US 2362985 A
Description (OCR text may contain errors)
Nov. 21, 1944. J. w. BROWN, JR
HEAT EXCHANGER Filed Dec; 24, 1941 3 Sheets-Sheet l aamv w. 320w, we.
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NOV; 21, 194-4.
J. w. BROWN. JR
HEAT EXCHANGER Filed Dec.. 24, 1941.;
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Nov. 21, 1944.-
J w. BROWN, JR
HEAT EXCHANGER Filed Dec. 24, 1941 5 Sheets-Sheet 5 Q INVENTOR. r/OHN w. 520w, =72. BY 5 flTTO/QNEVJ disconnected.
Patented Nov. 21, 1944 UNITED STATES PATENT orricr.
HEAT EXGHANGER I I John W. Brown, Jr., Lakewood, Ohio, assignor to poration of Ohio Brown Fintube Company, Elyria, Ohio, a cor- Application December 24, 1941, Serial No. 424,241
This invention relates to heat exchangers and more particularly -to heat exchangers particularly adapted to take advantage of the heat transferring capacity of finned tubes such as those described -in my Patents Nos. 2,261,136 and 2,261,137, issued November 4, 1941, although other types of heat exchange conductors may be incorporated therein.
heat exchanger embodying my invention; and
Figs. 10, 11 and 12 are transverse sections as indicated by the lines ll0, ll- H and l2 -.l2, respectively, of Fig. 9.
Referring to Figs. 1 to 5, a heat exchanger made according to a. preferred form of my invention A general object of my invention is to provide,
an eflicient heat exchanger which is compact and which can be economically manufactured. Another object is to provide a-heatexchanger embodying a finned tube and arranged to utilize the high heat transfer efliciency of the tube. Another object of my invention is to provide a heat exchanger which-may be readily cleaned and in which the entire cleaning operation can be carried out from one end of the exchanger. Another flow principle within and outside of a single tube. A further object is to provide such a heat ex-' changer which can be adapted to various uses and purposes, and which may be designed to embody various mass-flow characteristics depending upon the service for which the exchanger is intended.
Further objects and advantages of my invention will become apparent from the followingdescription of preferred forms thereof, reference being made to theaccompanying drawings where in Fig. 1 is a longitudinal section through a heat exchanger made according to my invention; Fig. 2 is a transverse section taken along'the line 22 of Fig. 1; Fig. 3 is a transverse section taken along the line 3-3 of Fig. 1; Fig. 4. is a fragmentary longitudinal section taken on a plane at" right angles to the planeof Fig. 1 as indicated by the line l-Jof Fig. 1; Fig. 5 is a fragmentary section as indicated by the line 5-5 of Fig.2; Fig. 6 is a longitudinal section through another form of heat exchanger embodying my invention; Fig. 7 is a transverse section taken along the'line of Fig. 6; Fig. 8 is atransverse section taken along the line 8-8 of Fig. 6; Fig. 9 is a longitudinal section through a third form of may comprise a header l0, shown here as being a header for a single unit, but which can be constructed to accommodate a number of heat exchanger units The header may be a forging or casting, and is provided with inlet and outlet openings l I and I2, respectively, in which the conduits l3 and I4, terminating in conventional flanged couplings, are suitably secured, for example, by welding'as shown. The inlet and outlet passageways join to former central chamber l5 communicating-with the interior of the tube It .which is preferably welded as at l1 into the counter-bored opening l8 in the header; The tube is preferably provided with a plurality of channel section fins I9, preferably of the type more particularly described in my aforesaid patents, to assist in transfer of heat from the commodity within the tube to the commodity on the exterior of the tube. The construction of the fins will be described in greater'detail below.
To cause a proper flow of the fluid within the finned tube from the inlet H to the outlet I2, an
inner tube 20 is disposed within the finned tube IS, the tube 20 being provided with a pair of oppositely disposed fins or baflles 2|, engaging the internal surfac of the finned tube lliand thereby dividing'the annular space between the interior of the finned tube l6 and the inner tube 20 into two substantially equal arcuate passageways indicated at 22 and '23. The inner tube stops short of the end of the'finned tube, leaving a space as at 24, and the ends of both tubes opposite the header are closed, for example, by plates 25 and 26 welded in position. At the opposite end the tube 20 extends beyond the end of the finned tube l6 and into the header, preferably being welded G into place 'within the opening 21 in the boss 28- of the header. The tube 20 and the fins 2| thus function to divide-the chamber l5 in half and to separate the inlet and outlet openings. so'that fluid flowing into the exchanger through the con-r duit I3 is caused to flow outwardly away from the header. through the passageway 22, then around the end of the tube 20 through the space 24, back toward the header through the passageway 23 and out through the discharge conduit M. The tube" is employed to reduce the cross-sectional area of the passageways within theflnned tube IS, the tube diameter being selected to pro- "the-desired annular space to give the proper mass-flow characteristics for the commodities being circulated through the exchanger. As will be described below, the tube is not always necessary or desirable, a flat tongue or baiile being preferred for some purposes.
In order to control the flow of the other commodity or fluid passing through the heat exchanger, shell tube indicated generally at 29 is provided. The internal diameter, of the shell tube is preferably just enough largerv than the external diameter of the fins I! to permit the tubes to be assembled-together readily. The assembly thus embodies a. number of parallel, longitudinally extending passageways between the shell tube and the finned tube as shown particularly in -Fig. 2. At the end adjacent the header the shell baifle flns assist in centering the tubes with respect to each other.
The construction of the exchanger is such that the channels between the shell tube and finned tube may be made-accessibl for cleaning either by disconnecting the two sections of the flnned tube at the flanges 33 and 31 and removing the section 35, using the push bolts 40 to break any adhesion, if necessary, or by disconnecting the header ID from the flange III of the shell tube and pulling out the finned tube from the inside of the shell tube. If the flanges 38 and 31 are disconnected the cleaning operation can be effected without disturbing any one of the fluid connections, and if the exchangers are arranged in a bank'the whole bank of exchangers will be accessible for cleaning from the end opposite the fluid connections. If the connection is broken, between the header and the flange 30,
disassembling the exchanger, the shell tube may be made up of two sections 34 and 35 provided with flanges 36 and 31 which may be secured together by bolts 38, with a gasket 39 interposed to provide a leakproof joint. In order to facilitate breaking the connection between the sections, push bolts 40 as shown in Figs. 2 and 5 may be employed. The end of the section 35 away from the header is closed by any suitable closure member such as the cap ll welded thereto.
It will 'be noted that the flns l9 terminate adjacent the ends of the inlet and outlet conduits 32 and 33. To insure the proper flow of fluid through the passageways formed by the flns between the flnned tube and the shell tube, the finned tube is provided with a pair of oppositely disposed baflle fins l2 and 43 shown particularly in Figs. 2 and 4 and which extend to the header.
These baflie flns function to divide the annular space between the shell tube and the flnned tube adjacent the inlet conduit and outlet conduits 32 and 33 into two zones 44 and 45, respectively. Fluid entering the shell tube through the conduit then it will be necessary to disconnect the fluid connections to the conduits l3 and I 4 or to the conduits 32 and 33, but not to all four of the conduits, and the cleaning operation then can be carried out from either end of the exchanger.
depending upon which of the conduits are disconnected. Ordinarily if the exchanger is designed for such an installation the shell tube will .be made in one piece, eliminating the flanges 36 and 31 and the connection at this point. If the exchanger is designed for the installation first described above, the flange 21 to which the shell tube is secured may be formed integrally with the header if desired.
To facilitate the handling of the shell tube incident to cleaning operations, I may provide means for supporting the shell tube in alignment with the finned tube so that 'it' may be moved into and out of position with a minimum amount of eflort and without any danger of damaging the flns of the flnned tube. For example, section 35 of the shell tube may be provided with U-shaped brackets 53 and SI suitably secured to the exterior of the tube as by welding, and
to the axis of the flnned tubeand is supported 32 is prevented from flowing directly around the finned tube to the outlet conduit 33 by the batfle fins l2 and 43 and is distributed from the chamber 44 into the passageways formed by the -fln members IS on the lower half of the flnned tube as shown in the drawings. The fluid flows out along thaflns to the end space 43 and around the flow of the other commodity.
The baflle flns 42 and 43, as well as-the ballle flns 2| on the inner tube 23 are preferably formed in such a position that there will be clearance between the flange 31 and the I-beam and that the axes of the finned 'tube and the shell tube will substantially coincide. By this arrangement,
withthe flanges of the channels bent as at 41, I
and with the outer edges bent or rolled over as at 43 toprovide a resilient structure. With this construction, the baiile fins can be proportioned to resiliently engage the inner surfaces of the respective tubes and thus make sealing connections with the tubes adequate to prevent any substantial fshort circuiting" of the fluidsin their flow through the exchanger. Further, the
one man can readily disassemble a large heat exchanger, handling a heavy shell tube section that may be several feet long. Supporting tracks or trolleys are illustrated in the drawings only with respect to this form or my invention. However, it is to be understood that supporting tracks may be used with the otherforms of my invention, and those skilled in the art will appreciate that the supports may be modified to suitthe and according to the method described and claimed in my copending application Serial No. 388,835, flled April 16, 1941, now Patent 2,298,250 issued Oct. 6, 1942, to provide adequate paths for the flow of heat from the fins to the tube. In Flgs..6 to 8 I have illustrated another form of heat exchanger made according to my invenfinned tube.
' ployed within the finned tube a tongue such as tion. In this type of exchanger the header 60 is formed by a plate. having openings BI and 62 therein to receive the inlet and outlet conduits 63 and 64, respectively. These conduits are preferably in the form of 90 bends as shown and are provided with suitable means for making fluid connections such as the coupling flanges ila lust'rated. The conduits are preferably welded into the openings H and .62 and the connection between the conduits and th interior of the finned tube 65 is made by bolting the plate 60 to the flange 66 which is welded onto 'the end of the finned tube. In this modification instead of employing an inner tube as in the previous modification, the fluid is caused to flow out to the end of the finned tube and back again by abaflle or tongue 61 which abuts the plate 60 as at 68 and stops short of the closed end 69 of the finned tube, leaving a passageway I around the end of the tongue. Fluid entering the inlet conduit 63 flows out around the end ofthe tongue 61 and back through the lower half of the finned tube to the discharge conduit 64. This construction is particularly useful where it is not necessary to have a high velocity of flow on the inside of the For example, when steam is emshown in this modification is frequently satisfactory, it being unnecessary to employ an inner tube such as shown in the previous modification.
The heat exchanger shown'in Figs. 6 to 8 is also modified in the construction of the shell tube, which is produced from two semi-circular pieces II and 12 having inturned flanges" and .14, the
pieces being. welded together as shown at I and 16. It will be noted that the inturned flange provides a groove at the juncture of the two pieces, this facilitating arc welding'of the parts. The shell tube is secured to the header assemblyby a flange I1 welded to the end of the shell tube and bolted to the flange 66 which is, as noted above, welded to-the finned tube and bolted to the header plate 60, suitable gaskets being employed where required. Push bolts (not shown) may be employed to assist in breaking these connections if desired. The inlet I8.and the outlet I9 of the noted, the construction is substantially the same as that shown and described with reference to Figs. 1 to 5.
In Figs. 9 to 12 a further modificationis illustrated, in which the inlet and outlet connections 1 respect to Figs. 6 to 8 including a bailie or tongue I 3 94 which abuts the plate 85 at one end and is f spaced from the closure plate 95 at the other end to provid a passageway. The finned tube is provided with a plurality of fins 96 and oppositely disposed baflle fins 91 and 98, the baflie fins being of resilient construction similar to fins '42 and 43 and engaging the inner surface of the shell tube 99. p
In order to support the finned tube within the shell tube the finned tube is provided with a .flange I00 welded thereto near the threaded-end fitting 90. The end of the finned tube is extended through an opening in the plate IM and the flange is drawn up tightly against the gasket I02, which abuts the plate, by a large nut I03 which is threaded on the end fitting 90'. The shell tube is also supported from the plate IOI, being provided with a flange I 04 welded to. the end thereof and bolted to the flange MI.
The shell tube has inletand outlet openings I06 and I0! similar to those previously described but instead of having a welded closure at its end,
shell tube are formed as described above with I respect to the inlet 32 and outlet 33.
In this modification the fins 80 on the tube 65 are shown as having their outer edges spaced from the inner surfaces of the shell-tube. -Th1s arrangement is desirable for some services, particularly where viscous or sticky liquids are circulated through the heat exchangers. By having the fins spaced from the inner surface of the shell tube, there is less likelihood of the finned tube becoming stuck within the shell tube. To prevent fluid from flowing directly around the finned tube from the inlet I8 to the outlet 19, the baffle fins 8| and 82 are employed. These are spring fins of the same general type as described above and engage the inturned flanges I3 and 14 on the interior of the shell tube.' This arrangement provides an adequate seal, and further, the fins-'with their engagement with the flanges I3 and 14 and with the inner surface of necting the connections to the conduits I8 and- 19 and removing the bolts that connect the.
flange I! to the flange 66. Except for thechanges shell tube.
exchanger can be disassembled for cleaning it is provided with a closure plate I08 which is bolted to the flange I09 welded to the end of the With this type of construction the either by breaking the connections to the conduits I06 and I 01 and loosening the bolts securing the flanges IOI and I04 together, which makes it possible to remove the shell tube from the finned tube, or the plate 85 may be disconnected from the end fitting 90, the nut I03 unscrewed from the end fitting and the end plate I08 removed, thus permitting the finned tube to be removed from the exchanger from theend opposite the fluid connections.
From the foregoing description of preferred forms of my invention it will be seen that I have provided compact heat exchangers which can be economically manufactured. By reason of the counter-flow principle preferably embodied in my exchangers and the arrangement of the tubes and battles, very eflicient heat exchange characteristics are obtained, thus providing exchang-. ers which can take advantage of the high heat as in such instances it is very difficult to make leak-tight connections and it is desirable to maintain' the connections without disturbing them,
The interior arrangement of even though the exchangers should require cleanmg.
The heat exchangers disclosed herein prefer ably embody finned tubing made according to my application aforesaid; however, it is to be understood that different types of heat exchanger conductors can be employed if desired. Also, features described with respect to any one form 'of 'the interior of the inner of said tubes, an inlet conduit and an outlet conduit connected to the annular space between said tubes, all of said conduits being disposed adjacent one end of the heat exchanger, means closing the end of said annular space adjacent said end of the heat exchanger and both of said tubes being closed at the opposite end of said heat exchanger, baflle means within the inner of said tubes dividing it into two longitudinally extending passageways communicating with each other only adjacent the closed end thereof, the inlet conduit for the interior of said inner tube being connected to one of said passageways and the outlet conduit therefor being connected to the other, and bailie means within said annular space dividing said space into two longitudinally extending passageways.com- ,municating with each other only adjacent the closed ends of said tubes, the inlet conduit for said annular space being connected to one of said passageways therein and the outlet conduit for said annular space being connected to the.othersaid passageways therein, both said baflle means lying in the same general longitudinal plane of the heat exchanger.
2. A heat exchange comprising two concentric -tubes with an annular space therebetween; an
inlet conduit and an outlet conduit connected to the interior of the inner of said tubes, an inlet conduit and an outlet conduit connected to the annular space between said tubes, all of said conduits being disposed adjacent one end of the heat outlet conduit therefor being connected to the other, said inner tube being provided with a plurality of longitudinally extending external fins, andbaflle means within said annular space dividing said space into two longitudinally extending passageways communicating with each other eral longitudinal plane of the heat exchanger.
3. A heat exchanger comprising two concentric tubes with an annular space therebetween, an inlet conduit and an outlet conduit connected to the interior of the inner of said tubes, an inlet conduit and an outlet conduit connected to the annular space between said tubes, all of said conduits being disposed adjacent one end of the heat exchanger, said tubes being detachably secured together adjacent said conduits and both of said tubes being closed at the opposite end of said heat exchanger, bafile means within the inner of said tubes dividing it into two longitudinally extending passageways communicating with each other only adjacent the closed end thereof, the inlet conduit for the interior of said inner tube being connected to one of said passageways and the outlet conduit thereforjbeing connected to the other, and baflie meanscomprising two oppositely disposed longitudinally; extending fln memberssecured to said inner tube and engaging said outer tube dividing said annular space into two longitudinally extending passageways communicating with each other only adjacent the closed ends of said tubes, the inlet conduit for said annular space being connected to one of said passageways therein and the outlet conduit for said annular space being connected to the other of said passageways therein, both said baflie means lying in the same general longitudinal plane of the heat K exchanger.
JOHN w. BROWN, JR;