US2118060A - Finned tube - Google Patents

Description

Petented May 24, 1938 UNITED STATE FINNED TUBE R. Harry Stone, Bound Brook, am! Edwin F. Tilley, Dunellen, N. J., assignors to Titeflex Metal Hose 00., a corporation of New Jersey Original application July 26, 1930, Serial N0.

Divided a.nd this application Octobei 4, 1933, Serial N0. 692,088. Renewed Allgust 24, 1937- 8 Claims. (GI. 257262) This lnvention relates to tubes and has special referenee to the transfer of heat to or from the seme. 1

The pisent appllcation is a dlvlsion of nur application Serial Number 471,034, filed July 26, 1930 which has since matured into Patent N0. .1941587 dated January 2, 1934.

'Ihe mein object of the invention is to provide improved means for effectingyfiransfer of heat to -or from the tube--from the taube when it is desired to dlsslpate heat from the contents of the tube as is the case with radlators heaters and the like, and from the surrounding medium to vention to provide the improved heat exchanging means incor mection with a corrugated taube.

It is a f1'1rther and ancillary object of the inven- .tion to provide-a;he'at transferring fin inconnection with a corrugated taube.

It is a further object of the inventionto a heat transferrlng fin in connection with a corrugatedisube formed from a grooved st rip hellcally disposed and having the edges of adjacent convolutions secured together whereby the canstruction and processes of manufacture are greatly lmproved.

A further and 4ancillary object of the inventlon is to provlde an improved constructioh of finned tube.

Other and a ncillary objects of the invention will appear herelnafter.

In the accompanying drawlng which illustrates the invention- Fig. 1 ls a. v1ew, partly in slde elevation and partly in section, of a structure of corrugated tube embodying the inventlon;

Fig. 2 is a viewpartly in elevation and partly in section, 01 a modified form of tube'embodying the invention;

Fig. 3 is a vlew, partly in side elevation and partly in section, of a still further modified structure of taube embodying the invention;

Fig. 4 is a view, partly in side elevation and partly in section, of a still further modified structure of taube embodylng the lnvention; und.

Flg. 5 is a view, partly in side elevatlon am]. partly in sectlon, of a. still further modlfled structure of tube embodying the inventlon.

F-eferring tq the drawing, and first to Fig. 1, there is therein shown a. corrugated tube wlth the heat exchange fln mounted upon the outer s1de of the corrugation. The efliclency 01 the taube a.s' a

Drovide heat exchanger may be very greatly increased by combining the corrugation with a fin upouthe outslde thereof over what could be accomplished with either the corrugation or the fin alone. The corrugation increases the radiating surface of the tube exposed to the air and so increases its radiation. Upon making the corrugations too high, however, the pocketing 015 air between the corrugations is very largely lncreased so that there is more eflicient radiation if the corrugations are made of moderate depth and a fin of heat-conducting mate'rial is supplied on the outside' of the corrugation. Also the use cf the corrugation in combination with the fin on its outside is more efficientthan depending upon the height pf the corrugation to give the desinad. heat exchange, for the reason that if the corrugation is ma.de too hlgh the heated fluid in bassing thr0ugh the tube is apt to not penetrate into the extreme recesses of the corrugations so that radiatlon from the outer surface of the corrugation 1s impaired, whereas if the corrugation is'made low the heated fluid within it penetrates fully throughout the corrugation and delivers 1cs heat thereto, the fin at the outslde'of the corrugation a.ctlng 1:0 conduct awajy such heat and dissipate it into the surroundln'g atmosphere. -Also it is desired to limlt the helght 01 the corrugation and combine it wlth a. fin as described, because a corrugation of too gre.t height, under some circumstances, too greatly retards the flow of heated fluid through the taube; v

In Flg. 1 the strueture includes a tube formed from a helically disposed strip of metal having the edges cf adjacent convolutions interfolded as in the patent of the United Staates of America to Louis H. Brinkman N0. 1,198,392 patented September 12, 1916, and having the corrugations 56, the fin being .provided by a helically disposed metal strip having -a right-angled section comprising the radial portion 51 and the foot portion the groove between the corrugations and does not flow freely away so that the radiation or dissipation cf the hea.t Irom the tube is impa'ired. Thls. conditlon may be greatly improved and the corrugated tube as a radlator ofheat may be improved, by placing a metal or other heat conducting fin within the space between the corrugatlons. This conducts the heat away from lts confined space and largely lncreases the heat radlatlng capacity of the tube by relievlng the congestion of heat which occurs in the space between the cor'- rugations.

A device embodying this conception is shown in Fig. 2 of the drawing, wherein the corrugated tube 43 is formed by helicallydi'sposing a metal strip hav ing a longitudinal groove and. interfolding the edges of adjacent convolutions as described in the Brinkman patent hereinbefore referred to. This tube has the corrugations 44. Between the corrugations is a. helically wound strip of metal having a cross section comprlsing the radially extending fin 45 and foot 46 at right angles thereto. The strip last referred to is wound helically within the groove of the tube 43 between the corrugations 44, and the foot 46 rests upon the tube 43 between the corrugations. The strip comprising the fin 45 and foot 46 may be secured 130 the tube 43 by soldering, welding or in other suitable ways, or it may be unsecured. to the tube 43 merely resting against it.

It will be seen that the fin 45 of the strip couducts the heat of the pocketed air between the corrugations outwardly and dissipates it; also, the strip, including the fin 45 and the foot 46, being in contact with the tube 43, will act to directly eonduct the heat from the tube outwardly, which further fact improves the radiation because heated air being pocketed between the corrugations, the tube between the corrugations does not so readily radiateits heat.

In Fig. 3 is'shown a modified construction 01 tube havlng a radiating fin between its corrugations, the corrugated tube being shown, like that in Fig. 2, as being the same as shown in the Brinkman patent hereinbefore referred to. The fin 48, however, instead of being formed of a helical strip 015 angular cross section, is formed 01 a flat strip helically wol'md in the groove between the corrugations of the tube 41. The fin or strip 48 facilitates the dissipation of heat from between the corrugations as already explained in connection with the device of Fig. 2 and may be soldered, welded, or otherwlse secured to the tube or may simply lie upon lt as it is wound thereon.

In Fig. 4 is shown, partly in side elevation and partly in section, a corrugated tube whlch is integrally formed instead of being formed of a strip as hereinbefore referred to. This integrally formed corrugated tube has a fin 64 located between the corrugations 65. This fin is formed of a helical strip of metal or other suitable beatconducting material. This strip may be welded, brazed, soldered or otherwise suitably secured to the tube, or itmay simply lie in contact therewith.

In Fig. 5 is shown an integrally formed corrugated tube having a helical strip of metal or other suitable heat-conducting material secured to the outer side of the corrugation by soldering, brazing, welding or in any other suitable way, this strip forming a hea.t radiating fln in couiunction with the corrugation.

Whlle the invention has been illustrated in what are considered its best applications, it may have other embodiments without departing from its splrit and is not therefore limited to the structures shown in the drawing.

What we claim is:

1. The combination with a helically corrugated tube, of a separate strip helically disposed about said tube and secured thereto at its inner edge,

said strip being between the Corrugations of said tube and comprising flat portions of different cross sectional dimensions at right angles to each other, the greater of said dimensions extending radially of the axis of the tube.

3. The combination with a corrugated tube, of a separate strip helically disposed with relatlon to the axis of said tube and secured thereto. said strip being mounted ab the unter end of the corrugation.

4. The combination with a tube formed of a helically disposed strip having the edges of adjacent convolutions secured together in a fixed jolnt and a heat-conducting fin secured in said jolnt and extending outwardly therefrom.

5. The combination with a corrugated tube comprislng a helically disposed strip having a longitudinally extending groove forming a sorrugation in the completed tube, the edges of adjacent convolutions being secured together in a fixed joint, of a helically disposed heat-conducting fin entering in said joint and projecting outwardly, said joint being at the outer surface of the corrugation.

6. The combination with a corrugated tube, 015 a helically disposed strip having an angled section, one of the legs 0f said section being secured. to said tube and the other leg projectin'g outwardly.

7. The combination with a corrugatecl tube comprlslng a. helically'disposed strip having a longitudinal groove forming a corrugation in the completed tube, and the edges of adjacent Convolutlons of the strip being interfolde'd to form a joint between the convolutions, of a helically disposed strip having a right-angled section, one of the legs of the angle being inserted in said joint and the other leg of said angle projecting outwardly.

8. The combination with a corrugated tube comprising a helically disposed strip having a longitudinal groove forming a corrugation in the completed tube, and the edges, of adjacent Convolutions of the strip being interfolded to form a joint between the convolutions, of a helically disposed. strip havinga right-angled section, one cf the legs of the angle being inserted in said joint and the other leg of said angle projecting outwardly said joint being at the outer end of the corrugation.

EDWIN F. TILLEY. R. HARRY STONE.

Images