US2184308A - Heat exchange apparatus - Google Patents

Description

Dec. 26, 1939. Q H EACH 2,184,308

HEAT EXCHANGE APPARATUS Filed Sept. 18, 1937 2 Slxeets-Sheetl WITN ESSES BY F i MW# M1 ATTORNEYS Dec. 26, 1939. Q H. LEACH 2,184,308

y HEAT EXCHANGE APPARATUS I Filed Sept. 18, 1937 2 Sheets-Sheet 2 BY MGMMW m ATTORNEYS l Patented Dec. 26, 1939 Y UNITED AsTA'rias PATENT OFFICE HEA'Ii.` EXCHANGE APPARATUS y charles n. Leach, Roselle, N. J. Application September 18, 1937, Serial No. 164,458

11 Claims.

` This invention relates to heat exchange apparatus and particularly to heat exchange apparatus used in rening petroleum oil.

It is an object of the invention to provide improved heat exchange apparatus operating at a high rate of efilciency and in which tube erosion and loss of pressure are reduced to a minimum.

My invention relates particularly to heat exchange apparatus in which heat exchange tubes are connected to headers and are encased in a shell, and in which heat is exchanged between fluids. One of the fluids is circulated inside the tubes and the other fluid, usually in the form of vapor, is circulated around the tubes inside the shell. At the point of admission of the vapor into the shell the tubes are usually subjected to :considerable erosion or wear due to the impact of the vaporparticles against the tubes, and also there is considerable localized pressure drop in the vapor at this point. A

It is an object of the invention to overcome the diiculties heretofore encountered in heat exchange apparatus of this character and to .provide improved heat exchange apparatus in which tube erosion and pressure loss is reduced to a minimum.

It is a further object to provide improved heat exchange apparatus as set forth above, of economical construction and in which the heat exchange tubes are readily accessible for inspection and cleaning, and in which guides are provided inside the shell for determining thefposition of the floating heads and so as to permit the ready insertion of the floating heads and heat exchange tubes into the shells and their removal therefrom.

For a fuller understanding of the invention reference should be had to the accompanying drawings, in which:

Figure 1 is a longitudinal sectional view of heat exchange apparatus embodying my invention;

Fig. 2 is an elevation partially in section in the direction' of the arrows on the line 2.2 of Figure 1;

Fig. 3 is a sectional view in the direction of the arrows on the line .3-3 of Figure 1;

'Fig 4 isa sectional viewfin {the direction of the arrows on the line 4-4 of Figure l;

Fig. 5 is an elevation partially in section of the loweriend of heat exchange apparatus embodying my invention and `showing a modified type of shell and baille construction, the tubes and iioating heads being omitted for the sake of clarity;

Fig. 6 isa longitudinal sectional view with the central portion omitted, of the shell of heat exchange apparatus embodying my invention, showing another modified type of baiile construction, the heat exchange tubes and heads being omitted for the sake of clarity; and

Fig. l is a sectional `View in the direction of the arrows on the line 1-1 of Fig. 6.

Heat exchange apparatus embodying my invention preferably comprises a iixed head I0, 10

floating heads I I and I2, tube bundles I3 and I4- connected between the fixed and iioating heads, and a shell I5 encasing the tube bundles andoating heads. In the accompanying drawings I have illustrated a pair of floating heads and tube bundles which give very satisfactory results, but it is to be understood that the number ofV oating heads and tube bundles may be varied. The fixed and floating heads and the tubes form a passage for one of the uids, preferably the 2 cooling fluid, while the shell encases a passage for the other fluid which extends between and around the heat exchange tubes.

'I'he iixed head may be of any desired construction. Thus, as shown, it may comprise an annular member I6 provided with a pair of integral partitions I1 and I8 which provide the iiuid chambers I9, and 2l. A tube sheet 22 is suitably secured to the annular member as by means of bolts 23 passing through the tube 30 sheet and through a flange formed around the lower edge of the annular member. So as to enclose the chambers I9, 20 and 2I a cover memn ber 24 is suitably secured to the upper end of the annular member as by means of` bolts 25 35 passing through the cover member and through a flange formed around the upper surface of the annular member. So as to secure a tight sealving engagement between the annular member and the cover member and the annular member and the tube sheet, an annular rib seated in a groove may be provided at each joint as indicated at 26 and 2'I yand in addition, of course, gaskets maybe employed at these points.

So as to provide an inlet and an outlet forv the cooling uid I provide the annular member IB with a pair of nozzles 29 and 30 which communicate with the chambers I9 and 2I respectively. Tne iiuid may thus be introduced into the chamber I9 through the nozzle 29 and after 50 circulating through the heads, as will be laterexplained, will be withdrawn from the chamber 2| through nozzle 30.

The iioatlng heads II and I2 are preferably oi similar construction, each being formed with a 56 tube sheet 3I having a cover member 32 secured thereto by means of bolts 33, both the tubesheet and cover member being formed with side walls so as to provide an enclosed chamber 34. TheV tubes of the bundles I3 and I4 are expanded into openings formed in the tube sheets of the oating and xed heads so that the inside of the tubes communicate with the chambers formed inthe heads.

The tubes of bundle I3 are connected attheir lower ends with the noa-ting head II lso as to communicate with the chamber formed therein and at their upper ends are connected with xed head I0 so that some-of the tubes-communicate with chamber I9 andthe remaining tubes communicatewith chamber 2 II. Similarly, thetubes ofthe bundle I4 are connected to the oating head I2 at their lower ends, so as to communicate with the chamber therein, and attheir upper ends with iixed head I Il, so that some of the tubes communicate with the chamber 2|, while the remaining tubes communicate with the chamber 20. In this way a continuous and unobstructed fluid passage is provided by means of the xed head, the tubes and the oating heads. Thus the uid may be introduced through the nozzle 29 into the chamber I9, whence it travels through vthe tubes communicating therewith to the oating head II, and from there returns through the remaining tubes of bundle I3 to the chamber20 in the fixed head. 'I'he fluid then travels through the tubes of bundle I4, which communicates with chamber 20, to` the iloating head I2, and then through the remaining tubes of bundle I 4 -into chamber 2| and out through nozzle 30. Another uid passage, encasedby shell I5, is provided around the outside of thetubes so that heat may be exchanged between the uid inside and outside-the tubes.

The structure heretofore described may be theV same in each form of my invention. The shell and baille structure shown in the rst four iigures of the drawings will n ow be described.

The shell I5 comprises a cylindrical portion 36 provided with a flange at its upper end, indicated at 31, which is connected -by means of bolts 23 to the fixed head. The cylindrical portion 36 is preferably spaced a short distance from the outer tubes in the bundles I3 and I4 and extends from the xed head to a short distance above the floating heads, where it' connects with an adapter which may take the form of a tapered collar pornon 3s at the end of which an enlarged beu 39 is formed. The lower end of the enlarged bell 39 is enclosed by means of a dome or cap 40. Each oi.'

the portions of the shell indicated at 36, 38, 39 and 40 may be formed separately and welded together at points 4I, 42 and 43. However, this is merely a matter of construction and two or more of the parts may be formed in one piece'if desired.

So as to provide an inlet and outlet for the vapor which is circulated inside the shell, nozzles 44 land 45- are formed in the bell 39 at opposite sides thereof. The relativejsizes of the tube bundles, iloating heads and shell are preferably such that the nozzles 44 and 45 communicate with the interior of the shell at a point beneath the floating heads II and I2. Due tol the fact that the nozzles 44 and 45 communicate with the enlarged area enclosed within the bell 39 beneath the tube bundles, the entering vapor does not impinge against the tubes, and accordingly, tube erosion at this point. is eliminated. Also, the localized pressure loss usually occurring at this -point is reduced to a minimum due to the enlarged chamber beextended below or to the level of the nozzles and the advantages set forth above will still be obtained but to a lesser degree due to the enlarged chamber provided by the bell.

So as to provide a double-pass vapor passage extending longitudinally of the tubes a longitudinal baille 46 is positioned in the shell between the floating heads. The baille preferably extends from the bottom of the shell to a point adjacent the xed head, being preferably welded along the edges to the dome 40, bell 39, collar 38, and cylindrical section 36. It may be formed in one piece, in which event it must be inserted inside the shell before the dome 40 is welded over the lower end of the bell, or if desired, it may be formed in sections corresponding to the shell section, each section of the baille being welded to its respective section of the shell and abutting end to end when the shell sections are assembled as shown in Figs. 1 and 2. When the shell sections are welded together the sections of the baille may be welded together to form an integral baille as shown in Fig. 1.

So as to provide communication between the two passes formed by the baille 46, the baille is preferably provided adjacent its upper end with apertures 4'I. Thus a complete vapor passage is provided. 'Ihe vapor may be introduced intothe shell through the nozzle 44, whence it will travel upwardly in contact'with the tubes of tube bundle I4, through the apertures 41, downwardlyin contact with the tubes of tube bundle I3 and out through the nozzle 45.

'I'he collar 38 or other adapter should be lso formed as to direct the vapor into vcontact with the tubes, but so as to preventtoo sharp an impact which would result in excessive erosion. Thus the taper of co1lar 36'is relatively gradual. I.have found that a more even distribution of the yapor and a more vemcient and uniform trans.

fer of heat is obtained by spacing the floating heads away from the central baille 46, and to accomplish this I provide a pair of guide ribs 48 at each side of the baille and positioned so as to engage the inner surface of the floating heads II and I2 so as to cause them to be spaced aare welded to the inside of the collar 38 and the l bell 39 for guiding the floating heads.

'I'he guide ribs 48 and-49 are preferably of such a size and shape as to provide a slight clearance between the oating heads and ribs so as to permit the ready insertion of the tubes and oating heads into the shell to the-position shown in Fig.

. 1 and also'their removal therefrom. Due to the guide ribs just described, the bolts 23 may be removed and the tubes and oating heads may be withdrawn from the shell without any danger of interference between the oating heads and the wall of the cylindrical portion 36 of the shell.

' iioating heads to be located in a more central The guide ribs also permit the tube bundles and position when in use thereby providing a space between the baille and the floating heads as wellV as between the shell wall and iioating heads.

As the vapor passes through the passage in the shell in contact with the tubes it isy progressively cooled and a portion thereof condenses and drops into the dome 40 of the shell. Due to differences in temperature, condensates' of different character will form on the two sides `of the baille 46 and separate bleeds or drains are provided on the two sides of the baille. The drains are indicatedat 50 and 5I respectively, the drain 56 being positioned beneath-the tube bundle I4 and having a nozzle 52 connected thereto, and the drain 5I being positioned beneath the tube bundle I3 and having a nozzle 53 connected thereto.

So as to support the heat exchange apparatus in the desired position, as illustrated, with the fixed head'at the top and with the enlarged bell and floating heads depending downwardly, suitable supporting lugs 54 may be formed on the cylindrical portion of the shell as shown most clearly in Fig. 2. Y

In using apparatus of the character just d'escribed a. suitable cooling uid such as crude oil. water or the like, is introduced through nozzle 29 andisrcirculated through the heat exchange tubes, floating heads and chambers formed in the fixed head, and is then withdrawn through nozzle 30.

The hot petroleum vapor which is to be cooled or condensed is introduced through nozzle 44. It will be seen that the vapor from nozzle 44 enters the enlarged space or chamber beneath the floating head I2, thereby eliminating direct impingement of the vapor particles against the heatl exchange tubes, and also 'minimizing pressure drop at this point. The vapor becomes equally distributed throughout the chamber and then passes upwardly through the space provided by the guide ribs on all sides of the iioating head I2, where it is directed inwardly into contact with the tubes .of tube bundle I4. Due to the relatively gradual taper of the collar 38 sharp impact between the vapor .particles and the tubes is prevented. However, because of the progressive restriction of the passage, contact between the vapor particles and tubes is insured. The vapor passes upwardly in contact with the tubes of the bundle I4, thence through the apertures 41 and downwardly in contact with the tubes in bundle I3 into the chamber formed in the bell beneath the tubes and thence outwardly through the nozzle 45. It will be seen that the cooling fluid and the. vapor travel in a general direction of counter-flow.A As the vapor is progressively cooled through its contact with the heat exchange tubes as it travels through the vapor passage, portions thereof are condensed, the heaviest oils condensing rst, adjacent the beginning of the passage,

and the lighter oils condensing later, against the end of the passage. The condensed oils flow downwardly due to gravity and finally are deposited upon the dome 46 and pass outwardly through the drains 50 and 5I, the condensate coming through the drain 50 being of a somewhat heavier character than the condensate coming through the drain 5I.

Referring now to the modified form of some of the sections of the shell, instead of being .welded together, are provided with bolting conshell and baiile shown in Fig. 5, it will be seen that the shell. Thus, the cylindrical .section 36 is illustrated as being provided with a ange 55 at its lower end, and the collar 38 is provided with a flange 56 at its upper end, the two anges being bolted together by means of bolts 51. The collar 38 and'bell 39 are welded together as in the first form of my invention. However, thedomeJIl` is provided with a flange 58 at its upper end, and the bell 39 has a flange 59. at its lower end, the two flanges being secured together by-means of l0 the bolts 66. In this form of my invention the baiie 46 is preferably formed in three separate sections abutting end to end, correspondin'g'to the shell sections. The threesections of the bailles are indicated at 6I, 62 and 63, the section 6I being welded to the inside of the cylindrical portion 36 of the shell, the section 62 being welded to the inside of the collar 38 and bell 39, and the section 63 being welded to the inside ofthe dome 46. When the shell is thus formed in separable sections the supporting lugs 54 are preferably secured to the bell 39 as indicated. In this way the upper and lower sections of the shell may be removed Without the necessity of disconnecting nozzles 44 and 45 from the inlet and outlet pipes.

In the form of my invention shown in Fig 6 the shell 50 is formed similarly to the shell inthe ilrst form of my invention. The baille 4'6 however, is .of somewhat different construction. Thus, the baille is Aformed of a rectangular plate 65 of uniform width from top to bottom, and which extends from adjacent the top of the shell to a short distance from the bottom thereof. The plate 65 is connected as by means of bolts 66 to wing-like projections 61 projecting from the bottom of the shell and from the opposite sides thereof and extending from top to bottom. The winglike projections 61 are welded to the different sections of the shell vand it will be seen that they vary in width so as to compensate for the taper of the collar and the greater width of the bell portion of the shell. In this form of my invention` the plate 65 of the baille maybe conveniently removed from the shell by removing the bolts 66. The forms of my invention shown in Figs. 5, 6 and '7 likewise are provided with guide ribs 48 and 49 similar to those provided in the rst form of myr invention. y

As has previously been stated. the tubes, float#- ing heads and-shell are preferably of such a size that the floating heads are positioned above the nozzles44 and 45 and the most satisfactory results are obtained when the floating heads are thus positioned. However, the floating heads may extend downwardly to a point adjacent the nozzles 44 and 45 and a reduction in erosion and localized pressure drop will also be obtained due extending down to a point adjacent the lower 60 level of the nozzles 44 so as to permit relatively longer tube bundles to be employed in which the floating heads will extend downwardly to this point. However, the guide ribs 48 and 49 in this form of my linvention may be located similarly to the guide ribs of the first form of my invention. 'I'he tubes, floating heads. xed bead and the connections between the fioatingheds and the x'ed head in the forms of my device shown in Figs. 5, 6 and '7, are similar to the arrangement shown in the first form of my invention," and the operation of the apparatus is likewise similar.

It will be appreciated from the accompanying drawings and the foregoing description that I have provided improved 4heat exchange apparatus to I which is specially suited for the refining of petroleum oil, which will operate at a high rate of eiliciency, and in which tube erosion and undesirable loss of pressure are reduced to a minimum It should be understood that modifications may bemade in the illustrated and described embodiments of my invention without departing from the invention as set forth in the accompanying claims.

I claim:

1. Heat exchange apparatus comprising a fixed head, a floating head spaced from the fixed head, heat exchange tubes connected between the fixed and iioating heads so as to form a fluid passage, a shell enclosing the tubes and the floating head, and a baiiie inside the shell extending from the end of the shell adjacent the floating head to adjacent the opposite end so as to form a vapor passage between and around said tubes, said shell having a cylindrical portion spaced a short distance from the heat exchange tubes and extending from the fixed head to adjacent the floating head, and an enlarged bell portion positioned adjacent the floating head and connected by means of a tapered collar to the cylindrical portion, the bell. portion being formed with a dome at the end thereof and with a vapor inlet nozzle at the side thereof and communicating with the inside of the shell on one side of the baille.

2. Heat exchange apparatus comprising a fixed head, a plurality of, floating heads spaced from the fixed head, heat exchange tubes connected between the xed and floating heads so as to form a fluid passage, a shell enclosing the tubes and floating heads, and a baille inside the shell for forming a vapor passage extending between and around the, tubes, the shell having an enlarged portion of greater cross sectional area-adjacent the floating head and having vapor inlet and outlet nozzles formed in the enlarged portion.

3. Heat exchange apparatus comprising a xed head, a plurality of floating heads spaced from the fixed head, heat exchangentubes connected between the xed and oating heads so as to form a fiuid passage, a shell enclosing the tubes and floating heads and releasably secured to the fixed head, a baille secured inside the shell for forming a vapor passage extending between and around the tubes and positioned in a plane between two adjacent floating heads so that the floating heads and tubes may be removed from the shell without interference from theh baille, said shell being'formed with an enlarged bell portion adjacent the floating heads and with vapor inlet and outlet nozzles formed therein'so as to communicate with the interior ofthe shell on opposite sides of the baille, and means for spacing the floating' heads from the baille and for maintaining them in that position while in use.

4. Heat exchange apparatus comprising a xed head, a plurality of floating heads spaced from the fixed head, heat exchange tubes connected between the fixed and floating heads so as to v form a fluid passage, a shell enclosing the tubes and iioating heads and releasably secured to the fixed head, a baille secured inside the shell for forming a vapor passage extending between and around the tubes and positioned in a plane between two adjacent oating heads so that the floating heads and tubes may be removed from the shell without interference from the baille, said shell being formed with an enlarged bell portion adjacent the floating heads and with vapor inlet and outlet nozzles formed therein so as to communicate with the interior of the shell on opposite sides of the baille, and guide means mounted on the insideof the shell adjacent the point of connection between the enlarged bell portion and the remainder of the shell for facilitating the insertion and removal of the floating heads.

5.l Heat exchange apparatus comprising a fixed Ahead, a plurality of floating heads spaced from the xed head, heat exchange tubes Vconnected between the ilxed and oating heads so as to form a fluid passage, a shell enclosing the tubes and floating heads and releasably secured to the fixed head, a baille secured inside the shell for forming a vapor passage extending between and around the tubes and positioned in a plane between two adjacent floating heads so that the floating heads and tubes may be removed from the shell without interference from the baille, said shell being formed with an enlarged bell portion adjacent the floating heads and with vapor inlet and out- 'let nozzles formed thereinso as to communicate with the interior of the shell on opposite sides of the baille, and guide members formed on opposite sides of the baiiie adjacent the enlarged bell portion of the shell for engaging the floating heads and positioning them a spaced distance from the baiiie. f

` 6. Heat exchange apparatus as specified in claim 5 in which additional guide members are formed on the inner surface of the bell portion of the shell to facilitate insertion and removal of the floating heads.

7. Heat exchange apparatus comprising a fixed v head, heat exchange tubes depending downwardly from the fixed head, a floating head secured to thev lower end of the heat exchange tubes so that the fixed and floating heads and heat exchange tubes form a fluid passage, a shell secured to the fixed head and enclosing the heat exchange tubes and oating head, and a baille inside the shell extending from the end of the shell adjacent the'floating head to adjacent the opposite end soA as to form a vapor passage the shell having a. cylindrical portion extending from the fixed head to a short distance above the floating head, and an enlarged bell portion of greater cross sectional area than the cylindricalportion connected to the cylindrical portion by means of a tapered collar and extending downwardly below the floating head, said bell portion being formed with a dome at the lower end thereof and .v having a vapor inlet nozzle formed therein at a point below the floating head.

8. Heat exchange apparatus comprising a fixed head, a plurality of floating heads'positioned beneath the fixed head, heat exchange tubes connected between the fixed and floating heads so as to support the floating heads and so that the fixed and floating heads and the heat exchange tubes form a continuous fluid passage, a shell secured to the fixed head and enclosing the floating heads and heat exchangetubes, said shell having 'a portion of uniform cross sectional area extending from the xed head to adjacent the floating heads and having an enlarged bell portion adjacent the floating heads in which inlet and outlet vapor nozzles are provided, and a baille extending longitudinally of the shell from the bottom thereof to adjacent the xed head so as to provide a vapor passage inside the shell extending between and around the heat exchange tubes. A

9. Heat exchange apparatus as set forth in claim 8, in which the enlarged bell portion extends below the floating heads, and the inlet and outlet nozzles are formed therein at points below the oating heads.

' 10. Heat' exchange apparatus as specified in insertion and removal of the iioating heads.

11. Heat exchangeapparatus comprising a xed head, heat exchange tubes depending downwardly therefrom, a plurality of oating heads secured to the lower ends of the heat exchange tubes so that the iixed and iioating heads and heat exchange tubes form a continuous iiuid passage, a shell removably secured to the flxed head and enclosing the heat exchange tubes and floating heads, said shell having a cylindrical portionjextending from the fixed head to .a 'shortdistance above the floating heads and an enlarediilb'ell Portion of greater cross sectional area than-the@ cylindrical portion extending below the oating heads and connected to the cylindrical portion by means of an adapter, said bell portion being formed with a closure dome at its lower end and with vapor inlet and outlet nozzles at opposite sides at points below the floating heads, a lon- Ngitudinal baille extending from the bottom of the shell to adjacent the iixed head so as to form a vapor passage interiorly of the shell between and around the heat exchange tubes, guide members a formed on the two sides or the longitudinal bame adjacent the bell portion for engaging the oating heads and positioning them a spaced distance from the baille, and additional guide members formed on the inside of the shell to facilitate the. insertion and removal of the floating heads, said dome being formed with separate condensate drains on the two sides ofthe longitudinal baille.

CHARLES H. LEACH. m A

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