US3072344A

US3072344A - Unitary y-jet spray head assembly

Info

Publication number: US3072344A
Application number: US76867A
Authority: US
Inventors: Edwin C Mckenzie
Original assignee: Babcock and Wilcox Ltd
Current assignee: Babcock International Ltd
Priority date: 1960-12-19
Filing date: 1960-12-19
Publication date: 1963-01-08
Anticipated expiration: 1980-01-08

Description

Jan. 8, 1963 E. c. McKENzlE UNITARY Y-JET SPRAY HEAD ASSEMBLY Filed Dec. 19, 1960 JNVENTOR.

Edwin Charles Mc Kenze .Ww will?? ATTORNEY Patented "Jan. 8, 1963 3,072,344 UNITARY YJET SPRAY HEAD ASSEMBLY Edwin C. McKenzie, London, England, assignor to Bahcock & Wilcox, Limited, London, England, a corporation of Great Britain Filed Dec. 19, 1960, Ser. No. 76,867 Claims. (Cl. 239-425) This invention relates to a liquid lfuel burner, and more specifically to a liquid atomizing fuel burner and improved atomizin g head therefor.

In British Patent No. 579,591 which corresponds to United States Patent No. 2,414,459, the atomizer head ofthe type of liquid fuel burner therein disclosed is cornposed of several separate and distinct elements, each being serially disposed in abutting relationship with the terminating plate or nozzle piece thereof being seated at the bottom of an annular recess formed in the end of the outer burner conduit.

In a liquid fuel burner of the type in question, an elastic fluid such as steam is often employed to enhance atomizing. In practice it has been noted that a leakage of steam is likely to occur at the abutting joints Vformed between the several separable parts of the atomizing head resulting in a very substantial increase in the cost of fuel and makeup water. Moreover, unless the seating of the terminal plate or nozzle piece at the bottom of the annular recess, formed in the end of the outer conduit, is maintained clean, and the terminal plate tightly clamped in position, seepage of oil may occur thereat. Such loss or leakage of oil is likely to result in imperfect combustion conditions and damaged components, such as the impeller plate and/ or some other burner part.

An object of this invention is to provide for improved burner operation and efficiency by utilizing a novel unitary or integrally formed atomizer head for effecting the mixing of two fluids, arranged and constructed to communicate with the respective supply passageways of each of the two iluids in a manner so as to minimize leakage therebetween.

Another object is to provide for an improved joint connection between an atomizing head and its adjoining fluid or fuel supply conduit.

Still another object of the invention is to provide a pressurized seal or packing between the burner supply conduits and lthe burner housing.

The foregoing objects, and other features and advantages in accordance with this invention are attained by an atomizing head of unitary construction having. inlet ducts for both liquid fuel and an elastic fuel in direct communication with the respectivel conduits supplying the fuel and elastic uid thereto. Generally the unitary atomizing head consists of a body having a laterally extending ange intermediate the ends thereof having a threaded coupling boss integrally connected on one side of the flange, and a lfrusto-conical face boss defining the sprayer face connected to the other side of the ange. Accordingly, the rear surface of the 'flange is inclined to deline a frusto-conical surface which is adapted to seat against a complementary bevel formed in the end of a supply conduit when assembled thereto.

The various features of novelty which characterize my invention are pointed out with particularity in the claims annexed to and forming a part of this specification. For a better understanding of the invention, its operating advantages and specific objects attained by its use, reference should be had to the accompanying draw- FIG. 1 is a fragmentary sectional side view of the burner assembly in accordance with this invention.

FIG. 2 is an end section of the burner as seen from the left hand end of FIG. 1.

FIG. 3 is a sectional view taken along line 3 3 of FIG. 1.

The burner as illustrated in FIG. 1 is adapted to be arranged in a furnace port in a manner described and illustrated in the specification of the British Patent 579,- 591 which corresponds to the United States Patent 2,414,459. Accordingly, fuel oil and steam are supplied to the burner at similar pressures to those disclosed in the above patented disclosures, and the capacity of the burner is varied in a similar manner by regulation of the oil and steam supply pressures.

Referring to FIG. 1, the burner assembly comprises a body 1 which includes an open end sleeve or tubular housing 7. A ilanged coupler 2 having threaded bosses 3 and 4, co-axially disposed on opposite sides of the flange, is threaded to one end of the housing. The other end of the flange coupler 2 is threaded into a tting 8 which connects with the end tting of a suitable steam line. Boss 3 of coupler 2 is internally threaded for receiving the threaded end of an inner burner tube or conduit 6 concentrically disposed in spaced relation-ship with respect to the sleeve housing 7. As shown the end of conduit 6 abuts against a shoulder in boss 3` to form a uid tight joint therebetween.

As shown in FIG. l the bore of sleeve 7 is progres-y sively sized by a plurality of longitudinally spaced stepped portions defined by shoulders 9, 13, and 12, the latter twol shoulders being beveled. The diametrically larger portion 11 and the smallest portion 43 of the bore are internally threaded. Extending radially of sleeve 7 is an opening into which there is brazed an internally threaded pipe stub 14 to which a suitable fuel line (not shown) is attached. The pipe stub 14 opens into an annular chamber 15 formed within the sleeve 7.

An outer tube or conduit r16`is concentrically disposed in spaced relationship with respect to the inner conduit 6 to dene there between an annular passageway 2). As shown, the inner end 17 of the outer conduit 16 is spaced from the end of the threaded boss 3 to define a boundary of the fuel chamber 15, and an annular inlet to passageway 20. An annular groove 1S circles the end portion 17 of the outer conduit 16 and a circlip 19 disposed within the groove 18 is loosely fitted within the bore of the sleeve adjacent chamber 15.

The gap formed between the outer conduit 16 and the sleeve 7, as shown in FIG. 1, is closed in accordance with this invention by an annular gland 21, which is held in position by an insert portion of a hexagonally headed clamp nut or collar 22 screwed into the end 11 of the sleeve 7. Gland 21 comprises a pair of spaced brass collars or sealing

members

52 and 23. As shown, the opposed laterally extended surfaces of the

respective sealing members

52 and 23 are provided with a complementary V-shaped surface. Disposed between members 53, 23, are a plurality of separate and distinct chevron sectioned packing rings 24. The packing rings preferably are made of impregnated asbestos, and each is provided with a central or annular groove 27 from lwhich a series of holes 28 extend through the thickness of the packing ring. Thus it will be noted that the distribution holes 28 serially connect the groove 27 of one ring 24 with the groove 27 of the next adjacent packing ring.

As shown in FIG. 1, sealing collar or ring 52 is also provided with an annular groove 26 which is in communication with gap formed between the outer conduit 16 and the bore of the sleeve 7. A plurality of circumferentially spaced distribution holes 25 connect the angular groove 26 of collar 52 into communication with angular groove 27 of the next adjacent packing ring 24. Consequently it will be noted that the oil pressure from chamber is transmitted about the loosely fitted circlip 19 past shoulder 13, into circular groove 26, through holes and to each of the packing rings 24 by way of the serially connected groove and

holes

27 and 28 of the respective packing rings 24. Thus the gland or seal 21 is subjected to the pressure of the fuel in chamber 15, and in this manner the sealing effect of the gland 21 is enhanced.

The inner and outer conduits 6 and 16 respectively extend to the atomizing head 10 of the burner to convey the steam and fuel oil thereto. As shown the external end portions 31 and 32 of the conduits 6 and 16, respectively, are reduced and externally threaded.

In accordance with this invention, a unitary atomizing head is detachably secured to the ends of conduits. As shown, the atomizing head 1t) is formed of a one piece construction which consists of a body having a laterally extending ilange 29 disposed intermediate the ends of the body. An internally threaded coupling boss 35 is connected on one side of flange 29 by which the head 10 is detachably screwed onto the threaded end 31 of the inner conduit 6. The atomizing head 10 is also clamped onto the end of the outer conduit 16 by an apertured cap nut 36 which screws onto the end portion 32 of the outer conduit 16.

In accordance with this invention a self centering frustoconical joint is formed between surface 34 of flange 29 of the atomizing head and the beveled outer end of tube 16 for insuring a good seal therebetween. The end face of the inner tube or conduit 6 is arranged to abut an angular shoulder 53 in the atomizing head 10 so that steam from the inner conduit 6 is prevented from escaping between the threaded boss and tube 6.

As shown in the drawing a frusto-conical face boss 37 is integrally connected to the other side of flange 29 of head 10 in co-axial relationship with coupler 35.

In the coupler boss 35 there is extended a central well 50 which projects into the interior of the flange portion 29 of the head 1t), the well bottom 51 being conical in shape. A bevel surface 40 is formed around the edge of the well communicating with the bore of conduit 6 so that the maximum diameter of the well 50 is substantially equal to that of the passageway of conduit 6.

The face portion of boss 37 is projected through the fapertured` cap nut 36 and is provided in the plane of its conical face a ring of fuel discharge orifices 38, which comprises the mouth portion of the respective cylindrical 'mixing chamber 39 in which the fuel is atomized. The axes of chamber 39 lie on and are spaced around the frustum of the conical face. Two series of ducts 41 and 42 extend through the body of the atomizing head to communicate the respective chambers 39 into communication with the passageways of the respective conduits 6 and 16. As shown each duct `41 extends co-axially of its respective chamber 39 and is formed with a bore which is relatively smaller than that of chamber 39, and connects the chamber 39 to the steam supply in well 50. Duets 42 are larger in size than duct V41 and they serve to supply fuel from passageway 20 to their respective chambers 39. As shown, ducts 42 extend from passageway 20 and toward their respective chamber 39 in a converging direction, and intersect each of their respective chambers 39. Preferably the axes of ducts 42 are disposed substantially normal to the inclined surface 34 of flange 29 and extend therethrough at an oblique angle toward chambers 39.

To facilitate manufacturing, the cone surface of bottom 51 of well 50 is preferably disposed in parallel relationship with the frusto-conical face of boss 37 so that ducts 41 may be drilled normal to both surfaces. Similar ducts 42 are drilled normal to surface 34 of the flange 29. After both seats of ducts 41 or 42 have been drilled, the chambers 39 are drilled out.

In operation fuel and steam are supplied through their respective supply lines (not shown) which connect aoraaaa to stub pipe 14 and elbow joint 8 respectively, and in turn to angular passageway 20 and the passageway of the inner conduit 6. At the atomizer head 10 the steam is discharged through ducts 41 atomizes the oil, supplied through ducts 42, in chamber 39 so that a fine spray of atomized fuel is discharged through the orifices 38 circumferentially spaced about the face of the atomizing head. The Spacing of chambers 39 serves to discharge a wide cone of atomized fuel into a combustion chamber or furnace.

A function of the circlip 19 is to limit movement of the outer conduit 16 in the direction of fuel discharge. Unless the clamp nut 22 is first removed, the outer portion of circlip 19 will move only until it abuts collar 52 of gland 21, and further movement may be prevented.

It will be apparent from FIG. l that the only part of the discharge end of the burner through which seepage of oil can occur from the annular passageway 20 is the joint between flange surface 34 and the bevelled end of the outer conduit 16. As this joint is backed up by the joints between cap nut 36 and the head 10 and the outer tube 16, leakage of fuel oil therethrough is unlikely. Any steam leakage from the passageway of conduit 6 to the fuel oil passageway 20 via the connection between the atomizer head 10 and the inner conduit 6 will contaminate the fuel and can seriously impair the operation of the burner. In the described burner, the danger of this steam leakage is greatly minimized Abecause the abutment joint formed between shoulder 53 and the end of conduit 66 is backed up by the labyrinthic effect of the screw connection between threaded boss 35 and inner conduit 6.

While in accordance with the provisions of the statutes I have illustrated and described herein the best form and mode of operation of the invention now known to me, those skilled in the art will understand that changes may be made in the form of the apparatus disclosed 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.

What is claimed is:

l. A liquid fuel burner comprising a sleeve housing, an inner conduit concentrically disposed within said housing to form a passageway for a first fluid, an outer conduit concentrically disposed with respect to said inner conduit and forming therebetween an annular passageway for a second fluid, means in said housing forming inlets for said respective passageways, a one-piece atomizing head connected to the discharge ends of said conduits, and a sealing means disposed between said outer conduit and said housing, said sealing means comprising inner and outer annular members having opposed complementary lateral surfaces and a compressible sealing ring wedge between said annular members, a collar arranged to bear on the outer face of said outer annular member to close the outer end of said housing about said conduits, and means for serially pressurizing said annular members and said sealing ring with said second fluid to enhance the sealing effect thereof.

2. A liquid fuel burner comprising a sleeve housing, an inner conduit concentrically disposed within said housing to form a passageway for a first fluid, an outer conduit concentrically disposed with respect to said inner conduit and forming therebetween an annular passageway for a second fluid, means in said housing forming inlets for said respective passageways, a one-piece atomizing head having a well in direct communication with said inner conduit and having a plurality of mixing chambers extending outwardly therefrom, said head being connected to the discharge ends of both of said conduits, and a sealing means disposed between said outer conduit and said housing, said sealing means comprising inner and outer annular members having opposed complementary lateral surfaces and a compressible sealing ring wedge between said annular members, a collar arranged to bear on the outer face of said outer annular member to close the outer end of said housing about said conduits, and means for serially pressurizing said annular members and said sealing ring with said second liuid to enhance the sealing eifect thereof.

3; A liquid fuel burner comprising a sleeve housing, an inner `conduit concentrically disposed within said housing to form a passageway for a iirst uid, an outer conduit concentrically disposed with respect to said inner conduit and forming therebetween an annular passageway for a second fluid, means in said housing forming inlets for said respective passageways, a one-piece atomizing head having a well in direct communication with said inner conduit and having a plurality of mixing chambers extending outwardly therefrom, said head being connected to the discharge ends of both of said conduits, and a sealing means disposed -between said outer conduit and said housing, said sealing means comprising inner and outer annular members having opposed complementary lateral surfaces and a compressible sealing ring wedge between said annular members, a collar arranged to bear on the outer face of said outer annular member to close the outer end of said housing about said conduits, and means including distributing holes through said inner annular member and said sealing ring for serially pressurizing said annular members and said sealing ring with said second Huid to enhance the sealing eect thereof.

4. A liquid fuel burner comprising sleeve housing having an internal shoulder intermediate the ends thereof, a anged coupler having a bore therein threaded to one end of said housing, an inner conduit concentrically disposed within said housing to deiine a passageway for an elastic fluid connected to said coupler, an outer conduit concentrically disposed with respect to said inner conduit forming therebetween an annular fuel passageway, said outer conduit having its inner end spaced from said flange coupler to form a fuel chamber communicating with said annular fuel passageway, means forming a fuel inlet communicating with said fuel inlet chamber, a means disposed between the outer conduit and said housing to form a seal therebetween, said sealing means including a pair of spaced annular sealing members having opposed complementary lateral surfaces, one of said members being disposed in abutting relationship to said internal shoulder of said sleeve, said one member having an annular groove in communication with said fuel chamber and a plurality of distributing holes in communication with said groove extending through the width of said one sealing member, an intermediate packing ring wedged between said annular sealing members whereby said packing ring is subjected to the pressure of said fuel in said fuel chamber to enhance the sealing elect thereof, a flanged collar fitted over the discharge end of said conduits for closing the other end of said sleeve and for urging said sealing means against said shoulder, an integrally formed atomizing head having a truste-conical face detachably connected to the discharge end of said conduits, said head having a well in direct communication with the passageway of the inner conduit, a plurality of mixing chambers having their longitudinal axes diverging in a direction away from said well, said mixing chambers terminating in said conical face to define therein a plurality of discharge openings, a series of ducts forming co-axial extensions of said chambers connecting said mixing chamber in communication with said well and said passageway connected thereto, and a second series of ducts converging toward said mixing chambers for connecting said mixing chambers in direct communication with said annular fuel passageway.

5. The invention as defined in claim 4 wherein a plurality of packing rings are disposed between said annular sealing members, each of said rings having an annular groove, and a plurality of distributing holes in communication therewith whereby the distributing holes of one ring serially connects to the groove of the next adjacent packing ring.

References Cited in the iile of this patent UNITED STATES PATENTS 1,061,562 Pierpont May 13, 1913 2,192,996 Fenzl Mar. l2, 1940 2,414,459 Fletcher Jan. 21, 1947 2,519,147 Miller Aug. l5, 1950 2,529,098 Noll Nov. 7, 1950 2,942,790 Starkey et al. June 28, 1960

Claims

1. A LIQUID FUEL BURNER COMPRISING A SLEEVE HOUSING, AN INNER CONDUIT CONCENTRICALLY DISPOSED WITHIN SAID HOUSING TO FORM A PASSAGEWAY FOR A FIRST FLUID, AN OUTER CONDUIT CONCENTRICALLY DISPOSED WITH RESPECT TO SAID INNER CONDUIT AND FORMING THEREBETWEEN AN ANNULAR PASSAGEWAY FOR A SECOND FLUID, MEANS IN SAID HOUSING FORMING INLETS FOR SAID RESPECTIVE PASSAGEWAYS, A ONE-PIECE ATOMIZING HEAD CONNECTED TO THE DISCHARGE ENDS OF SAID CONDUITS, AND A SEALING MEANS DISPOSED BETWEEN SAID OUTER CONDUIT AND SAID HOUSING, SAID SEALING MEANS COMPRISING INNER AND OUTER ANNULAR MEMBERS HAVING OPPOSED COMPLEMENTARY LATERAL SURFACES AND A COMPRESSIBLE SEALING RING WEDGE BETWEEN SAID ANNULAR MEMBERS, A COLLAR ARRANGED TO BEAR ON THE OUTER FACE OF SAID OUTER ANNULAR MEMBER TO CLOSE THE OUTER END OF SAID HOUSING ABOUT SAID CONDUITS, AND MEANS FOR SERIALLY PRESSURIZING SAID ANNULAR MEMBERS AND SAID SEALING RING WITH SAID SECOND FLUID TO ENHANCE THE SEALING EFFECT THEREOF.