US1772046A - Gas-fired boiler - Google Patents

Description

Aug. 5, 1930. G. H. IRWIN GAS FIRED oILER Filed oct. 17, 1927 2 Sheets-Sheet l I l \l/// 7 3 w g M 6 0 J I@ w f 77 M :H HMMHHIAUWI NMI-- l 1 .H w. 2 J A- H Q0 l-- m n 3 N WJ f v 5 g /f www N M G Q n 2 f L X Fwd L #v fd x 3n L l L w Alll o\ 1 y n L u r|| L w 1 62/ M u L d u MW. Aa m Illv 7 oO 6 (f. J w

Aug. 5, 1930.4 G. H. IRWIN GAS FIRED BOILER Fi1 ed Oef. 17; 1927 2 Sheets-Sheet 2 Patented Aug. 5, 1930 GFDRGE H. IRWIN, F CHICAGO, ELINOIS y GAS-FIRES!) BOILER Application ned october 17, 1927'. serial m. 226,568.

My invention relates to gas fired boilers artlcularly adaptable for steam vor hot water eating systems or for heating water for industrial or household use.

An important object of the invention is to provide construction and arrangement for causing the water and the burning gas or heat to iiow in counter currents or streams, 'and to segregate the hot and cold zones of water and gases so that the heat convection'is uniform and perfect and to cause the expansion and contraction of the boiler sheets and tubes to be uniform. A

Another important object is to provide an economizer boiler section concentric with and surrounding the main .boiler section, into which economizer section the cold water is fed and flows upwardly around fire tubes through which the combustion gases iow downwardly to the smoke box to exit through the stack, the water thus drawing the heat from such gases for preliminary heating be.-

fore entering the main boiler section, the

economizer section also formin an insulatin jacket around the main bo' er section to re uce heat lossto a minimum.

Anotherimportant object is to provide baille means for causing the preheated water from the economizer section to flow downwardly in the lower' part of the main boiler section and around the fire tubes to the bottom tube sheet before flowing upwardl to the steaming space at the upper part o the boiler.

Another important object is to burn the gas en masse in a lire box closed to the atmosphere and to produce a uniform and eliicient m'ix ture of gas and airfor perfect flame and combustion conditions irrespective of weath- 40 er or draft conditions; to thus eliminate the 'evils of multiple separable, adjustable, as burner units and atmospheric burning. y means 'ofa blower I thoroughly mix gas and air in proper proportion and ositively feed the combustion mixture into t e fire box below the fire tubes.

Another object is to dispense with pilot burners and to provide improved and more reliable means or igniting the combustion somixtureasitleavestlmhlowel-,suchmeans being preferably in the form of a spark plug which may be readily controlled to function as soon as the blower is started and to insure ignition of the combustion mixture.

The above and other features of my invention are incorporated in the structure shown on the drawings, in which Fig. 1 is a vertical diametral section of the boiler structure. y

Fig. 2 is a section on plane 2-'2 Fig. 1, and 60 Fig. 3 is a section on plane 3-3 Fig. 1. The boiler structure comprises the outer cylindrical shell 1 from whose upper end exl tends the annular tube plate 2, and an inner cylindrical shell 3 concentric with but of less 65 diameter than the outer shell. Across the upper and lower ends of the shell 3 extend the upper and lower tube 1sheets 4 and 5 respec tively in which are seated the fire tubes 6, these parts forming the main boiler section. An angle bar ring 7 is secured around' the lower end of the shell 3 and rests on the cylindrical base 8 which has the bottom 9, the base sides and bottom being lined with heat refractory material 10. The outer shell 1 75 rests on the ring 7 and a band 11 assists in holding the -shell in'position.

Between the shells 1 and 3 and a distance above the bottom tube sheet 5 is the annular tube sheet 12 which extends between the shell 80 Y 1 and the lowe'r end of the intermediate shell 13 which is concentric with but spaced from shell 3 to leave the annular space or passage 14. The annular top plate 2 extends between the upper end of the shell 13 and the outer 95 shell 1. The shells 1 and 13 and the tube plates 2 and 12 enclose the annular space 15 through which extend the lire tubes 16. The shells 1 and 3 together with the tube sheet 12 and the ring 7 enclose the annular smoke 90 space 17 which communicates with the lower ends of the tubes 16 and assage 14 and which at one side-is connecte with the 'stack At one side of the boiler structure the water inlet pipe 19 extends through the shell 1 to feed water into the space 15 at the lower end thereof, and at the opposite side of the boilerstru'ctureapipeil()extendsthroughthef shellltooonnectwiththetopofthespx 1" 15, the pipe at its lower end extending through the shells 1 and 3 to connect w1th the water space of the main boiler section a distance above the bottom tube sheet 5 as indicated at 20.

Extendingdownwardlyfromtheuppertube sheet 4 to a. point below the pipe end 20 and above the bottom tube sheet 5 is the cylindrica] baffle shell 21. This shell is concentric with but of less diameter than the shell 3 to leave the intermediate boiler section 22 between these shells, and through this section extend the 'fire tubes 23 which seat at their ends in the upper and lower tube sheets 4 and 5.

Extending laterally from the upper end of the baille' shell 21 to the exterior of the lboiler is the steam header 24 which conducts the heated steam to vthe heating system .radiators. The baffle shell has also the passage opening 25 at its upper end for the flow through the shell and to the steam header of steam generated in the space 22 by the lheat from the tubes 23. A water column structure 26' is connected by pipe 27 with the in terior of the boiler to indicate the boiler water level.

On top of the boiler is the cap 28, preferably of sheet metal, which forms the chamber 29 with which the various fire tubes communicate at their upper ends. Preferably an inner wall 30 is provided to form insulating space 31 which may be filled with heat insulating material.

Within the base 8 is the fire or combustion chamber 32 and through the base wall is the opening 33 into which projects the outlet nozzle 34 of a centrifugal blower 35 driven by an electric motor 36. Through piping 37 gas and air are drawn into the blower in proper proportion and thoroughly mixed before delivery into the combustion chamber.

'To ignite the combustion mixture I preferably use electric sparks and one or. more spark plugs 38 are applied to the blower nozzle to project sparks into the outflowing combustion mixture to ignite the same. Suitable and well' known electrical apparatus may be utilized to produce the sparking. As diagrammatically shown a cam or contact wheel 39 cooperates with a contact 40 to make and break the electrical circuit 41 fed by a current source 42. One terminal of the source connects with the contact wheel and the other terminal with the blower frame, while the contact 40 connects with one terminal of the spark plug whose other terminal connects wlth the blower frame. The .contact wheel may be connected to be rotated by the motor so that whenever the motor operates the blower to deliver combustion mixture the spark p lug will operate to ignite the mixture. Operation of the motor may be controlled from a dlstance by means of a switch 43 in the motor supply circuit.

Describing now the operation, the feed or Vreturn water enters at the bottom' of the space 15 through the pipe 19 and flows upwardly through the space to be preheated by the gases flowing downwardly through the tubes 16 and the annular passage 14 on their way toI the smoke chamber 17. The preheated water flows downwardly through pipe 20 into the space 22, and being cooler than the water at the bottom of themain boiler section, it iiows downwardly toward the hot tube sheet 5 to mix with the hot water and be further heated before flowing around the lower end of the baiile shell 21 and upwardly through the shell around the fire tubes 6. The water also rises in the space 22 to be heated by the fire tubes 23, the water level be ing at a. distance below the top tube sheet to leave space for the heated steam, the steam flowing out through the header 24 for distribution. The steam generated in the space 22`finds its way through the passage 25 into the baiiie shell and from there to the header 24.

` The space 15 forms the economizer section of the boiler as the water is given a preliminary heating by the outlowing gases before it enters the hot zone of the main boiler section. lln this economizer section Vthe water flows counter to the gas flow through the tubes 16 and passage 14 and extracts any available heat left in the gases before they reach the stack. When the preheated water enters the main boiler section it again flows counter to the flame in the re tubes. This arrangement segregates the hot and cold zones of water and gases so that the heatconveetion is uniform and perfect and the expanslon and contraction of the tubes andsheets are uniform. The economizer section acts also as an/insulating jacket to reduce heat loss to a minimum.

It will be noted that the combustion cham- A ber 32 is closed to the atmosphere, the combustion gas receiving itsproper air supply thoroughly intermixed therewith in the l ing down and disturbing the molecular structure of the gas with the admission of the correct quantity of air, and the delivery of the combustion mixture into the combustion chamber under pressure sand speed. The feed is thus positive and independent of any atmosphere or gas condition and is'not affected in any way by back draft. l

The electrical ignition of the combustion by the spark' plug eliminates troublesome pilot flames which may be readily extinguished by back draft. With `my arrangement, the ignition operates only when the blower is operating and combustion mixture is being delivered.;l

The boiler structure is of simple and comparatively inexpensive construction. Practically all the parts can be cut from standard stock material of any suitable metal. The structure is self contained and can be completely assembled and tested in the shop prior to shipment. Installation cost is therefore materially reduced. Being practically entirely of sheet metal it is also comparatively light A and easily shipped, handled and installed.

I do not desire to be limited to the exact structure and arrangement shown as changes and modifications are possible which would come within the scope of my invention.'

I claim 1. In a vertical lire tube boiler, the combination of a main boiler section having updraft fire tubes, an economizer boiler section surrounding the main boiler section and having down-draft ire tubes, an intermediate boiler section having up-draft re tubes, said economizer section-having a water inlet at its lower end and a water outlet at its upper end whereby the water tlowstherein counter current to the draft, said outlet connecting with said intermediate section a distance above the lower end thereof, a connection between said intermediate and main sections, means for causing the water to flow downwardly in said intermediate and main sections counter current to the draft before flowing upwardly through said main section, and a steam delivery outlet from the upper part of said main section.

2. In a vertical fire tube boiler, the combination of a main boiler section having up draft fire tubes, 4an economizer boiler section surrounding the main boiler section and having down-draft lire tubes, an annular downdraft tire passage between said sections, a combustion chamber below said main boiler section, a cap above the main and economizer sections, a smoke box below the down-draft -ire tubes and a stack'extending therefrom,

and means for causing the water to flow counter current tothe draft in said economizer sectionand counter current to the draft at the lower part of themain boiler section.

v 3. In a vertical firel tube boiler, the combination of a main boiler section, having updraft fire tubes, an economizer boiler section surrounding the' main boiler section and having down-draft re tubes connected at their upper ends with the upper ends of the mainsection tubes, a fire box below said vmain section tubes, a smokebox below said economizer section and a stack extending therefrom, said economizer section having a water inlet at its lower end and a water outletat its upper end whereby water will flow in said sectlon counter current to the draft, said outlet connecting with said main section a distance above the lower end thereof, a baie for caus- -ing the water from the economizer section to ow downwardly to the bottom of said main section before flowing upwardly in said main section, said boiler sections being disconnected from each other at their .upper ends, and a -tu es, an intermediate boiler section having 11p-draft `tubes and separated from the outer i section by a down-draft passage, a hood receiving the upper ends of all said tubes, a furnace below the main and intermediate sections, a smoke box below the outer section and surrounding the main and intermediate sections, a stack extending from said smoke box, said outer section having a water inlet at its lower end and a water outlet at 'its upper end, said outlet being connected with said intermediate section a distance above the bottom thereof and said intermediate section being connected with the main section at the bottom thereof, a steam delivery pipe extending from the upper part of said main section, and a. steam passage between the main and intermediate sections above the boiler water level.

5. In a vertical fire tube boiler, the combination of a main boiler4 section, an economizer boiler section surrounding said main section, an intermediate boiler section between said main and economizer sections, said Y sections being connected in'series for the flow of water, a water inlet for the economizer section, means causing the water to flow through the sections counter current to the direction of'the draft through the tubes in the sections, a delivery pipe for steam extending from the main section, and a passage from the steam space of the intermediate4 section tothe steam space of the main section for the flow of steam from the intermediate section into and through the main section before reaching the delivery pipe.

' 6. In a vertical fire tube boiler, the combination of a main boiler section having up draft fire tubes, an economizer boiler section surrounding said main section and having down draft tire tubes, and an annular down draft fire passage between said sections, said economizer section having a water inlet at its lower end and a water outlet at its upper end connected with the main boiler section below the water level therein. l

l 7. In a' vertical fire tube boiler, the combination of a main boiler section having up draft tubes, an economizer boiler section having down draft tubes, an intermediate boiler nu A let from the top of said main section, and a steam passage between said main and intermediate sections above the water level there- 8. In a vertical lire tube boiler, the combination of a main boiler section comprising upper and lower tube sheets and lire tubes extending between said sheets, a baille shel'l eX- tending downwardly lfrom said top sheet to within a short distance of the lower sheet to divide said main boiler section into inner and outer boiler parts, an economizer boiler section surrounding the main boiler section and separated therefrom by an annular lire passage, I'ire tubes in said economizer section, a furnace below the main boiler section, a smoke cap above said main boiler section and said ec'onomizer section receiving the gases from said main boiler section tubes, a smoke box surrounding said main boiler section below said economizer section to receive the gas from said economizer section tubes and from said iire passage, a stack leading from said smoke boX, a water inlet at the lower end of said economizer section and an outlet therefrom connected with said inner boiler part a distance above the lower end of said baille shell, a steam supply outlet from the top of said inner boiler part, and a connection for the flow of steam from said outer boiler` part to the'steam space of said inner boiler part.

9. In a vertical lire tube boiler, the' combination of a shell having upper and lower tube sheets connected by lire tubes, a baille shell extending downwardly from said upper sheet to within a short distance of said lower sheet to form inner and outer boiler sections, a water inlet to said outer section a distance above the lower end of said balile shell but below the boiler water level whereby water must flow downwardly before iowing upwardly in the inner boiler section, an outlet forsteam from one side of said inner boiler section, and a steam passage between the opposite side of said inner boiler section andv said outer boiler section whereby the steam .from said outer section must flow across the nner section before reaching said steam out- 1Q. In a vertical fire tube boiler, the combination of a main boiler section having updraft re tubes, an economizer boiler section surrounding the main boiler sectionand having downclraft re tubes, an annular downdraft fire passage between said sections, a combustion chamber below said main boiler section, a cap above the main and economizer sections, a smoke. box below the downdraft fire tubes and fire assage and a stack extending from said smo e box.

11. In a vertical re tube boiler, the combinat-ion of a main boiler section having ire tubes, an economizer boilersection surrounding sald main boiler section and having fire tubes, a contlnuous annular re passage sepa.-

GEORGE I-I. IRWIN.

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