US1831337A - Heat interchanger - Google Patents

Description

Nov. 10, 1931 c. K. BENNETT HEAT INTERCHANGER 2 Sheets-Sheet 1 Filed Jan. 27. 1928 Gitonwq Nov. 10, 1931. c. K. BENNETT HEAT INTERCHANGER Fi led Jan. 27, 1928 2 Sheets-Sheet 2 3714x144 01, 676771622? 71 .Bevmefi Patented Nov. 10, 1931 UNITED- STATES PATENT OFFICE CLEMENT K. BENNETT, OF BUFFALO, NEW YORK, ASSIGNOR TO 0. E. FRANK HEATER &

ENGINEERING 60., INCL, OF BUFFALO, NEW YORK, AQORIORATION OF NEW YORK HEAT INTERCHANGER Application filed January 27, 1928. Serial no. 249351.

This invention relates to improvements in heat interchangers and more particularly to the type of construction which includes a shell having a heat exchange chamber which is provided with inlet and outlet openings for the flow of one of the fluids and tubes arranged in said chamber to provide a path for the flow of the other fluid, the inlet and outlet openings of which are formed in a main header at one end of the shell.

An object of the invention is.to provide :1 construction wherein the tube nests are accurately centered in the chamber and from which they may be removed as a unit without requiring any pipe connections to be broken.

Another objectis to provide transverse bafiies of a form and arrangement such that the formation of vapor pockets between the baffies and around the tubes .is prevented thereby .to maintain the entire tube surfaces active at all times.

A further object is to provide sediment pockets in which the sediment may accumulate for considerable time before decreasing the efiiciency of the unit and to provide means which will enable the pockets to be slushed from time to time without necessitating the dismantling of the unit.

An embodiment of the invention is illustrated in the accompanying drawings, where- 1n:

Figure 1 is a longitudinal sectional view of the unit at right angles to the main bafile plate.

Figure 2 is a sectional view along the line 22 of Fig. 1 with the bafie plateand main header partition removed.

Figure 3 is an end view of the main header end of the unit with the cover removed.

Figure 4 is a sectional view of the casing taken along line 44 of Fig. 1 with a transverse baflle plate partly broken to show the arrangement of such bafiies more clearly.

Fi the joint formed by the tube sheet with the main header end of the shell and showing the centering means.

Figure 6 is a front elevation of one of the transverse bafiles.

re 5 is an enlarged detail section of {end of the shell by a tube sheet or As stated before the unit essentially includes a casing or shell 1 which delimits a heat exchange chamber 2. The shell is,

formed with one set of fluid inlet and outlet openings 3 and 4 respectively, preferably arranged opposite to eachother adjacent to one end of the shell, these openings being, of course, in open communication with the chamber 2. This end of the shell is preferably enlarged to provide a main header 5 which is formed with a set of fluid inlet and outlet openings 6 and 7 for the other fluid.

The path of the fluid passing through the I openings 3 and 4 is defined by a main baffle 8 and a set of transverse bafiles 9. The main bafie 8 is longitudinally placed within the chamber so as to compel the fluid to travel along one side of the baflie from the inlet opening 3 to the opposite or floating head end of the shell returning along the other side of the bafie to the outlet opening 4. The transverse loafies 9 are placed transversely m,

to have edge abutment with both the main *bafie 8 and the wall of the chamber 2 and in a zig-zag manner along the path defined and at intervals along, the path defined by the main battle 8, these baffles being shaped and to this end alternate bafies are cut away a at one side and the remaining bafies cut away at the opposite side, the cut away portions being in the form of a segment as indicated at 10. It is understood, of course, that the main bafie is cut away at the floating head end of the shell to permit the fluid to pass from one side of the bafie to the other, the

cut away portion being located at that side of the shell remote fromthe cut away portion 10 of the adjacent transverse battle 9,,so

as to continue the zigzag flow at this end.

The path for the other fluid, as illustrated,

includes two tube nests 11 which are placed longitudinally in the chamber 2 on opposite sides of the main baflle 8, the tubes being fitted in suitable apertures formed in the transverse baffles 9. The tubes of each nest are preferably supported at the main header plate 12 shell. In order to center the tubes accurately within the shell and at the same timeinsure a tight joint, the plate 12 is formed with a raised portion 1a which extends slightly into,

and fits closely against the walls of, the chamber 2. The opposite side of the plate is formed with a wallor partition 15 which extends into the main header 5 dividing it into two compartments A and B which cornmunicate respectively with the inlet and outlet openings 6 and 7. The tubes 11 pass through the plate 12, the tubes on one side of the baffle 8 communicating with the chamber A and the tubes on the other side of the bafie communicating with the chamber B. The construction of this end of the unit is completed by a cover 16 which provides an end closure for the main header 5. It will be understood, of course, that, if desired, the partition 15 may be made integral with the cover instead of the plate or tube sheet. In any case the partition extends into recesses or grooves in the adjacent walls to seal the chambers A and B with respect to each other The opposite end of both nests of tubes is embedded inand passed through the ad acent wall 17 of a floating'head and communicate with the chamber 18 formed by said head. Thischamber functions to bring the tube nests in communication with each other and also to provide a pocket for the accumulation of any sediment settling out of Y the fluid. The pocket is made comparatively deep so as to permit considerable accumulation of sediment, and thus arelatively long period of operation, before the flow becomes obstructed sufliciently to decrease the efliciency of the unit. ,T he floating head has an end closure or cover 19, the margin of which is formed with a flange 20 which fits into a corresponding recess in the adjacent end of the head so as to insure against leaking or blowing at the joint. The cover 19 is also provided with a removable plug 21 which,

when removed, permits the accumulated sediment to be slushed out from the main header end, without requiring the dismantling of the unit, it being noted that the main header cover is also provided with removable plugs as 19a, one for each compartment in the header.

This,end of the shell, that is to say the floating head end, is closed by acover 22 which is dished and spaced from the floating head to provide a sediment pocket for the fluid passing around the battles. The cover 22 is also provided with removable plugs 23 and 24' which permitthe accumulated sediment to be observed and slushed out as desired.

From the foregoing, it is apparent that any fluid passing through the inlet opening 3 must travel in a zigzag path along one Side of the main batfle until it reaches the opposite end of the shell whence it passes around the end of the main baflie and returns in like manner to the outlet opening 4. In connection with the fluid path thus defined, it is noted that when the unit is placed vertically, no vapor pockets can be formed between the transverse batfles 9 and around the tubes. If, however, the unit is placed horizontally in a manner such that the main battle 8 lies in a horizontal plane, the formation of vapor pockets in that part of the path located above the main baflie, will result if the highest point of the cut away portions 10 is substantially below the crest or uppermost part of the wall of chamber 2. To avoid such formation and to maintain the entire tube surfaces active at all times. the cut away portions 10 i of this unit may, if desired, be made to extend to the uppermost part of the shell thereby eliminating the formation of vapor pockets entirely but preferably are made to extend sufliciently high to prevent any appreciable formation as, for instance, to apoint where the inertia of the fluid as a whole, causes the fluid tending to remain in a pocket to he carried along with the main body of fluid.

The other fluid passing through the inlet opening 6 and the adjacent chamber A, must travel through one nest of tubes to the chamber 18 of the floating head, returning through the other tube nest to the chamber B whence it passes through the outlet opening 7.

When it is desired to remove the tube nests for the purpose of inspection, cleaning or repair, this may be accomplished merely by removing the cover 16 and the bolts by which the tube sheet 12 is secured to the shoulder 13 of the shell. The tube nests 11 together with the tube sheet and floating head may then be withdrawn from the main header end of the shell as a unit and without in any way. disturbing the pipe connections of the unit located at the main header end of the unit or Without disturbing the floating head of the unit. Having described the invention, I claim:

1. In a heat interchanger of the class described, the combination with a casing formed with an end portion of increased diameter to provide an end chamber adjacent its main chamber and having two sets of fluid inlet and outlet connections, one set of which is formed in the side wall of the end chamber portion ofsaid casing of a unit bodily insertible in or removable from the main chamber of said casing through said end chamber, said unit including'a plurality of tubes and baflies respectively arranged to provide heat interchanging fluid paths be-,

tween said sets of inlet and outlet connections, a removable cover plate for the open end of said end chamber and a partition removable from said casing, said partition being adapted to divide said end chamber into inlet and outlet compartments.

2. In a heat interchanger of the class described, the combination with a casing longitudinally delimiting a heat exchange chamber andan end chamber and formed with inlet and outlet openings for each chamber, of a unit bodily insertible in and removable from said casing through'the said end chamber, said unit including a partition adapted to divide said end chamber into inlet and outlet compartments, a plurality of tubes adapted to provide a fluid path between-said compartments and a plurality of battles adapted to prescribe a path of flow around said tubes and between the fluid inlet and outlet openings of said heat exchange chamber.

3. In a heat interchanger of the class described, the combination with a casing having removable end closures and longitudinally delimiting a heat exchange chamber and an end chamber, said casing being formed wit-h inlet and outlet openings for each chamber, of

a unit bodily insertible in and removable from said casing through said end chamber, said unit including a tube sheet adapted to be securely fitted 1n said'casing'and separatlng one chamber from another, a partition extending from one side of the sheet and adapted to divide said end chamber into fluid inlet and outlet compartments, a plurality of tubes adapted to provide a fluid path between said compartments. said tubes extending through said sheet and into said heat exchange chamher. and a plurality of baflles adapted to prescribe a fluid path around the tubes and between the fluid inlet and-outlet openings of -with said sediment pocket, said tubes providing a path for the flow of one of the fluids, battles arranged to provide a path around and between the tubes for the flow of the other fluid, and. means permitting the sediment pocket and the tubes to be slushed from the opposite end of said casing upon the removal of said end closure and plug. a

5. A heat interchanger comprising a'casing having an outwardly dished end closure, :providedwith at least two removable plugs, a member formed with a chamber and transversely arranged in saidcasing adjacentto said end closure, a plurality of tubes longitudinally disposed in said casing and communieating at one end with said chamber, said tubes providing a path for the flow of one of the fluids, and bafiles arranged around said signature.

tubes and prescribing a path for the flow of a longitudinally disposed on either side of said baffle plate and providing a path for the flow of the other fluid, and segmental bafiies arranged transversely of said casing and tubes at intervals along said first mentioned fluid path to compel the fluid to travel in a zigzag manner, each segmental baffle having an aperture of such a height that it extends above the highest tube when the main baflie plate is-in a horizontal plane whereby the formation of vapor pockets is avoided and the entire tube surfaces maintained active.

7. In a heat interchanger of the class described, the combination with a casing having two sets of fluid inletand outlet connections, one set of which is formed adjacent to one end of said casing, of a unit bodily insertible in or removable from said casing and through said end without disturbing the. ex- I terna'l fluid connections to said casing, said unit including a main balfle plate longitudinally interposed in said casing and prescribing a path for the How of one of the fluids, a

plurality of tubes longitudinallydisposed on either side of said baflie plate and providing a path 'for the flow of the other'fluid, and

segmental baflies arranged transversely [of said casing and tubes at intervals along said first mentioned fluid path to compel the fluid to travel in a zigzag manner, each segmental baflle having an aperture of such a height that it extends above thehighest tube when the main baflle plate is inia horizontal plane whereby the formation of vapor pockets is avoided and the entire tube surfaces main-- tained active.

In testimony whereof I- hereby aflix'my CLEMENT K. BENNETT.

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