US2916264A

US2916264A - Heat exchanger

Info

Publication number: US2916264A
Application number: US565500A
Authority: US
Inventors: Hubert F Rhodes
Original assignee: Phillips Petroleum Co
Current assignee: Phillips Petroleum Co
Priority date: 1956-02-14
Filing date: 1956-02-14
Publication date: 1959-12-08
Anticipated expiration: 1976-12-08

Description

H. F. RHODES HEAT EXCHANGER Dec. 8, 1959 2 Sheets-Sheet 1 Filed Feb. 14. 1956 INVENTOR. H. F. RHODES BY M4 1' M AT ORNEY H. F. RHODES Dec. 8, 1959 HEAT EXCHANGER 2 Sheets-Sheet 2 INVENTOR. H. F. RHODES BY M4 M A ORNE Filed Feb. 14. 1956 tween the tube bundle and said shell.

United States Patent '0 2,916,264 I HEAT EXCHANGER Hubert F. Rhodes, Bartlesville, kla., assignor to Phillips Petroleum Company, a corporation of Delaware Application February 14, 1956, Serial No. 565,500 6 Claims. (Cl. 257-439 This invention relates to construction of shell and tube bundle type heat exchanges. In one of its aspects, the invention relates to the disposition within the shell of such an exchanger of a fluid-conducting box or flume so constructed, arranged, and disposed that it receives fluid entering the shell side of'the heat exchanger and conducts the said fluid to the tube side of a tube sheet and there discharges said fluid on to the ends of the tubes at said tube sheet in a direction substantially at right angles to the axis of said tubes into an annular space be- In another of its aspects, the invention provides a bafiie arrangement in which baflies extend alternately from the shell across the tubes but terminating before reaching the other side of the shell, and from the other side of the shell across said tubes and again terminating before reaching the first-mentioned side of said shell, thus providing a continuous zigzag channel for passage of fluid over a substantial distance of the tube bundle while always maintaining said fiuid when in contact with the tubes in said tube bundle flowing in a direction substantially at right angles to the axis of said tubes.

An object of the invention is the provision of an improved construction and design for a heat exchanger or" the shell and tube bundle type. Another object of the invention is the provision of means for conducting fluid flowing into a heat exchanger from a peripheral or annular portion of the exchanger into right-angle contact with the tube ends at the tube sheet. Another object of the invention is to provide such a contact in a heat exchanger in which at least one end of the tube bundle is of the floating-header equipped type, the construction of which will not permit the simple use of a shell on the tube bundle positioned opposite an inlet which, but for the construction of the device, could be placed at the tube end of the bundle.

'A further object of the invention is to providefor flow of fluid over a substantial distance along the tubes of a tube bundle in a heat exchanger, the said fluid at all times while in contact with the tubes flowing substantially at right angles to said tubes.

Other aspects, objects, as well as the several advantages of the present invention, are apparent from this disclosure, the drawings, and the appended claims.

In the description of the drawings, which follows, it

should be noted that the preferred arrangement of the invention constitutes a distributor or box or flume disposed within an annular portion formed between the shell and the tube bundle of a heat exchanger, the said flume being so constructed and arranged as to receive fluid flow- 'ing into the shell and to conduct the same to a tube sheet end of the bundle and to there discharge the same in said annulus along the inner periphery of the shell and at right angle to the axis of the tubes in said bundle. It will also be noted that a similar arrangement can be provided at the discharge end of the shell side of the exchanger. Further, in one embodiment of the invention,

2,916,264 Patented Dec. 8, 1959 longitudinal axis of the device of'Figure 1 at line 22 and shows generally the arrangement of the device at the place at which the fluid surrounding tubes, shown inFigure 1, enters'the device. Thus, Figures 1 and 2 are to be viewed together. It will be apparent that the crosssection illustrated in Figure 2 is substantially the same as would be obtained had the line 2 2 been taken at the right-hand end of Figure 1 except that the view shown in Figure 2 would then have to' be rotated through and there would have to be shown additional details of construction of the device which are here not directly pertinent to the invention described. Figure 3 is a plan view of a horizontal cross-section of the internals of the device taken at a level which is above plate 18. Figures 4, 5 and 6 are to be viewed together. Figure 4 illustrates an alternative construction of at least the in-flow section for fluid to surround the tubes and Figures 5 and 6 are taken respectively along the lines of 55 and 6-6 of Figure 4, Figure 4 being a plan view of a horizontal cross-section of the internals of the device taken at a level which is above plate 53. Compare inlet pipe 54 of Figure 5 at the top of Figure 5 with the dashed circle 54 of Figure 4. Figure 7 is an isometric view, partly broken away, of the shell fluid 'inlet end of the heat exchanger, showing the inlet device of my invention.

Referring now to Figure l and to Figure 2, the latter being a view of an inlet arrangement of Figure 1, 10 denotes the outer shell of the device. Fluid desired to be passed into contact with the external surfaces of the tubes within the device is passed downwardly by way of conduit 22 onto the top of plate 18. Plate 18 is in effect a humped bottom of a distributor device or box which is defined in part by the top of baflle 16, which forms the right-hand end of the box and by

plates

29 and 30, see Figure 2. Still'viewing- Figure 2, it will be noted that plate 29 does not reach tube sheet- 24, which would be between the viewer and Figure 2. Also, the spacing of plate 29 from plate 30 is such that there is provided a continuous channel leading from inlet pipe 22 down to the bottom of the box, onto plate 18, and thence to the end of plate '29 around the end of plate 29 at which place fluid passing through the channel Will spill over end 19 of plate 18, see Figure 3. In other words, viewing Figure 3, liquid, or fluid, which enters by way of pipe 22 will go down through the pipe into the shell and will flow bounded by the shell 10, plates 29 and 3t) and tube sheet 24 until it reaches the end of plate 18 whereupon it will spill downward over the tube ends. If desired, plate 18 of Figure 1 can be modified by providing therein a few holes 70 through which some liquid or fluid can flow directly down the ends of those tubes which are immediately adjacent the underside of plate 18. In the event end 1g is located substantially'below the level of the highest tubes 25 (see Figure 2), the holes will serve to more evenly distribute the liquid over the tube ends, although it will be noted that if the device is operated liquid full on the shell side, all of the tubes will at all times be immersed in liquid. Therefore, holes 70 are an optional device provided as a feature of the invention for use in the event that it is desired to regulate for some reason the flow over the tube ends, which flow, it willbe noted, is positively provided by the arrangement which has been described] Viewing Figure 3, together with Figures 1 and 2, liquid or fluid which has flowed'over edge 19 flows downwardly between tube sheet 24 and baffle 16, fills the voids around the tube ends, ultimately reaching the bottom of compartment 20 and flowing around the bottom end 27 of baflle 16. The flow over the tube ends whether solely by flow over end 19 of plate 18 and/or through holes 70 is directly across the tubes. That is, the flow is at right angles to the axis of the tubes. From compartment 20, the fluid passes through compartment 21 around end 28 of the next baflie into compartment 21, etc., until it reaches the similarly shaped device at the right-hand tube sheet 24, following which the flow is essentially the reverse of the flow described for the fluid from the time it enters at 22 to the time it passes over end 19 of plate 18. That is, the fluid passes from chamber 20' (see Figure 1) over plate 18, containing optional holes 70', and out of the exchanger via pipe 23. It will be clear to one skilled in the art that the outlet device at the right-hand end of Figure 1 is a similar structure to the above-described inlet device.

Referring now to Figures 4, and 6, the flow distributor box or device heretofore described in connection with the remaining figures of the drawings is shown in somewhat modified form. Thus, the inlet, or for that matter, outlet, is shown at 54. The plate forming the bottom of the box is shown at 53, the ends of the box are determined by tube sheet 60 and baflle 63, the sides and top are determined by plates 52, 55 and shell 62. In this embodiment, some of the liquid leaves the distributor device at plate end 57 which, for purposes of this description, is capable of flowing the same quantity of fluid or liquid as plate end 19. Additional liquid flows downwardly and around the tubes along extension 53a of plate 53 (see Figure 6) onto closure plate 58 and out through aperture 59 in bafile 51, see Figures 4 and 5, thus joining with liquid which has flowed over the end 57 and flowing together with said liquid through compartment 64, thus, in effect, providing a greater flow of fluid over the two ends than can be provided in the same size equipment as described in connection with Figures 1, 2 and 3, in which the distributor or box has substantially the same dimensions and in which the battles are spaced at the same distances from each other.

The additional outlet just described provides a larger flow with a minimum pressure drop at this section without reducing the number of bafiles by sacrificing baflles near the tube sheet ends. Clearly, in the embodiment of Figure l, the width of edge 19 is determined by the space between tube sheet 24 and baflle 16. Enlargement lengthwise of edge 19 would necessitate reduction of the total number of bafiles which can be provided and would, therefore, for any given rate of flow to the heat exchanger, reduce the rate of flow within the heat exchanger and, therefore, the degree of contact of the liquid with the tubes.

Returning now to Figure 1, it is noted that in the embodiment there shown, fluid or liquid passing through tubes 25 enters inlet 11, passes into chamber 14, through tube sheet 24, passes through tubes 25 to floating header 27' in which it is turned through 180 for its return trip through tubes 25, through tube sheet 24 into chamber 13 from which it exits through outlet 12.

Figure 7, numbered similarly to Figure 1, shows an isometric view, partly broken away, of the shell fluid inlet end of the heat exchanger showing the inlet device of my invention, with arrows depicting the path of flow of the shell fluid.

It will be evident to one skilled in the art in possession of this disclosure that the floating header shown coacts with the end of plate 18 to provide an additional space through which, if desired, liquid can spill down over the tube ends. If such flow is not desired, the batfles or at least the box or distributing device can be made to move integrally with the floating head.

Reasonable variation and modification are possible Within the scope of the foregoing disclosure, drawing and the appended claims to the invention, the essence of which is that there has been provided a device or heat exchanger wherein fluid entering the shell side is conducted to the ends of tubes limited therein and flowed at right angles from one end of the device to the other at all times at right angles to the said tubes by means of a distributor box, as described, in conjunction with bafiles, as described, and similar means have been provided for collecting liquid across the ends of the tubes at the other end of the device and removing the same from the device in flew pattern substantially the reverse of that which the fluid follows when making its entry into the device.

I claim:

1. In a shell and tube bundle type heat exchanger, a shell containing a bundle of tubes, the tube ends being operatively connected to tube sheets, an inlet and an outlet communicating with said tubes, a plurality of batfles alternately extending partially transversely across said tube bundle at spaced positions over substantially the entire length of said bundle to provide a continuous zigzag passage for shell side fluid flowing between said tube sheets, a shell inlet communication at one end of said heat exchanger, a shell outlet communication at the other end of said heat exchanger, said shell inlet and said shell outlet communications being positioned intermediate said tube sheets, at the shell inlet end of said heat exchanger a fluid conducting box disposed between said shell and said tube bundle, said box being in communication with said shell inlet and with the interior of said shell, said box terminating at said tube sheet and being provided with a spill-way opening adjacent said tube sheet to conduct shell fluid which has entered said box through said shell inlet, through said box into an annulus between said tube bundle and said shell in a direction tangential to said bundle and parallel to said tube sheet, said spill-way being defined by said tube sheet, said shell, the nearest one of said baflles, displaced from said tube sheet toward the other end of said heat exchanger, and a curved portion of the bottom of said box extending to one side of said box in a plane substantially parallel with said shell, the end of said nearest bafile, which forms a portion of said zigzag passage, being at the side of said heat exchanger opposite said spill-way, thus conducting fluid passing through said box, between said tube sheet and said transverse batfle, over said spill-way for flow across the tube ends substantially at right angles to the tube axes at the moment of contact of said fluid with said tube.

2. In a shell and tube bundle type heat exchanger, a shell containing a bundle of tubes, the tube ends being operatively connected to tube sheets, a plurality of battles alternately extending partially transversely across said tube bundle at spaced positions over substantially the entire length of said bundle to provide a continuous zigzag passageway for heat exchange fluid, an inlet for fluid communicating with said tubes, an outlet communicating with said tubes, an inlet communication with the shell side of said heat exchanger, and an outlet communication with the shell side of said heat exchanger, said shell inlet communication and said shell outlet communication being positioned intermediate said tube sheets, at one of said communications an open-ended box extending from said communication to a tube sheet at an end of said tube bundle, the open end of said box terminating at said tube sheet at said end, for conducting substantially all of the shell fluid passing through said box between a communication and an adjacent tube sheet, the open end of said box provided with a spill-way defined by the tube sheet at said end of the bundle, the shell of the exchanger, a substantially vertically disposed bafile member displaced from said tube sheet toward the other end of said tube bundle extended between the shell wall and the bottom of said box and by an extended portion of said bottom of said box, the end edge of said extended portion which, in part, defines the open end of said box being in a line substantially parallel with the axis of said tube bundle and at a locus between the tube bundle and said shell whereby the fluid is discharged into an annulus between said tube bundle and said shell in a direction tangential to said tube bundle and parallel to said tube sheet.

3. A heat exchanger according to claim 2 wherein the bottom of said box over the tube ends adjacent the tube sheet is perforated to permit diverting some of the shell fluid flow through the perforations onto the tube ends immediately below said box at right angles to their axes.

4. An exchanger according to claim 2 wherein said tube bundle at at least one end thereof is made with a floating tube sheet and the tube inlet and tube outlet communications for said tube are at the said end of said heat exchanger and said box is, in part, defined by said tube sheet whereby, upon expansion of the tubes, the tube sheet moves away from the remainder of the box to provide a slot opening adjacent the tube sheet.

5. In a shell and tube bundle type heat exchanger, a shell containing a bundle of tubes, the tube ends being operatively connected to tube sheets, an inlet and an outlet communicating with said tubes, a plurality of baffles alternately extending partially transversely across said tube bundle at spaced positions over substantially the entire length of said bundle to provide a continuous Zig-Zag passage for shell fluid flowing between said tube sheets, a shell inlet communication at one end of said heat exchanger, a shell outlet communication at the other end of said heat exchanger, said shell inlet and said shell outlet communications being positioned intermediate said tube sheets, at a shell communication to said heat exchanger a fluid conducting box-shaped spill-way disposed between said shell and said tubes to conduct shell fluid between said communication and a tube sheet at said communication end of said heat exchanger, said box communicating with said communication and being open to the interior of said shell, said box terminating at said tube sheet and being provided with a box-shaped spill-way to conduct a substantial portion of shell fluid from said spill-way into an annulus between said tube bundle and said shell in a direction substantially tangential to said bundle and parallel to said tube sheet, said first spill-way being defined by said tube sheet, said shell, the nearest one of said baflles displaced from said tube sheet toward the other end of said heat exchanger, and a curved portion of the bottom of said spill-way in a plane substantially parallel to said shell, a second box-shaped spill-way to conduct another portion of shell fluid from said spill-way also into said first annulus between said tube bundle and said shell, said second spillway being defined by said nearest baflie, said shell, the next bafide displaced from said nearest baflle toward the other end of said exchanger, and an extension of said curved portion of the bottom of said box-shaped spill-way, in a plane substantially parallel to said shell, the end of said extended portion terminating at said next baffle along the axis of the heat exchanger and at said shell a substantial distance peripherally around said shell from said first spill-way and an opening in said nearest baflie also a substantial distance peripherally around said shell from the end of said first spill-way to conduct shell fluid from said second spill-way into said first annulus.

6. An exchanger according to claim 5 wherein the bottom of said box adjacent said tube sheet over the tube ends between the tube sheet and said nearest baflle is perforated to permit diverting some of the shell fluid through perforations onto the tube ends immediately beneath the spill-way at right angles to their axes.

References Cited in the file of this patent UNITED STATES PATENTS 1,628,487 Bancel May 10, 1927 1,768,786 Potter July 1, 1930 1,979,975 Maniscalco Nov. 6, 1934 2,269,619 Carpenter Jan. 13, 1942 2,363,526 Hobbs Nov. 28, 1944 2,753,954 Tinker July 10, 1956 FOREIGN PATENTS 67,190 Netherlands Jan. 15, 1951