US1978897A - Tubular heat exchange device - Google Patents

Description

Filed July 1, 1953 2 Sheets-Sheet 1 mmrm/P 44 MM 24 A17 0mm.

Oct. 30, 1934. IE 1,978,897

TUBULAR HEAT EXCHANGE DEVICE Filed July 1, 1933 2 Sheets-Sheet. 2

f lam T01? 447 w wzgMw fm Patented Get. 3@, 1934 TUBULAR HEAT EXCHANGE DEVICE Harvey Feldmeier, Little Falls, N. Y.,

Cherry Burrell Corporation,

assignor to Wilmington, Del.,

a corporation of Delaware Application .l'uly 1, 1933, Serial No. 678,633

12 Claims.

This invention relates to improvements in tubular heat exchange devices for fluids, and more particularly to internal tube or double tube heat exchangers of that type used for heating 5 or cooling liquids such, for example, as milk, in Which the liquid or milk flows through inner tubes arranged within outer tubes through which flows the water or other medium for heating or cooling the milk or liquid. The tubes in devices of this type are commonly arranged in banks side by side or one above another, the internal tubes being connected at their ends by returns or headers to form a continuous zig-zag coil or conduit for one medium, and the outer tubes being likewise connected at their ends by returns or headers to form a continuous coil or conduit for the other medium. In order to insure complete draining of the fluids from the tubes of exchangers of this sort in which the connected tubes are disposed in diiferent banks, it is usual to incline the tubes of adjacent banks in opposite directions, and also incline the con necting passages of the returns or headers so that the tubes and returns or headers will thus form a continuously inclined or descending conduit or passage for each fluid or medium.

Double tube heat exchangers of this character have been extensively used for many years, but long and varied experience has shown that such 30 devices, as heretofore constructed, are open to various objections. This type of apparatus is subject to severe strains set up by unequal expansion and contraction in different parts thereof, due to temperature changes, and these strains 35 cause leaks and bow or spring the tubes so as to interfere with their proper operation. For instance, in the use of such apparatus for treating the milk, they may be subjected at times to a cold milk temperature of say 50 F. and a 40 sterilizing temperature of 290 F., or a temperature change of 150. The expansion or contraction of the tubes in a twelve foot section under such a temperature change exceeds one-quarter of an inch and unless the apparatus is con- 'structed so that the parts are free to take care of this movement in the tubes, which may be unequal in difierent parts of the coil or section, serious strains will be set up tending to bend or spring the tubes or loosen the joints.

One object of this invention is to produce a tubular heat exchanger of the sort mentioned of improved construction which will overcome objections to previous constructions.

Other objects of the invention are to produce a practical and efficient tubular heat exchanger for fluids, of novel construction; also to provide such a device in which the section or coil is made up of tube units grouped together in a flexible way so that the whole coil or any part, thereof is free to expand or contract without setting up undue strains in any part; also to join the tubes in an endless coil or conduit which is mounted on its supporting stand or structure so that the coil is free to expand or contract as if it were a long straight tube held at one end only; also to provide a support or stand of novel construction for heat exchange coils or sections which will adapt itself to unequal expansion and contraction or inequalities in the parts of the coil or section and will enable a more ready mounting of the coil or section on the stand or support; also to make a tubular heat exchanger of a construction which lends itself to economy in material, enabling a high grade apparatus to be produced at moderate cost; also to construct an apparatus, including the tubular coil or section and the support therefor which will be of neat, attractive appearance; also to provide a construction that allows any number of tubes, odd or even, in the coil or section, and makes it convenient to add or subtract tubes in installations in the field; also to provide individual returns for each pair of inner or outer tube ends, thus making it possible to have fluid connections for either the inner or outer tubes at any number of points in the coil or section necessary to give greatest eihciency; also to provide a construction by which the coil or section can be made with an even or odd number of tubes so that the inlets and outlets for the two fluids can be located at the same end of the coil or section or at opposite ends thereof; also to construct the coil or section with glanded connections between the tubes and returns so that the entire assembly is demountable and solder joints between the tubes and returns or headers are avoided. This is of particular advantage where chrome nickel steel tubes or other tubes that cannot be readily soldered are used. Also to provide a stand or support that holds the coil or section securely in place but is practically invisible; and also to produce a tubular heat exchanger whichhas the other features of improvement and advantage hereinafter described and set forth in the claims.

In the accompanying drawings:

Fig. 1 is a side elevation of a tubular heat exchanger embodying the invention.

Fig. 2 is an end elevation thereof, partly in section, on line 22, Fig. 1.

headers with liquid tight joints.

Fig. 3 is a transverse sectional elevation of one of the tube seats or saddles.

Fig. 4 is a side elevation thereof.

Fig. 5 is a broken longitudinal section through one of the double tubes and outer tube returns.

The double tube heat exchanger illustrated in the drawings comprises outer tubes 10 arranged in two banks, one in front of the other, with the tubes of each bank arranged one above another, andthe tubes in the different banks oppositely inclined, and a series of inner tubes .11, one extending concentrically through and spaced from each outer tube. The outer'tub'es are joined to form a continuous coil or conduit by returns or headers 12 at the opposite ends of the tubes,

each header 12 connecting "one end of a tube in one bank with the corresponding end of an adjacent tube in the other bank. Preferably these returns or headers 12 at opposite ends of the coil or section are oppositely incline-d, as shown, so that the connected tubes 10 .and headers .12 form a continuously inclined conduit or passage. The adjacent returns .12, or those at corresponding .endsof the tubes, are separate from .and movable relatively to each other. The inner tubes 11 preferably are similarly connected to .form a single continuous coil or conduit by .re-

turns or headers 13, each of which connects an inner tube inone bank with an adjacent inner tube .in the other bank. These returns 13 also are oppositely inclined at opposite ends of the tubes so that the .innerlcoil or conduit inclines continuously in .one direction.

The outer tubes 10 are removably secured to the headers 12 preferably as shown in Fig. ,5,

the tube .10 being providedadjacent its ends with circumferential beads .or projections .14 which are clamped between seats 15 in the headers and annular packings 16 adapted to be .compressed by adjustable glands 17. which, as shown, are

screwed into the threaded openings in the head- .ers which receive the ends of the tube 10. By screwing up the .glands 17, the packings .16 are compressed and clamp .the beads 14 against the seats, thereby firmly securing the tube to the While the headers are thus rigidly secured on the ends of the tubes and move therewith in the expansion and contraction of the tubes, nevertheless the headers .can .be readily disconnected from the tubes by unscrewing the glands 17.

The inner tube 11 ineach outer tube extends out through headers 12 at opposite ends of the outer tube and the joints between the inner tube and the outer headers 12 are made liquid-tight =bysuitable packing means, such .as packing rings .18 compressed between seats 19 in the headers 12 and glands 20 screwed into threaded holes in the headers 12,01" otherwise .adjustably connected to the headers, see Fig. .5. Preferably, as shown in .said figure, the inner tube is firmly but detachably secured in one return 12 by a circumferential collar .or flange 21, fixed by sweating .or otherwise, on the inner tube and clamped between the gland packing 1.8 and the seat 19 in the return. 12. By this construction the inner tube is rigidly secured near one end in one return 12 and the other end of the inner tube is adapted to move lengthwise in the packed joint in the opposite return .12 to'allow for any relative movement between these parts due to diffierential expansion and contraction in the bered to form a connecting passage 22 between reason of any differential expansion and contraction indifferent portions of the coil or section. Otherwise, the returns or headers may be of :any suitable construction and preferably the returns 13*for the inner tubes are made with the usual hinged covers 23 which can be readily opened to afford access for cleaning the inner tubes. The returns 13 are also detachably secured to'the tubes 11.

As usual, the internal coil is suitably equipped at its upper and lower ends for connection with supply or discharge pipes 25, 26 for milk or other and the outer coil is provided at its opposite ends with suitable fittings .27 and 28 for the .adrnlssion cr'discharge oi the water, brine or other medium whichjis circulated through the outer coil. in addition, any one or more of the intermediate returns '12 for the outer tubes can be replaced by a chambered header or fitting 30, see Figs. .1 and2, whichis provided with a dividing wall or partition between the ends of the tubes connected by this header, which is suitably formed for the connection therewith oi admission and discharge pipes 81, .32 so that one heatingor cooling medium, such as water, can be circulated through one portion of th section or coil,

and a different medium, such as brine or water of a di erent temperature, circulated through another portion of the c'oilor section to make a .multiplestage heating or cooling coil.

The described construction, having the separate or independent headers 12, makes it possihis to interpose one or more of the inlet andoutlet headers 30 at any desired point or points in the coil so as to divide the coil into two or more stages or portions of any desired number of tubes.

The coil .orsection, comprisingtu'bes connected by separate, independently movable headers or returns, as described, is mounted on a stand or support, preferably formed by connected uprights or posts 35, 36 arranged between the front and rear banks of tubes and provided with suitable feet or bases27 and with forwardly and rearwardly projecting seats on which the tubes of the two banks rest and are supported. As shown, the pos s 35 and 36 are rigidly connected by crossed diagonal brace rods 38 suitably fastened at their ends to the posts or uprights. Each tube seat is preferably formed .by a saddle 39 having a concaved segmental cylindrical top face ii) on which one outer tube 16 rests and which conforms substantiefily to the curvature of the Itubeand each saddle has a transversely grooved bottom or portion 41 which straddles and is adapted to rock on a stud 42 fixed to and projecting forwardly or rcarwardly from the post or upright. The outer tube rests loosely in the concaved seat are and is adapted to :slide lengthwise or turn therein any movement of the tube, due to expansion or contraction thereof, and the saddle is adapted to rock on the stud 42 in a vertical plane extending longitudinally of the tube and also to slide or shift on the stud, in a direction Mil -ner tubes extending through said outer tubes and transverse to the tube. Each tube thus has a substantially universal rocking and sliding support on each upright. This manner of mounting the saddles or seats on the support or stand enables them to readily adapt themselves to the inclinations or positions of the tubes which they support and provide extended bearings for the tubes which, while they firmly support the coil or section, nevertheless permit relative movement between the section or parts thereof and the stand. The movable saddles thus insure amply large bearing surfaces for the several tubes notwithstanding possible irregularities or inaccuracies in the inclinations or positions of the tubes due to inaccuracy of manufacture or changes in position'due to expansion and contraction of the tubes in operation. This result could not be secured by rigid or fixed seats for the tubes except by careful and much more expensive machine work, so that the stand with the movable saddles or bearings for the tubes can be produced at less expense and labor than a stand having rigid bearings or seats giving correspondingly extended bearings for the tubes.

The coil or section is secured at one point only in its length to the stand or support. For example, the free end of the uppermost tube of the coil is anchored, as by a rod 45, to the adjacent upright or post 35, but otherwise the section simply rests loosely on the tube saddles 39. Therefore, while the saddles retain the alinement of the tubes in the banks, the section is secured only at one point to the stand and the section as a whole or the various portions thereof are capable of movement relatively to the stand which prevents any binding or strain on the coil or stand or the parts thereof.

I claim:

1. A tubular heat exchanger for fluids comprising a series of outer tubes, returns connecting said tubes to form a continuous outer conduit, inner tubes extending through said outer tubes and returns and joined to form a continuous inner conduit, said returns being separate and independently movable relatively to each other under expansion and contraction of the tubes, a support for said heat exchanger provided with seats having supporting surfaces of extended area on which said outer tubes rest movably, and means for retaining said heat exchanger in place on said support but leaving the heat exchanger free for movement relatively to said support under the expansion and contraction of said tubes, said seats being mounted to shift on said support in conformity with changes in positions of said tubes.

2. A tubular heat exchanger for fluids comprising a series of outer tubes, returns connecting said tubes to form a continuous outer conduit, inner tubes extending through said outer tubes and returns and joined to form acontinuous inner conduit, said returns being separate and independently movable relatively to each other under expansion and contraction of the tubes, a support for said heat exchanger having seats of extended area on which the several outer tubes rest movably and which have bearing contact with substantial surface areas of the tubes, and means connecting said heat exchanger at one point to said support and leaving said outer tubes free to move on said seats under expansion and contraction of the tubes, said seats being mounted onsaid support for movement relatively to each other.

3. A tubular heat exchanger for fluids comprising a series of outer tubes, returns connecting said tubes to form a continuous outer conduit, in-

. traction of said tubes.

returns and joined to form a continuous inner conduit, said returns being separate and independently movable relatively to each other under expansion and contraction of the tubes, a support for said heat exchanger provided with seats which have bearing contact with relatively extensive areas of said outer tubes and on which the tubes rest movably, and means connecting said heat exchanger at one end only of said conduits to said support and leaving said outer tubes free to move on said seats under expansion and contraction of the tubes.

4. A tubular heat exchanger for fluids comprising a series of tubes, separate returns con necting said tubes to form a continuous zig-zag conduit, a support for said heat exchanger pro vided with seats which have bearing contact with relatively extensive surface areas of said tubes and on which the several tubes rest movably, means for securing said heat exchanger at one end only of said conduit to said support and leaving said tubes free to move on said seats under expansion and contraction of said tubes.

5. A tubular heat exchanger for fluids comprising a series of tubes, separate returns connecting said tubes to form a continuous zig-zag conduit, a support for said heat exchanger having seats on which the several tubes rest movably, said seats being capable of pivotal movement on said 105 support in the planes of said tubes, and means for securing said heat exchanger at one point only thereof to said support and leaving said tubes free to move on said seats under expansion and con- 6. A tubular heat exchanger for fluids comprising a series of tubes, separate returns connecting said tubes to form a continuous zig-zag conduit, and a support for said heat exchanger having seats on which the several tubes rest movably, said seats being movable on said support in the planes of said tubes and also in planes at right angles to said tubes, whereby said tubes are free to move relatively to each other under expansion and contraction of said tubes while reg maining in place on said seats.

7. A tubular heat exchanger for fluids comprising a series of tubes, separate returns connecting said tubes to form a continuous zig-zag conduit, a support for said heat exchanger provided with pivoted seats on which each of said tubes rests movably to provide a substantially universally movable connection for each tube with the support, and means for securing said heat exchanger at one point only thereof to said support and leaving said tubes free to move on said seats under expansion and contraction of said tubes.

8. A tubular heat exchanger for fluids comprising a series of tubes, separate returns connecting said tubes to form a continuous zig-zag conduit, an upright support for said heat exchanger provided with laterally projecting studs, saddles pivotally movable on said studs and each movably supporting one of said tubes, and securing means which retain said tubes on said saddles.

9. A tubular heat exchanger for fluids comprising tubes arranged in spaced-apart banks, separate returns connecting the tubes to form a continuous conduit which is formed in part by the tubes in each bank, an upright support for M5 said heat exchanger arranged between said banks of tubes and provided with laterally projecting seats on which the tubes of one bank rest movably and with oppositely projecting seats on which the tubes of the other bank rest movably, said 15g seats being relatively movable to accommodate their positions to different positions of the tubes.

10. A tubular heat exchanger for fluids comprising tubes arranged in parallel banks with the tubes in different banks oppositely inclined, separate returns connecting the tubes to form a single continuously inclined conduit, an upright support for said heat exchanger arranged between said banks of tubes and provided with laterally projecting seats on which the tubes of one bank rest movably and with oppositely projecting seats on which the tubes of the other bank rest movably, said several seats being relatively movable.

11. A tubular heat exchanger for fluids comprising tubes arranged in parallel banks with the tubes in difierent banks oppositely inclined, returns connecting the tubes to form a continuous conduit, a supporting stand for said heat exchanger comprising connected uprights arranged between the banks of tubes, seats projecting lat- .erally from said uprights for each tube in one bank, and seats projecting oppositely from said uprights for each tube in another bank, said tubesresting movably on said seats, said seats being mounted for movement relatively to each:

other and means movably retaining said tubes in place on said seats.

12. A tubular heat exchanger for fluids comprising a series of tubes, separate returns connecting said tubes to form a continuous zig-zag conduit, a support for said heat exchanger having seats on which the several tubes rest movably,rsaid seats being mounted to shift on said support in conformity with changes in positions of said tubes, and'said tubes being free to move on said seats and being movable relatively to each other under expansion and contraction of said tubes.

HARVEY FELDMEIER.

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