US2003705A - Heat exchanger section - Google Patents

Description

June 4, 1935. J. WHITELEY HEAT EXCHANGER SECTION Filed April 25, 1934 2 Sheets-Sheet 1 OGGGGO R Y w W 4 M mm m W w IIMZ/VA w 5 m M? Y B Z June 4, 1935. J. WHITELEY 2,003,705

HEAT EXCHANGER SECTION Fild April 25, 1934 2 Sheets-Sheet 2 INVENTOR.

James Wfi/le My ATTORNEY.

Patented June 4, 1935 UNITED STAT HEAT EXCHANGER SECTION James whiteley, Detroit, Mich. Application April ,25, 1934, Serial No. 722,402

1 Claim.

of. the invention is to provide a structure through whioh the fluid to be heated is introduced in a cold state and fromwhich it passes in a heated state.

which structure is of a simpleand inexpensive form and in which greater areas than heretofore usual are subjected to the influence of heat, and further a feature and object of the invention is to provide a simplified construction thereby decreasing the manufacturing cost thereof and at the same time exposing maximumsurfacesof the fluid container to heat;

It is'also an object-of the invention to provide a new and improved heater section to be used in a series within .a shell'through which heated gases flow in which sections the fluid to be heated is passed and each of which sections involve a pair of headers and a series of flat tubularelements extending between-the headers and welded thereto, the tube-Walls beingexternally supported against individual. deformation or relative displacement throughinfluenceof pressure or heat... Y a

Itis further an object of theinvention to pro vide a section of the general character above stated in which the interiorsof the tubular elements are open to inspection and free throughout their lengths for introduction of a cleaning implement from the exterior of-thesec-tion. 4

It is also an object of the invention. to provide a heater section having externally. supported tube walls and headers. of a construction to permit ready removal of the tubes therefrom;

These and other objects and the several novel features of the invention are hereinafter more fully described and claimed, and the preferred form of construction of a heater section for use in conjunction with economizers or other purpose is shown in preferred form in the accompanying drawings ihwhich- Fig. 1 is a vertical section of a fuel economizer showing in elevation my improved sections arranged in series. i

Fig. 2 is an enlarged view in .similiar section.

Fig. 3 .is a sectional View taken longitudinally of the section on line 3-3 of Fig. 2.

Fig. 4 is a sectional view showing the sealing plug for the cleanout opening provided in the section. u r

I Fig. 5 is an alternative form of construction showing a means of supporting the tube walls roundtube.

and yet permitting assembly thereof from the tubes. v Fig. 6 is a section taken on line 66 of Fig. 5.

1515 PATENT OFFICE a comparatively ready dis- In Fig. 1 I have shown generally a fuel economizer as one of the purposes of use of my improved heater section construction in which the sections are arranged in series in superposed relation, the lower section I of which is open to a supply line 2 and the successive sections are connected together by U pipe bends 3, 4 etc.

The arrangement of inlet to a section is the bends is such that the at one end and the outlet thereof is on the opposite end and connected to the adjacent end of the next section of the series,

that is, the bend 3 connects the end of the lower section I of the series shown in Fig. l with the adjacent'end of the and the bend 4 conn next section 5 of the series ects the opposite'end of the section 5 with the adjacent end of the section 6 etc., throughout the series and, depending upon the purpose for which the section is used, a considerable number of in the relation stated.

sections may be associated It is to be noted that, in the arrangement of the sections I, '5, 6 etc., the sections are in staggered relation for a In the particular use in an economizer the sec-,

purpose hereinafter stated.

tions are arranged in groups between which is provided a soot blower I, 8 and 9 respectively which forms no part of this present invention. More properly speaking, theinvention resides in the section rather than in the arrangement of the sections for any be obvious that the particular purpose as it will section of the construction and form shown provides a large area in surface contact with heated gases and has a number of observed that these tubes are flat-walled tubes.

By using this form of tube a greater number of tubes may be positioned in a section of a certain length of header than is possible if the tubes were round for instance and further that a greater surface-of tubes is scour ed by the heated gases flowing between the tubes, there being less of the tube at the upper side shielded from the gases by the construction shown 'lhe sections are m than is the case with the ade up of two headers which are originally of channel form having an upper and lower horizontal wall and the outer or end wall I2. The dotted lines I3 in Fig. 2 define the interior end portions of the top and bottom walls. The flattened tubes of the desired length are secured at their opposite ends to the tube plates I4 and I5, which plates are shown in Fig. 3 as forming the inner walls of the headers 9 and III. These plates have apertures fitting the tube, the form in cross section of which is shown in dotted lines in Fig. 2. On the tubes are also provided a series of plates I6, I6 each having apertures through which every tube of the section extends andinwhich the tubes practically fit. These plates I6 are placed in comparatively closely spaced relation on the tubes and extend parallel'with the headers and after these plates are in place, the tube plates I4 and I5 are welded to the tube ends and the plates I 4 and I5 then welded in the headers.

' The plates I6 have a double function. Witha fiat tube, pressurewithinthe tube tends to de-' form the walls and the plates thus serve to prevent such deformation by internal pressure. Further, the tubes being subjected to heat and being of comparatively thin metal, the tube itself tends to warp or become displaced relative to the other tubes intermediate the ends. Each of these plates I6, which are shown in dotted lines in Fig. 2, enclose the entire group of tubes in a section and serve to prevent or limit any material relative displacement of the tubes through heat so at all times the tubes are maintained throughout their.

arecontinuously deflected'as they pass upward" through the various sections and the maximum heat is absorbed from the gases in flowing over the sections. In this respect it will be readily noted that the hot gas stream passing between two tubes of a lower section has the sides of the gas stream in contact with said tubes and the central portion of the gas stream beingout of direct contact with the first two tubes has lost less of its heat than the portions in contact with the tubes and this more highly heated central portion of the heated gases is directed against the lower side of an upper tube and caused to take a path upwardly around its side walls and thus continuously the hottest portion of the gases are deflected to contact with the wall of the tubes carrying the fluid to be heated. v I

' In the construction of a fuel economizer such as is'herein suggested, the sections may be supported by angle irons I1, I! on opposite side walls and a deflector or baiile I8 is provided at one end of one section and at the opposite end of the next section throughout the series which arrangement in sures the positioning of the sections in the stagg'ered or offsetreiation above described. The baffie prevents passage of any material portion of the gases around the sections. I

It will be noted that the tubes are free from internal obstruction and open to the headers and, as shown in Fig. 2, there is a plug I9 provided in the outer wall I2 of each header for sealing the aperture which is of a diameter in the construction shown, suificiently large to provide access to three tubes through which a cleaning implement may be passed from the exterior of the headers. In Fig. 1 is shown a series of plugs I9 (the blank holes simply diagrammatically representing the plugs) and an opening of approximately the same diameter is provided for the connection of the conduits 2, 3, 4 etc. Such conduit as is illustrated at 3 in Fig. 2 being on the end of the section opposite the end provided with the plugs shown on the left side of the said figure. On theright side is shown the ends of the conduits connecting the sections shown in Fig. 2 with the section below the lower section and the section above the upper sec-- tions.' The preferable form of plug for use in the headers is shown in Fig. 4. It consists of a tapered member 20 having a threaded stem 2|. A packing ring 22 is provided in the aperture and a plate 23 provides a cover for the aperture through which the stem extends and which cover maybe integral with the nut if so desired. By turning the nut the tapered plug is drawn down against the packing ring and seals the opening.- Also, the taper of this plug is such that'internal pressure within the header tends to seat the plug. Other forms of plug maybe used, however, without departing from the spirit of this invention. I

The fuel economizer shown simply consists of a shell 25 having an opening 26 at the bottom through which heated gases may pass as for instance from a boiler, and a hood 2'! is provided at the top for an'exhaust stack but this general character of construction is simply diagrammatic. The upper section of the series also has a relief valve 28 provided thereon and is connected to a pipe line 29 which may lead to the boiler or other apparatus to which the heated fluid is to be discharged. A blow-off valve 30 may be provided.

1, In the construction. as hereinbefore described and with the plates I6 mounted on the tubes II in which they are practically a press-fit, it is diiiicult'to withdraw a tube from the headers and while there are many constructions in which such an arrangement is desirable and practical there are a number of installations where it is desirable that the tubes be readily removable. For this purpose I have shown in Figs. 5 and 6 a means for supporting the walls of the tube from deformation by internal pressure that is capable of being disassembled from the tubes. The header is shown in Fig. 5 at I2 and the tubes are shown at I I in section. Above and below the tubes are the bars 30 and 3I which support the plates 32, as shown in Fig. 6, that extend from one bar to the other in contact with the side walls of the tube. The plates or bars 32 have the U ends 32* to loosely receive the bars 30 at one end and 3| at the opposite end as shown in Fig. 6.

The bars 30 and 3I are threaded at the ends and the ends extend through apertures in an end plate or bar 33. Nuts 34 on the ends of these bars 30 and 3I are utilized to tighten up the entire structure holding the tubes in pressure contact with the. alternate plates or bars 32 whereby they. are supported from deformation by internal pressure. These bars 30 and 3I are spaced'apart similarly to the plates I6 of Fig. 3 and thus there area series of plates or bar like members 32 at short distances apart longitudinally of each tube II and the same purpose is achieved by this latter construction as attained by the construction described relative to the structure shown in Fig. 3.

It will be seen from the foregoing description that the invention resides in the construction of the heater section and that the various objects of the invention are obtained by the construction described, namely, a comparatively simple and inexpensive heater section which is highly efiicient in use due to the form of the tubes and the manner in which the tubes are supported against distortion or displacement through pressure or heat; that the sections are readily cleaned and that, by arranging the sections in staggered relation, a highly eflicient heating system for fluid is obtained and also that the metal plates on the tubes materially assist in transferring heat to the fluid in the tubes.

Having thus briefly described my invention, its utility and mode of operation, what I claim and desire to secure by Letters Patent of the United States is-- A heater section for use in boilers, fuel econ-V omizers and the like comprising a pair of headers a series of tubes opening at opposite ends to the respective headers, a series of plates separating the tubes and lying in contact with the side walls thereof and in spaced relation longitudinally of the tubes between the headers, and means for applying pressure to the series of plates and interposed tubes whereby the plates through contact with the side walls of the tube under pressure prevent deformation of the tubes through internal pressure.

JAMES WHITELEY.

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