US1757136A - Heat exchanger - Google Patents

Description

R. J. PABODIE May 6, 1930.

HEAT EXCHANGER 5 Sheets-Sheet Filed Sept. 4, 1926 BY MAL@ 71W [2M] n //s ATTORNEYSl HEAT EXCHANGER Filed Sept. 4, 1926 5 Sheets-Sheet 2 7 /3 f) um /1/3 ATTORNEYS.

May 5, 1930- R. .1. PABoDlE I 1,757,136

HEAT EXCHANGER Filed Sept. 4, 192i: 5 Sheets-Sheet 3 /5 ATTORNEYS R. J. PABODIE HEAT EXGHANGERA May 6, 1930. Y

FiledSept. 4, 1926 5 Sheets-Sheet 4 @ww/fw ls ATTORNEYS R. J. PABODIE HEAT EXCHANGER May 6, 1930.

Filed Sept. 4, 1926 5 Sheets-Shea?l 5 M @WMM/ag /5 ATTORNEYS Patented May 6, 1930 UNITED STATES PATENT OFFICE ROBERT JEWETT PABODIE, 0F MAYWOOD, ILLINOIS, ASSIGNOR TO THE GRISCOM'.- RUSSELL COMPANY; OF NEW YORK, N. Y., A. CORPORATION OF DELAWARE amr Exc'HANGEn Application led September 4, 1926. Serial No. 183,525.

This invention relates to heatexchanging in general and resides in certain lmprovements in multiple-section cooling apparatus.

In oil refinery Work and in other Work in which a fluid other than a non-corrosive liquid such as Water is the medium to be cooled or heated by surface heat exchangmg, due provision must be made for the corrosive and clogging eects of the medium. It is also 1mperative that the utmost possible eiiciency be obtained in transferring the heat contentof this medium, as,-for example, in gasoline producer plant operation,-the operativeness of the plant may depend entirely upon the completeness with which the heat content of the medium is interchanged in certain stages of the flow of the medium. The mechanical construction of the heat exchanger isan important item and applies particularly to the attaining ofthe maximum thermal efficiency in the particular form of construction employed, per unit of length, and also the flexibility of the assembly as a whole as regards varying its constituents to meet changing operating conditions. The floor or wall space occupied by the multiple-section assembly is, of course, in some cases controlling, but probably the most important consideration of all is the way in which the parts are designed and put together and the degree of mechanical efficiency in operation of theassembly, such as the fluid-tightness of the joints, ease of cleaning, and control of expansion strains and the like.

It is contemplated by the present invention to provide a multiple-section" heat exchanger which shall be of general usefulness and adapted for employment for Vheat eX- changing between all kinds of fluids, whether they be corrosive or non-corrosive in action, or sluggish, or rapid in flow.

It is another primary object of the invention to provide a heat exchanger in which an increased rate and eclency of heat exchange shall result from directed flow of the media A therein.

It is also an object of the present invention to provide a heat exchanging apparatus or cooling machine, in which there shall be little or no tendency to cause deposition of clogging matter Within its enclosures, walls, or sides, and further, shall be susceptible of easy and rapid cleaning in case it should be used in work in Which such deposition is unavoidable, as in handling fluids carrying an unusual amount of sediment.

Another object of the present invention is to furnish an apparatus of this class which shall have sections capable of manipulation and easyadjustment in such a manner as to prolong the life of the heat exchanger beyond that expected of ordinary heat exchangers.

A particular object of the present invention is to reduce the number of joints required in a sectional heat exchanger, and additionally, to make and maintain these joints luidtight, not only on the outside enclosures of the heat exchanger, but on the inside enclosures as well.

n A further particular object of the present Invention is to provide a heat exchanger, of this type which shall be capable of trapping off any liquids which may be fractionated therein, in order to increase the efliciency of the heat exchanger.

A still further particular object of the present invention is to accommodate all expansion strains which may tend to occur in the heat exchanger, and in such a manner that no gaping or opening at the joints can occur.

The invention will be further described in connection with the acompanying drawings forming a part of the specification and which disclose only those of the various successful embodiments of the present inventiomwhich have been chosen to be herein disclosed. It is to be understood that these drawings and the subsequent description thereof are given only for the purpose of specifically disclostional view of an extension ange designed vdouble-pipe iiow elements, shown in Figure 1, with portions ofl the element broken' away for convenience;

Figure 3 is a view along line 3-3 of Figure 2, sighting in the direction of the arrows;

Figure 4 is a vertical, longitudinal, sectional view of another embodiment of the present invention; v Figure 5` is a sectional view of one of the elements of Fig. 4;

Figure 6 is a view along line 6-6 of-Figure 5 Figure `7 is a'sectional view of one of the joints of Figure 4; t

Figure 8 is a vertical, longltudinal, secto connect two flow-sections in series;

Figure/9 is a detail View of two doublepipe flow sections connected in series by meansfof the extension flange shown in Figure 8;

Figure 10 is a fragmentary front elevation, partly in section, ofstill another embodiment of the present invention; y a

Figure 11 is a sectional view along line 11-11 of Figure 10, sighting in the direction of the arrows;

Figure 12 is a fragmentary front elevation, partly in section, of still another advantageous embodiment of the present invention;

Figure 13 is a sectional view along line 13-13 of Figure 12, sighting in the irection of the arrows;

Figure 14 is a fragmentary front elevation, partly in section, of a further embodiment of the present invention, and

Figure 15 is asectional view along line 15-15 of Figure 14, sighting in the direcl tion of the arrows.

`Referring now to the drawings more in detail'b numerals, an advantageous embodiment o the invention is shown in Fi res 1 and 2 as comprising straight, concentric ipes 1, and concentric return-bends 6, to whic are connected two of the sections 1 to form a U-iiow section. The sections are preferably in number,cast between these bend elements at each end ofthereturn-bend, the connecting projections :or bolting ears 7 being cast on the return-bend in the positions shown in Figure 3. The true positionsof these lugs is not shown in Figure 2, the positions shown in Figure 3 being more accurate. The center ones of the ears 7 may be cast together, as shown 1n Figure 3in order to prevent the return-bend from springing out of the proper' shape, and the two inside or center ears 7 of the connected How-'sections 1 may likewise be c'ast lntegral but it is preferred to leave :them unconnected and in stub form, in order 'to permit the accomplishment of the object of prolonging the life of the flow.' sections, by adjustmgand manipulating them in a manner to be described later. v

Near each end of each element l, are cast a plurality of connectors or lugs 4, which may be similar to the lugs 5 in the return bends, and-here shown as four in numberin which connect solidly an inner concentric pipe 3 to an outer concentric pipe 2. These connecting bridging or spacing lugs 4 are cast narrow `in the direction of iiow of the medium by which they are traversed, in order to offer as little head resistance as possible to the fluid-flow. These lugs 4 make integral the two concentric pipes 2 and 3 so that they can all be cast in one mold. These bridging lugs are further contemplated by the present invention as being so arranged in the interior of the pipe-section as to straddle the vertical center-line of the section, as shown, so as to form an unobstructed, non-clogging flow path therein.

On the outside of the exchanger, at each end of an element 1, thereA are formed a plurality of projections, bolting-lugs or ears 7,

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here shown as four in number, and provided with suitable openings or bolt holes for re- .ceiving bolts or other 'suitable fastening means. These projections or ears 7 are formed on the outside of the outermost of the concentric pipes, always directly opposite the connect-ing or spacing lugs 4and on the same perpendicular axis therewith, `in order to concentrate the pull of the connecting bolts to this point and thereby to make and maintain an absolutely Huid-tight joint.

These projections or ears 7 are spaced 90 apart on the periphery of the outer walls 2. The reason for this arrangement of parts is that, when'for example, a gaseous fluid is being passed though the exchanger, the condensate will invariably sett-le to the bottom of each section and run along in a comparatively narrow and restrictedpath. Even cast-iron walls such as those of the exchanger 'of the present invention would eventually it will be possible to not only merely lift out the entire assembly and turn it upside down, thus exposing a new, smooth surface to the vaction of the condensate, but also to disas semble the various pipe elements 1 and return bends 6 and turn the sections through a vertical angle of 90, to thus bring into contact with the eroding liquid, a new, unimpaired surface. Inasmuch as this rotation cany be performed four times in 360, it is evident that the life; of each section iS quadrupled by this construction and arrangement of parts.

The spacing projections or lugs 4 connecting together the inner and outer pipes 2 and 3 straddle the vertical centerline of the crosssectional area of the passage-ways 23, as will be evident from Figure 3, thereby leaving unrestricted the path naturally followed by condensate which may form within the exchanger. This feature efliciently prevents any clogging of the outer enclosure or gasside.

At the top and at the bottom of the assembly, there are provided inlet and outlet connections or fittings 26. These fittings are connected or bolted to the element 1 1n a manner similar to that in which the elef ments are connected together, as will be seen from Figure 1. According to one 4,method of employing the heat exchanger offf'the present invention, the medium tobe'f cooled, or the hot medium, of any composition or in any fluid state, enters thr/,ou'gh the connection or inlet 13, passing irri/directed flow through the outer annular space or gas-side 23 of the exchanger, and/discharging through the outlet 16; andthe cooling medium, or waste fluid, is admitted through the connection or inlet 15, passing in directed counter-flow through the water-side22 of the exchanger and discharging through the outlet 14.

At the returnvbend end of each bottom member of the assembled` members, and optionallyralso at the bend-end of higher sections, may` be provided enlargements or liquid pockets 9, for the purpose of trapping liquids condensed at fractional temperatures where the fluid or gas to be condensed flows through in the outer annular space 23. These fractionated liquids may then be drawn off through openings or plug holes 21. 'However, the heat exchanger of the present invention is capable of vbeing used for work in which these pockets 9 may be superfluous or even deleterious, and thereforeit is to be 1,9', w ich are composed of suitable material. Itis a partof the present invention to make the outer gaskets 19 slightly thicker than the inner gaskets 19 int'der to compensate for the pulll of the bolts connecting the joints together, which pull will always tend to be slightly heavier on the outside than on the inside. These features thus maintain absolutely fluid-tight joints throughout'the apparatus. The gaskets are centered b the centering rings 11 and locked by gaskets rolding-rings 12, as best seen in Figure 2.

If desired, adjustability forlong life may be sacrificed to high rate of flow, and the joints 25 may have their faces 10a pitched to a predetermined degree, as shown best in the alternative forms in Fig. 5 or Fig. 2, in order that each flow section 1 may have a downward slope to facilitate the flow of the fiuids therein. It is to be understood, however, that the invention does not contemplate the necessity of,l making every embodiment thercofin this manner, as this Structure is 'not mandatory and the heat exchanger operates satisfactorily Without being so made.

In Figure 3 are shown the faces of the joints 25, looking in the direction of a bend 6, and it is seen that the connecting lugs 4 and 5 straddle the vertical center line of the section and thus leave a free and unrestricted passage foi` the flow of the condensate and hence there is no tendency whatsoever for the flow in the exchanger to become clogged.

Each of the return-bends 6 may be provided on its lower surface with a hollow chair 9 which will thus serve both as a spacing member and as a trap for fractional condensates formingin the outer side 23. On the upper surface of each return-bend 6 may be provided a solid chair 9', in order to complete the spacing means between the U-bends of the assembled sections. L

By making the lugs 7, on the inside of the turn of the return-bends 6, integral across the bend, as shown in Fig. 1, and better in 7d of Fig. 3, the entire assembly can be lifted up as a unit and turned upside down, for the purpose hereinbefore described.

In Figures 8 and 9 is shown an extension flange 17. Due to mechanical diiiiculties, the length in which the flow-sections 1 can conveniently be made is limited. There arise, however, in practical operation, condie tions where it is desirable, in order to attain to' the correct ratio of llength of travelof the fluids to ideal heat transfer for the articular conditions and fluids in question, to ave long assemblies of the straight path pipes, but only one or two sections high. By meansv of this element of the invention, that'is,the ex-A tension flange 17, this desideratum can beaccom lished. This extension flange is a doubleaced flange with both sides or faces simi- .lar in construction .to the return-bend shown in Figures 2 and 3. The inner pipe-section 3 is made integral with the outer pipe 2', by lugs4,l and suitable connections or bolts can be placed in the bolt holes 18 provided in the ears 7. The locking rings 12 and centering rings l1 function as shown in Figure 9 to properly hold inplace the two pipe sections to be connected in series. It is evident that by the use of this flange as many sections as are deemed necessary can be placed together in series, or in combination with the return` bends 6, according to the desired ratio of heat transfer to length of travel of the fluids.

In Figures 4, 5, 6 and 7 is shown an'embodi- .ment ofthe present invention differing from the embodiment shown in vFigures 1 to 3 inclusive in that it com rises elements l formed integral with the el ows or return-bends of Figures 1 to 3 inclusive. The advantages of this modification are that it combines a lowered cost of manufacture with an equal me-v chanical and thermal efliciency.

In Figures 10 and 11 is shown a modification of the embodiment shown in Figures 1 "o 3 inclusive, which differs from that embodiment in several important structural fea# tures, notably in the advantageous location and shape of the spacing lugs 5, wherebythe number 'of lugs re uired is decreased; the different design of t e bolting lugs 7; and the elimination of the chairs 9. This modifica tion can, as well as the modification shown in Figure 5, also be providedwith pockets or tra s 9. A

- n; Figures 12 and 13 is shown another modification of the embodiment shown in Fi res 1 to 3 which differs from those e'mbo iments in comprising several `structural variations therefrom, notably in that, though there are separate return bends and separate inlet-outlet pieces, successive straight pipe elements 1 are connected vertically by a web, such as 24. Also, the inner kpipe in the 'straight elements, is separate` from the outer and rests on it by means of lugs 4, by which lugs it can be brought into four different positions with four different sides of the pipe occupying thebottom position.

In Figures 14 and 15 is shown still another modification of the embodiment shown in Figures 1 to 7, vwhich differs therefrom in that the lugs 4 are modifiedinto combined bolting and spacing lugs 4'; in that the inlet and outlet connections are simplified, and in that many other structural simplifications are embodiedwhich are evident from the'figures'. The inner and outer concentric pipes a not cast integral, .but instead the smaller innerv pipe 3 rests on the inner surface of the lar er pipe 2 by'meanspof the lu 4', which aso` serve to )om the varlous sections of the pipe`3..

tortuous ow, surface contact, heat exchangers.

Inpractice,the heat exchanger of the pres` n ent invention occupies a` floor .or wall space which is small in proportion to the volume of the fluids which can be -operated uponl per unit o f time. The ever present liability of leaky and heat losing joints is decreased by eliminating most of the joints. Thesame improved structure which assures the roperlength of travel of the fiuids for satis actory heat transfer for the liuids in question also permits of easy access to the cleaning pur-` poses when working with' materials holding easily precipitated solids in a sol condition therein; andv incidentally, reduces clog g of the improved flow-paths therein. s a matter of a purely economic nature, the reversible flow-sections constitute the heat exchanger an apparatus which has substantially four times the durability of that of the usual type of tortuous flow heat exchangers.

. I claim:

1 A heat exchanger, comprising a plurallty of flow-sections, said sections being formed into an upper'arm and a lowerl arm connected bya return bend in such a manner that thev flow through each section at its outlet end is substantiall opposite in direction to that at its inlet en each of said sections having an inner conduit and an outer enclosure therefor, said inner conduit and said outer enclosure being integrally connected near each end of each section to form an antherebetween; and having on the outside of one end of said sections on the same perpendicular axes as said connections, means for connecting said sections to return bends.

3. A heat exchanger comprising a pluralitl of integrally-concentric pipes and return bends, connected together at their ends on their interiors by spacing lugs, said bends having at said ends, inner centering lips and outer locking lips, said lips forming recesses to receive outer and inner ring gaskets; and around the periphery of the outermost of the concentric pipes and bends, at the ends thereof and on the same perpendicular axes as the said lugs, a plurality of equidistant projections so placed as to connect together said pipes and bends, and to concentrate t-he connecting-pull along these axes.

4. A heat exchanger of the class described, comprising a flow-section having integrally lconcentric pipes, a return-bend having integrally concentric pipes, a double-pipe inlet connection, a double-pipe outlet connection and a chamber formed in the Wall of the outermost of the concentric pipes, on the lower side of one of said bends.

l5. A heat exchanger, comprising a plurality of elements, each of said elements including two concentric pipes, said elem'ents being arranged one above the other in a vertical plane and being connected in series by return bends tov form zigzag passages, each of said elements being separated from a d supported above the next lower element by a hollow chamber on the lower side of the upper of the adjacent returns bends, and a solid chair on the upper side of the lower of the adjacent return bends.

6. In a. heat exchanger of the class described, a plurality of heat-transferring elements, comprising a plurality of concentric pipes integrally connected at each end in the interior thereof, by projections therebetween; and means on the outside of said sections and on the same radial lines as said connections,

for connecting said elements to return bends.

7 In a concentric pipe element, return bend heat-exchanger, means whereby a channel worn in the. bottoms of the pipes may be replaced by a fresh, unchanneled surface, comprising a plurality of bolting lugs on the outer periphery of the ends of the separate pipe elements and spaced equidistantly therearound, and an equal number of bolting lugs equally spaced around the ends of the arms org the return bends against which said pipes a nt.

8. In a concentric pipe element, return bend heat-exchanger, joints between said pipe-elements and said bends, and a structure for preventing said joints from opening up under operating stresses, comprising a plurallty of bridging lugs connecting said concentrlc pipes to each other at each end. thereof and connecting the concentric pipes 1n the return bends at each end of said return bends, and an equal number of bolting lugs forrholding said pipe sections and bends together, said bolting lugs being disposed equidistantly on the ends of the outer periphery of the outer concentric pipe on the line-prolongation of the axesof said bridging lugs.

9. In a concentric pipe-element heat exchanger, an inner conduit, .an outer conduit encasing it, and bridging lugs at each end of each element for connecting said conduits integrally, said bridging lugs being disposed on both sides of the Vertical centerline of cach of lsaid pipe-elements so as to straddle said center-line and thereby form an unobstructed l,central flow-passageway in the pipe element. l

.heat-exchanger of the type described, ha warg a plurality of pipe elements connected at their ends to form flow-channels by return bends, each element comprising a smaller pipe v and a larger pipe, the smaller pipe being connected concentrically with the larger ipe by integral lugs, other lugs extending out eyondthe outer side of said larger pipe and in line with the first-mentioned lugs for connecting the elements to the bends, said outer lugs being so spaced on the exterior of the outer'pipe as to transmit the connecting strains to the inner pipe, whereby no unbalanced forces come on said connection.

11. A heat exchanger of the type described, having a plurality of double-pipe elements connected at their ends by double pipe return f bends, each element including a smaller pipe and a larger pipe, the smaller pipe being formed concentrically integralwith the larger pipe by lugs therebetween, said lugs being located in pairs to one side of the top and bottom ends of the vertical center-line of the element and other lugs on the outside of the larger pipe and in line with the first-mentioned lugs forming means for connecting said'sections to said bends, whereby no longitudinal unbalanced forces exist at said connection.

12. A heat exchanger of the type described, having a plurality of double pipe elements connected at their ends by double pipe return bends, eachelement including a smaller pipe and a larger pipe, the smaller pipe being formed concentrically integral with the larger pipe by lugs therebetween, said lugs being located in pairs to one side of the top and bottom ends of rthe vertical center-line of the section! and other lugs on the outside of the larger pipe and in line with the rst mentioned lugs forming means for connecting said sections to said bends, said return bends comprising pipes held in concentric relation by lugs in their interiors at each end and other lugs on their exteriors to. connect the bends with the elements.

concentric pipe-elements and double concentric return bends connecting said i elements, a-joint betweenthe bends and) tlee elements Acomprising lips on the' ends of the inner pipe of the return bend, tongues on the inner ipe of .the pipe elements, lugs connectiing v t e concentric pipes of the pipe elements at the ends of the pi elements, lugs on the out'sideof the pipe e ements forming connectingv ears, and complementary similarly 10 laced lugs on the ends of the return bends, or connectigg the plpe elements tothereturn bends at sal Joint. A

In testimon whereof I aix myv si ature.

ROBE T PAB Dm.

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