularly to the shell-side inlet nozzle; wherein the shell-side inlet nozzle is configured to direct the shell-side fluid towards the radiused tube bend of each tube; and wherein the shell-side fluid auxiliary flow plenum in the transverse shell has an axial length DV measured along the transverse axis which extends from a terminal end of the shell-side fluid inlet head to a nearest point on the transverse shell where the longitudinal shell is attached to the transverse shell, the axial length DV being at least one quarter of a total axial length of the transverse shell measured along the transverse axis between the terminal end of the shell-side fluid inlet head to a second terminal end of the tube-side fluid outlet head to provide space for expanding the inlet shell-side fluid. ### Claim 2 (depends on 1) The heat exchanger according to claim 1, wherein the longitudinal shell is coupled to the transverse shell inwards of and between opposing ends of the transverse shell. ### Claim 3 (depends on 2) The heat exchanger according to claim 2, wherein the longitudinal shell is oriented perpendicularly to the transverse shell forming a T-shaped heat exchanger. ### Claim 4 (depends on 3) The heat exchanger according to claim 3, wherein the longitudinal shell includes a tube-side inlet nozzle coaxially aligned with the longitudinal axis and a radial shell-side outlet nozzle transversely oriented to the longitudinal axis. ### Claim 5 (depends on 4) The heat exchanger according to claim 4, wherein the shell-side outlet nozzle is located proximate to the first tubesheet. ### Claim 6 (depends on 4) The heat exchanger according to claim 4, wherein the transverse shell includes a tube-side outlet nozzle coaxially aligned with the transverse axis at a first one of the ends of the transverse shell, and the shell-side inlet nozzle coaxially aligned with the transverse axis at a second one of the ends of the transverse shell. ### Claim 7 (depends on 1) The heat exchanger according to claim 1, wherein the tubes are J-shaped collectively giving the tube bundle the same configuration. ### Claim 8 (depends on 1) The heat exchanger according to claim 1, wherein the shell-side fluid flows into the auxiliary flow plenum from the shell-side inlet nozzle in an axial direction parallel to transverse axis of the transverse shell, and the shell-side fluid turns 90 degrees in the auxiliary plenum to enter the longitudinal shell. ### Claim 9 (depends on 1) The heat exchanger according to claim 1, wherein the first tubesheet includes a first end portion having a first diameter, a second end portion having a second diameter, and an annular angled transition portion between the first and second end portions. ### Claim 10 (depends on 1) The heat exchanger according to claim 1, further comprising a planar flow blocker plate oriented parallel to and spaced apart from an inboard face of the second tubesheet, the flow blocker plate sealably welded to the transverse shell forming a dead flow space between the second tubesheet and the flow blocker plate. ### Claim 11 (depends on 1) The heat exchanger according to claim 1, further comprising a tube-side fluid inlet head sealably joined to the first tubesheet at a second end of the longitudinal shell to form a tube-side inlet flow plenum. ### Claim 12 (depends on 11) The heat exchanger according to claim 11, further comprising a radially extending first shell-side outlet nozzle on the longitudinal shell which is oriented perpendicularly to the longitudinal axis of the longitudinal shell, and a radially-extending second shell-side outlet nozzle on the longitudinal shell opposite the first shell-side outlet nozzle, the first and second shell-side outlet nozzles being configured to discharge the shell-side fluid in opposite directions. ### Claim 13 (depends on 12) The heat exchanger according to claim 12, wherein a tube-side fluid flows through the longitudinal shell in a first axial direction, and the tube-side fluid flows through the transverse shell in a second axial direction perpendicular to the first axial direction. ### Claim 14 (depends on 13) The heat exchanger according to claim 13, wherein the tube-side fluid flows in a countercurrent arrangement to a shell-side fluid flowing through the longitudinal and transverse shells. ### Claim 15 (depends on 1) The heat exchanger according to claim 1, wherein the shell-side inlet and outlet nozzles have respective diameters larger than the tubes of the tube bundle. ### Claim 16 (depends on 1) A method for reducing tube-side erosion in the heat exchanger according to claim 1, the method comprising introducing the shell-side fluid through the shell-side inlet nozzle directly into the auxiliary flow plenum, expanding the shell-side fluid, and reducing the velocity of the shell-side fluid before impinging the tubes in the second transverse shell. ### Claim 17 A heat exchanger comprising: an inlet tubesheet and an outlet tubesheet; an elongated longitudinal shell assembly defining a first shell-side space and a longitudinal axis; the longitudinal shell assembly comprising opposing first and second ends, a circumferential sidewall extending between the first and second ends, a tube-side fluid inlet nozzle fluidly coupled to the inlet tubesheet, and a shell-side fluid outlet nozzle fluidly coupled to the circumferential sidewall; an elongated transverse shell assembly fluidly coupled to the first end of the longitudinal shell, the transverse shell assembly defining a second shell-side space and a transverse axis oriented perpendicularly to the longitudinal axis of the longitudinal shell, the second shell-side space being in direct fluid communication with the first shell-side space; the transverse shell assembly comprising opposing first and second ends, a circumferential sidewall extending between the first and second ends, a tube-side fluid outlet nozzle fluidly coupled to the outlet tubesheet, and a shell-side fluid inlet nozzle; a J-shaped tube bundle extending through the first and second shell-side spaces between the inlet and outlet tubesheets, the tube bundle comprising a plurality of tubes each having a first end fluidly coupled to the inlet tubesheet in the first shell-side space of the longitudinal shell and a second end fluidly coupled to the outlet tubesheet in the second shell-side space of the transverse shell; a tube-side fluid flowing through the tube bundle and a shell-side fluid flowing through the longitudinal and transverse shell assemblies; wherein the first and second tube-sheets are oriented non-parallel to each other; wherein the tubes each include a straight short section disposed in the transverse shell and fluidly coupled to the second tubesheet, a straight long section disposed in the longitudinal shell and fluidly coupled to the first tubesheet, and a radiused tube bend therebetween; wherein the transverse shell includes a tubeless space defining an auxiliary shell-side flow plenum at a first end portion of the transverse shell opposite a second end portion of the transverse shell attached to the second tubesheet, and a shell-side inlet nozzle on the transverse shell is coupled to the first end portion and arranged to introduce a shell-side fluid directly into the auxiliary flow plenum such that the shell-side fluid expands and undergoes a reduction in velocity before impinging the tubes in the transverse shell; a shell-side fluid inlet head sealably joined to the first end portion of the transverse shell and a tube-side fluid outlet head sealably joined to the second tubesheet in the transverse shell; wherein the longitudinal shell includes a shell-side outlet nozzle oriented perpendicularly to the shell-side inlet nozzle; wherein the shell-side inlet nozzle is configured to direct the shell-side fluid towards the radiused tube bend of each tube; and wherein the shell-side fluid auxiliary flow plenum in the transverse shell has an axial length DV measured along the transverse axis which extends from a terminal end of the shell-side fluid inlet head to a nearest point on the transverse shell where the longitudinal shell is attached to the transverse shell, the axial length DV being at least one quarter of a total axial length of the transverse shell measured along the transverse axis between the terminal end of the shell-side fluid inlet head to a second terminal end of the tube-side fluid outlet head to provide space for expanding the inlet shell-side fluid. ### Claim 18 (depends on 17) The heat exchanger according to claim 17, wherein the tube-side fluid flows through the longitudinal shell assembly in a first axial direction, and the tube-side fluid flows through the transverse shell assembly in a second axial direction perpendicular to the first axial direction. ### Claim 19 (depends on 18) The heat exchanger according to claim 18, wherein the tube-side fluid flows in a countercurrent arrangement to the shell-side fluid flowing through the longitudinal and transverse shell assemblies. ### Claim 20 (depends on 17) The heat exchanger according to claim 17, wherein the shell-side inlet and outlet nozzles have respective diameters larger than the tubes of the tube bundle. ### Claim 21 (depends on 17) A method for reducing tube-side erosion in the heat exchanger according to claim 17, the method comprising introducing the shell-side fluid through the shell-side inlet nozzle directly into the auxiliary flow plenum, expanding the shell-side fluid, and reducing the velocity of the shell-side fluid before impinging the tubes in the second transverse shell.