US2587700A

US2587700A - Fuel burner

Info

Publication number: US2587700A
Application number: US744083A
Authority: US
Inventors: Cowan Harry
Original assignee: Babcock and Wilcox Co
Current assignee: Babcock and Wilcox Co
Priority date: 1947-04-26
Filing date: 1947-04-26
Publication date: 1952-03-04
Anticipated expiration: 1969-03-04

Description

March 4, 1952 H. cowAN 2,587,700

FUEL BURNER Filed April 26, 1947 2 SHEETS-SHEET 1 INVENTOR flarrg Con an BY Mann- ATTORNEY H. COWAN FUEL BURNER March 4, 1952 2 SHEETSSHEET 2 Filed April 26, 1947 Fig. 3

INVENTOR flar/g' Cowan BY ATTORNEY Patented Mar. 4, 1952 UNITED STATES PATENT OFFICE FUEL BURNER Application April 26,1947, Serial No. 744,083

7 Claims- 1 This invention relates general to the contruetion nd operatio o li u d .f el burners and more particularl to the. c nst uc ion a d operation o the su p y co n c ns or qu d uel burners o the flu d om ins type,

Liquid fuel burners are normally mounted in a position in a furnace wall where at least their discharge ends are subject to the high furnace temperatures. I operation, the ow of liquid fuel t rou h the burner end to m nt n t urner metal at a sa e pe ating t mper ur but when the liquid fuel supp y s ff, s when installin or chan ing urn r th b rner metal is liable to be overheated if exposed for even a elativ y short t m to high tempe atu es before t s Withdrawn or he fuel supp y res ored. There is also normally a l qu d fu re d le t in the fu l passa e. when the u supp y is out off, and th s res due t nds o ch r or coke, a d thus whol y or p rt y clo th f el pas ge, r quiring the burner to be dismantled for cleaning. Coking is particularly liable to occur when the liquid fuel is of a relatively viscous type, such as bunker fuel oil, tar, or pulp residual liquid. When such fuels are to be introduced into the furnace in a finely atomized condition, the atomiZation is usually effected by an atomizing fluid, Such as steam, or in some cases air, at a pressur igher han t at of the q d fuel d 110 ing through the burner in a stream surrounding or With n th burn r uel passage to a point wh r the a mizing .fiuid mping s on he l q id fuel s ream to a om ze the same- In accordance with the present invention, the

atomizing fluid and liquid fuel supply connect tions of a liquid fuel burner of the fluid atomizing type are constructed and arranged to automatically provide a flow of atomizing fluid through the liquid fuel passage of the burner whenever the liquid fuel supply to the burner is cut off, to not only cool the burner metal but also simultaneously purge the liquid fuel passages of the burner and supply connection of any fuel residue therein.

In the drawings:

F 1 is an elevation p rtly in sect on of a iquid fuel burner a sembly mounted a urn ce wall;

Fig. '2 is a front view of the burn supply C 1- nee ohs;

Fig. 3 is a detai o the burn r dis harge end; and

Figs- $1.5 and 6 are par ly'diagrammati views showing different operating positions of the con.- trol mecha ism.

In the drawings, the invention is illustrated as embodied in the supply connections of a liquid fuel burner In of the fluid atomizing type rem ab y ounted in a clamp of a burner mounting 12 positioned in an opening in a verti, cal wall I3 of a water cooled furnace. As shown in Fig. 3, the fuel burner I0 is of the type disclosed in the copending application of James Fletcher, Serial No. 744,891, filed April 30, 1947, and includes a central pipe l5 surrou ded by a spaced pipe [6, thus forming an inner fuel passage surrounded by an annular steam passage. The fuel pipe [5 opens into a transversely elone gated slot of a sprayer plate I! into which a series of steam passages l8 open at points intermediate the lot length. With this on truction. the liquid fuel stream is impinged on by a multi,- plicity of steam jets at a higher pressure, atomizing the liquid fuel into a finely divided condition. A coupling containing steam and liquid fuel inlets 2| and 2-2 is detachably connected to the burner steam and fuel passages respectively. The steam inlet 2| is connected through a nipple 23, union 24, and elbow to an upwardly curving 7 flexible steam hose 26. The fuel inlet 22 is sin ilarly connected. through a nipple 21, union 28, and elbow 29 to an upwardly curving flexible fuel hose 30.

The steam hose 26 is connected throu h a coupling to a discharge opening of a three-way thr e-pert ro ry p ug valv 34. The in et op ning of the valve 34 is connected by a pipe 35 to a subjacent steam supply header 36. The fuel hose 30 is connected to a discharge opening of a three-way two-port rotary plug valve 40, the in.- let opening of which is connected through a pipe 4! to a subjacent liquid-fuel supply header 42. The arrangement of the valves 34 and at the high point of the burner assembly facilitates drainage away from the valves to the associated conduits, The rotary plugs or cocks of the valves 34 and All are simultaneously rotated by a common yoke detachably connected thereto and having an operating lever 46. In accordance with the invention, the valves are connected by a sectional by-pass pipe 49 to permit a controlled flow of steam from the valve 34 through the pipe 49 and valve 40 to the liquid fuel hose 30. With the pipe connections illustrated, the steam and liquid fuel supply sections of the burner assembly can be separately dismantled.

In Figs. 4, 5 and 6, the arrangement of the ports of the valves and 40 are indicated for different positions of the operating lever 48. Fig. 4 shows the lever in a vertical up bositlon 3 when the burner is off, the valve ports being then arranged so that the flow of both steam and liquid fuel is cut off. As the lever is moved downwardly 90 to a horizontal position, the

valves

34 and 40 are rotated so that steam will flow through the valve 34 not only to the steam hose 26 but also through the bypass pipe 49 through the valve 40 to the liquid fuel hose 30, the fuel supply being cut off. In this position the fuel burner will have a flow of steam through both the inner fuel pipe l5 and the surrounding steam pipe l6. As shown in Fig. 6, as the handle is turned 90 to a vertical down position for the burner on position, the

valves

34 and 40 are rotated so that the valve 34 cuts off the supply of steam to the by-pass pipe 49 and delivers steam only to thesteam hose 26, while the valve 40- is rotated to close off the by-pass pipe and deliver liquid fuel from the fuel header 42 to the fuel hose 30. .Thelever movement is reversed when moving from the burner on position to the burner off position.

When for example, the fuel burner is to be installed in the mount 12, it is first positioned in the clamp II with its discharge end backed well out of the furnace. Before it is slipped down into its operating position, the lever 46 is turned to its horizontal or purging position so that steam will flow through both the steam and fuel passages of the burner. The burner is then slipped down in the clamp into its operating position and the valves turned to the burner on position shutting off the steam flow through the by-pass connection and opening the liquid fuel supply to the burner. In withdrawing the burner after use, the valve operating procedure is reversed, the valve lever being first turned to the purging position and the burner pulled back out of the furnace but not out of the clamp II. The lever is then turned to the burner off position and the burner unclamped and removed from the burner mount.

The burner assembly described provides a relatively simple and low cost construction for insuring adequate protection of the burner from overheating and clean liquid fuel passages in the burner assembly whenever the burner is put into operation.

While in accordance with the provisions of the statutes I have illustrated and described herein the best form of the invention known to me, those skilled in the art will understand that changes may be made Without departing from the spirit of the invention covered by my claims, and that certain features of my invention may sometimes be used to advantage without a .corresponding use of other features.

I claim:

1. A liquid fuel burner assembly comprising a liquid fuelburner having a liquid fuel discharge passage and an atomizing fluid discharge passage therein, a liquid fuel supply conduit and an atomizing fluid supply conduit connected to said passages respectively, a three-way rotary valve in each of said conduits, an atomizing fluid by-pass passage independent of said conduits and directly connecting said valves, and means for simultaneously rotating said valves into successive operating positions, in one of which said valves are positioned to direct atomizing fluid from said atomizing fluid supply conduit through said by-pass passage to said burner liquid fuel discharge passage.

2. A liquid fuel burner assembly comprising a liquid fuel burner having a liquid fuel discharge passage and a steam discharge passage therein, a liquid fuel supply conduit and a steam supply conduit connected to said passages respectively, a three-way three-port valve in saidsteam supply conduit, a three-way two-port valve in said liquid, fuel supply conduit, a steam-by-pass passage independent of said conduits and directly connecting said valves, and means for moving said valves into successive operating positions including an intermediate position in which said valves are positioned to direct steam from said steam supply conduit through said by-pass passage and liquid fuel supply conduit valve to said burner liquid fuel discharge passage.

3. A liquid fuel burner assembly comprising a liquid fuel burner having a liquid fuel discharge passage and steam discharge passage therein, a liquid fuel supply conduit and a steam supply conduit connected to said passages respectively,

a three-way three-port rotary plug valve in said steam supply conduit, a three way two-port rotary plug valve in said liquid fuel supply conduit, conduit means separate from said supply conduits forming a steam by-pass passage directly connecting said valves and providing continuously open communication therebetween, and common operative means for simultaneously rotating said valves into successive operating positions including an intermediate position in which said valves are positioned to direct steam from said steam supply conduit through said bypass passage and liquid fuel supply conduit valve to said burner liquid fuel discharge passage, said valves in another of said positions cutting off the supply of liquid fuel and of steam to the respective burner discharge passages.

4. A liquid fuel burner assembly comprising a liquid fuel burner having a liquid fuel discharge passage and a steam discharge passage therein, a liquid fuel supply conduit and a steam supply conduit connected to said passages respectively, a three-way three-port rotary plug valve in said steam supply conduit, a three-way two-port rotary plug valve in said liquid fuel supply conduit, conduit means separate from said supply conduits forming a steam by-pass passage directly connecting said valves and providing continu-' ously open communication therebetween, and common operating means for simultaneously rotating said valves into successive operating positions including an intermediate position in which said valves are positioned to direct steam from said steam supply conduit through the valve therein to both said burner steam discharge passage and said by-pass passage, and through said by-pass passage and said liquid fuel supply conduit valve to said burner liquid fuel discharge passage, said valves in other positions respectively opening up and cutting off the supplies of liquid fuel and steam to the respective burner discharge passages.

5. In combination with, a liquid fuel burner having a liquid fuel discharge passage and an atomizing fluid discharge passage therein, a valved conduit structure comprising a pair of headers constituting a liquid fuel supply header and an atomizing fluid supply header respectively, a liquid fuel supply conduit and an atomizing fluid supply conduit connecting the respective headers of said pair to said passages respectively, a valve in each of said conduits, an atomizing fluid by-pass conduit directlyv connecting said valves and independently of said supply conduits providing continuously open communication therebetween, and valve operating means for moving said valves simultaneously into different operating positions, in two of which positions said valves are positioned to shut oiT, and to open up, respectively, the supply of liquid fuel and atomizing fluid to said burner discharge passages respectively, and in a position intermediate said two positions said valve in said atomizing fluid supply conduit is positioned to direct atomizing fluid from said atomizing fluid supply conduit in part to said burner atomizing fluid discharge passage and in part to said atomizing fluid bypass passage, while said valve in said liquid fuel supply conduit is positioned to shut off the supply of liquid fuel to said burner liquid fuel discharge passage and to direct atomizing fluid from said by-pass passage thereto.

6. In combination with a liquid fuel burner adapted to be adjustably positioned relative to a firing zone and having a liquid fuel discharge passage and an atomizing fluid discharge passage therein, a valved conduit structure comprising a pair of horizontally disposed stationary headers constituting a liquid fuel supply header and an atomizing fluid supply header, a liquid fuel supply conduit and an atomizing fluid supply conduit ating positions, said supply conduits having flexible outlet end portions intermediate said valves and said burner discharge passages.

7. A liquid fuel burner assembly comprisin a liquid fuel burner having a liquid fuel discharge passage and an atomizing fluid discharge passage therein, a liquid fuel supply conduit and an atomizing fluid supply conduit connected to said passages respectively, a three way valve in each of said conduits, an atomizing fluid by-pass passage independent of said conduits and directly connecting said valves, and valve operating means for moving said valves simultaneously into different operating positions, in two of which positions said valves are positioned to shut ofi, and to open up, respectively, the supply of liquid fuel and atomizing fluid to said burner discharge passages respectively, and in a position intermediate said two positions said valve in said atomizing fluid supply conduit is positioned to direct atomizing fluid from said atomizing fluid supply conduit in part to said burner atomizing fluid discharge passage and in part to said atomizing fluid lay-pass passage, while said valve in said liquid fuel supply conduit is positioned to shut off the supply of liquid fuel to said burner liquid fuel discharge passage and to direct atomizing fluid from said by-pass passage thereto.

HARRY COWAN.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 470,711 Siemens Mar. 15, 1892 1,221,288 Canaday Apr. 3, 1917 2,013,302 Furguson Sept. 3. 1935