US2752197A - Rotary nozzle for soot blowers and the like - Google Patents

Description

June 26, 1956 s. M. MARCO 2,752,197

ROTARY NOZZLE FOR SOOT BLOWERS AND THE LIKE Filed NOV. 25. 1953 INVENTOR. 5dr/V425 fe /y /zrca m' PM ORNE/S'.

United States Patent O ROTARY NOZZLE FOR SOOT BLOWERS AND THE LIKE Salvatore M. Marco, Columbus, Ohio, assigner to piamond Power Specialty Corporation, Lancaster, Ohio, a corporation of Ohio Application November 23, 1953, Serial No. 393,538

7 Claims. (Cl. 299-69) The present invention relates to cleaning devices of the soot blower type such as are employed to clean the heat exchanging surfaces of boilers and other heating devices. The invention is more particularly concerned with an improved rotary nozzle assembly adapted to be projected into desired proximity with respect to the heat exchanging surfaces and whereby a cleaning fluid such as air, steam, or a mixture of air and steam is projected from the nozzle against the surface to be cleaned.

Variously constructed types of soot blower nozzles have been proposed and used in the past. In most present day soot blowers the nozzles are xed to the lance tube, and may consist of holes or oriced plugs in the lance tube near the outer end. In some constructions the lance tube is rotatable, to project the cleaning fluid in an arc, and in some constructions the lance tube is both slidable and rotatable so that the soot blowing element can be retracted from the hotter zones of the combustion space, to prevent injury thereof by the high temperatures prevailing in said zones. It is not customary to attempt to mount the nozzles rotatably upon the lance tube, because of the difficulty in retaining lubricant for moving parts within the nozzle under such high temperatures. These temperatures, which range up to 2500 Fahrenheit and above, aifect even the most stable lubricating mediums such as, for example, graphite. This loss of lubrication for the moving parts of the nozzle subjects the mechanical components to extreme and early wear. The present invention aims to provide an improved nozzle which may be used within the high temperature regions of a water tube boiler without requiring lubricants for the relatively moving parts which are detrimentally affected by the high temperatures. struction all of the moving parts are floatingly mounted by the cleaning medium, commonly air, which is introduced between the bearings of the relatively moving parts during the cleaning operation, and the cleaning medium is also employed to rotate the nozzle on the lance tube.

A further object of the invention is to provide a rotaryv soot blower nozzle so designed that all lubricants which would be detrimentally affected by high temperatures are eliminated.

Still another object is to provide a simple, inexpensive and reliable rotary nozzle assembly for a soot blower utilizing very few mechanical components.

Another object is to provide an improved fluid driven rotary nozzle assembly.

Other objects and features of the invention will become apparent to those skilled in the art as the disclosure is made in the following detailed description of the invention as illustrated in the accompanying sheet of drawing in which:

' Fig. l is a side elevational view,l in section, of a preferred embodiment of the reaction-driven rotary nozzle assembly;

Fig. 2 is a cross sectional view taken substantially on the line of A-A of Fig. l and looking in the direction of 2,752,197 Patented im@ as, 1956 ICC the arrows showing the arrangement of the nozzles and the uid supply path to the nozzles;

Fig. 3 is a cross sectional view taken substantially on the line B-B of Fig. l and looking in the direction of the arrows showing the arrangement of the supply, distribution and feed passages for the cleaning medium acting to fioatingly mount the nozzle carrying body, and

Fig. 4 is a cross sectional View taken substantially on the line C-C of Fig. 1 and looking in the direction of the arrows showing a collecting channel and exit passages of the cleaning medium lubricating system.

Referring now to the drawings, wherein like reference characters designate like or corresponding parts throughout the several views there is shown in Fig. 1 a reactiondriven nozzle assembly 10, in section, adapted to` be connected to and carried by a lance tube 12 of the soot blower. Normally, the lance tube is so designed as to be connected to a cleaning fluid supply and, although not necessarily, is constructed to be mounted in a position in which it projects through the boiler wall. The cleaning medium is supplied to the nozzle through the lance tube and is controlled by any suitable means.

The reaction-driven rotary nozzle comprises a tubular manifold 14 extending throughout the length of the nozzle, a cap 16 secured to and closing the outer end of the manifold 14 for forming a cavity therein, and a nozzle body 18 completely surrounding the periphery of the manifold and journaled on said manifold with the nozzle body 18 and manifold 14 having a loose iit therebetween at the bearing surfaces. This loose it denes a clearance which will hereinafter be called a fluid bearing passage for terminology convenience. The nozzle body carries a pair of jet nozzles 20 and a pair of blower nozzles 22 equally spaced around the periphery of the nozzle body. As will become apparent, the cleaning fluid (which may be air or steam or a combination thereof although this is a matter of choice or judgment under the conditions prevailing) entering the manifold 14 from the lance 12 will be operative to floatingly mount the nozzle body on the manifold, produce a rotary motion of the nozzle body relative to the manifold by operation of the jet nozzles,

and further, clean the surfaces of the boiler tubes or In my improved nozzle conthe like by projected blasts of the cleaning fluid from the blower nozzles directed against the surfaces to be cleaned.

The manifold 14 of the rotary nozzle assembly comprises an elongated tubular member having an inner or entrancesection 24 wherein the cleaning fluid is introduced in the unit, an integral passage section 26 joining the inner section24 and a reduced central or bearing section 28, and an outer or end section 30. The inner section 24 is provided on its internal surface with a threaded portion'32 adapted to cooperate witha similarly threaded portion on the lance tube 12 or the like for securing purposes and for connection to the source of uid supply through the lance tube. The periphery of the manifold is provided with a smooth bearing surface for the juxtapositioned nozzle body adapted to rotate relative thereto.

A series of spaced, longitudinally extending distribution passages 36 (Figs. 1 and 3) are formed in the shell of the entrance section 24 and extend from an inner face 34 of the section to an annular abutment surface 38 defining the outer edge of the passage section 26 adjoining the reduced central section 28. A similar number of spaced, radially extending supply passages 40 are formed in the passage section 26 and extend from the interior cavity of the tubular manifold 14 to the periphery of the 36 is in turn connected, centrally, between the face 34 and the abutment surface 33 by a short, radially extending feed passage 42, to the clearance of bearing passage 44 formed by the loose fit of the elements 14- and 18.` The ends of the distribution and supply passages 36 at the rear face 34 and the outer ends of the drilled connecting passages 40 are closed by suitable means such as by welding while the feed passages 42 entering the bearing passage 44 and the distribution passages entering the bearing passage at the abutment surface 38 remain open.

A second series of spaced, radially extending supply passages 41 are formed in the central section 28 adjacent to the outer section 30 and extend from the interior cavity of the manifold directly to the periphery of the central section-28 whereby the cleaning mediumin the cavity of the manifold is operative to flow to the clearance or bearing passage 44 defined by the space between the periphery ofthe central section and the nozzle body.

The outer end 39 ofthe manifold is provided with an internal threaded portion 48 adapted to cooperate withY a similarly threaded portion formed on the cap 16 whereby the Vcap is threaded into the end-section 30 and functions to seal the outer tubular member of the manifold 14 to form a pressurized cavity therein.

The cap 16 comprises an inwardly opening hollow boss 52 having external threads-adapted to cooperate withV the threads48of the endsection 30 and a large annular head section 54. The internal opening of the boss 52 extends slightly into the head section 54. As shown in Fig; 4, the head section 54 is formed with a plurality of equally spaced, radially extending supply passages 56 which extend from the interior of the boss 52 to the periphery of the head section 54 and which passages are sealed at the periphery by suitable means such as welding. Each supply passage 56 is further provided with a short, longitudinally extending feed passage 58 joining the supply passage S6 with an abutment surface 60 of the cap 16. A plurality of Spanner holes 62 are provided around the periphery of the cap 16 for securement purposes although any suitable and conventional securing means may be employed.

Located around the periphery and in the wall of the central section 28, intermediate its ends thereof, are three equally spaced large outlet passages or apertures 46 adapted to provide a passageway for the cleaning medium from the cavity of the manifold 14 to the jet and blower nozzles and" 22 positioned on the nozzle body 18.

The nozzle body 18 carries the jet and blower nozzles 20 and 22 and comprises an elongated tubular member having an internal configuration similar to the` periphery of the manifold 14. The nozzle body is constructedy so as to-be rotatably mounted upon the manifold with the periphery of the manifold providing a bearing surface for the nozzle body. Aplurality of annular collecting' channel'si64 are formed along the internal surface of the-tubular nozzlev body. The collecting channels 64 are spaced axially along the bearing passage 44 provided by tlie small clearance between the elements 14 and 18. Each collecting channel is in turn connected to a plurality of spaced, radially extending exit passages 66 leading from the collecting channels to the exterior of the nozzlebody. ln-order that the cleaning medium flowing in the bearing passage 44 will flow smoothly out of the bearing passage, three collecting channels 64 are provided, one adjacent the shoulder portion 26, one adjacent the outer end at the wall 60 of cap 16, and one in aninterrnediate position. The collecting channels 64 and the exit passages 66 serve as an outlet for the air moving from the bearing passage 44 to the exterior of the nozzle.

Located centrally of the nozzle body 18, adjacent the outlet apertures 46 of the manifold and on its internal surface, as best seen in Fig. 2, is a large annular fluid supply channel 68 which functions to connect the jet and blower nozzles 20 and 22 carried by the nozzle body with the interior cavity of the manifold 14 through the apertures 46.

As shown in Fig. 2, the blower nozzles preferably comprise a cylindrical plug insert adapted to be mounted within a suitably threaded hole or the like formed in the nozzle body and connecting the air supply channel 68 with the exterior position of the nozzle body. The plug insert has a bore 70 therethrough, preferably of the expanding-type or venturinozzle type, which bore functions as an outlet or orifice for thev cleaning medium: projected against a surface to be cleaned. The expanding-type bore has a large outlet size area and a gradually reduced size area as it enters the inlet side of the plug. The reduced' or Yrestricted area portion of the nozzle bore is positioned at the point of connection with the supply channel for reasons hereinafter disclosed. An expandingtype nozzle outlet is preferred since it projects the maximum velocity of fluid relative to the supplied fluid pressure. A small radius-71 is formed on the nozzle body 19- adjacent the connection-of the bore 70 in the plug insert and the supply channel 68 to reduce the friction opposing the flow of fluid to the nozzle and to increase the effi ciency of the unit as anexpanding-type or venturi nozzle.

Spaced approx. apart from the blower nozzles andI positioned diametrically across from` each other are a pair of jet nozzles 20. The jet nozzles which also preferably* comprise cylindrical plug inserts adapted to be mounted'in-suitable holes formed in the nozzle body are conveniently secured to the nozzle body by suitable means such 'as-the thread means shown. Suitable Spanner holes.V 71`are providedon the external surface of the plug inserts to aid-in threadedly securing the members for the purpose. Each jet nozzle is provided with an axial bore 72 having the-outer end 74 closed and the inner end leadingv into the supply channel 68; A small discharge orificeAv 76 is formed in each of the plug inserts, normal to thel bore 72 and connecting the bore 72 with the exterior ofl ment with detachable plugr inserts, the jet nozzles 20 andi4 the blowers nozzles 22 may be formed integral with the nozzlenbody.under/certain circumstances depending upon' the; particular; design or application of theV rotary nozzle assembly;

Operation As the sootblower is placed intoV operation, the clean-- ing fluidwhich isA normally under pressure fiows throughA the lance-tubeV 12 to the nozzle assembly 10. The uide entering` theentrance sectionV 24' of the manifold, passes: throughthecavity'of the manifold, the.V outlet apertures 46 and-entersthe fluid supply channel 68 to the' jet and'A blower: nozzles.

The blower nozzles, as best seen in Figs. 1 and 2, are provided Withan. expanding-type or venturi nozzle which has an area of relatively restricted'size at the pointtof". connection withithe supply channel 68; This restriction will-provide aventuri effect' as' thecleaningfluid isreleased whereby a back pressure will be created. within the cavity-of the manifold. Also, due tothe restricted sizes ofthe orifices 76 and.78 of thejet nozzles, a further. back. pressure is created withinthe manifold 14. Thus. cleaning, uidwhich is under pressure, also enters the fluidV supply passages 40, 41 and S6, the, distribution passages 36 connected to the fluid supply passages 40-and flows to thel feed passages 42 and 58 to enter the clearance created between the loose-fit of the juxtapositioned elements of the manifold 14 and nozzle body 18 which clearanceV defines the bearing passage 44.` At the abutmllliS-SS'and 6tl`the1 constant, small'flow of' fluid leaving waaier the forward ends of passages 36 and 58 and impinging upon the juxtapositioned nozzle body 18 at these points, exerts a thrust force thereon and acts to provide a substantial air thrust bearing preventing end contact between the parts.

The fiuid travelling under pressure, created by the back pressure and the air supply, through the radially extending passages 40. and 41, the distribution and outlet passages 36 and 58 to the bearing passage 44, fills the bearing passage 44 with a constant fiow of fluid. Hence, the cleaning fluid is forced into the bearing passage 44 with the effect that the nozzle body substantially floats on the fiowing fiuid which provide a bearing and prevents contact between the parts. The flowing fiuid is collected in the collecting channels 64 and leaves the unit through the exit passages 66.

Fluid entering the bores 75 of the jet nozzles from the supply channel 68 escapes through the restricted orifices 76 and 78 and exerts reaction-thrust force to rotate the nozzle body relative to the manifold. The two jet nozzles, having the orifices 76 and 78 opposed, aid each other and provide a sufficient force to rotate the nozzle body swiftly, relative to the manifold.

It is desirable to emit the cleaning medium in relatively short blasts or puffs since soot, slag and other deposits are more effectively removed in this manner. It will be appreciated that the central section is provided with three, equally spaced large apertures 46 extending from the cavity in the manifold to the supply channel 68 of the nozzle body. As the nozzle body is rotated by the jet action of the nozzles, each of the blowers as Well as the jet nozzles will, in turn, be directly opposite one of the apertures 46, therefore, each nozzle will receive a full blast of fiuid, directly from the aperture 46, three times in every revolution of the nozzle body with the result that the jet nozzles 20 will apply periodically spurts of reaction-thrust force to the nozzle body and the blower nozzles 24 will project continuous blasts or puffs of fluid which may be effectively utilized to clean the heat exchanging surfaces of a boiler or the like.

While it will be apparent that the preferred embodiment of the invention herein described is well calculated to fulfill the objects and advantages first above stated, it will be appreciated that the invention is susceptible to variation, modification and change without departing from the fair meaning and proper scope of the appended claims.

What is claimed and desired to be protected by Letters Patent of the United States is:

1. A reactiondriven nozzle assembly adapted to be carried by a lance tube of a soot blower or the like, comprising a first body having an inner bearing surface, nozzle-defining means carried by said first body and operative to rotatably drive said first body and to emit blasts of cleaning fluid supplied thereto, a second body having an interior cavity, said first body being journaled on said second body with a loose-fit therebetween defining a bearing passage, a plurality of axially spaced radially extending fiuid feed passage means in said second body interconnecting said bearing passage and said interior cavity, means for introducing fluid under pressure to said interior cavity, whereby the fluid flows through said fluid feed passage means to said bearing passage for fioatingly mounting said first body on said second body, and a plurality of fiuid escape passage means extending through said first body at positions axially spaced from one another and from said feed passage means and also axially spaced from said nozzle-de1ining means.

2. A reaction-driven nozzle assembly adapted to be attached to a lance tube and carried thereby, comprising a first body having an inner bearing surface, a second body, said first body being journaled on said second body with a loose-fit therebetween defining a bearing passage, a plurality of spaced radially extending passage means in said second body interconnecting a cavity therein and said bearing passage, nozzle-defining means carried by said rst body and connected by an aperture in said second body with said cavity, means for introducing a fluid under pressure to said cavity, and a plurality of bearing fluid escape passages in and extending through said first body and axially spaced from said nozzle defining means to connect said bearing passage to the exterior of said first body, whereby the fiuid flows to said bearing passage for fioatingly mounting said first body on said second body and axially along said bearing passage and out through said escape passages, and also flows to said nozzle-defining means to rotatably drive said first body means relative to said second body means.

3. A reaction-driven nozzle assembly as defined in claim 2 wherein said bearing passage includes substantially cylindrical parts defining radial load bearing means and non-cylindrical parts defining thrust bearing means, said bearing fluid escape passages including portions communicating with said non-cylindrical parts.

4. A reaction-driven nozzle assembly adapted to be carried by a lance tube of a soot blower or the like, comprising a first ,tubular body member, a second tubular body member rotatably mounted on said first body member and having a loose fit therewith whereby a bearing passage is formed therebetween, said bearing passage including radial and thrust load bearing portions, a plurality of axially spaced radially extending fiuid feed passage means in said first body means extending from the cavity to said thrust load bearing portions, means for introducing a fluid under pressure to `said cavity, whereby the fiuid flows to said bearing passage to provide a substantially thrust bearing adjacent said abutments and floatingly mounts said second body on the first body, and nozzle-defining means carried by said second body means.

5. A reaction-driven rotary nozzle assembly adapted to be carried by a lance tube of a soot blower or the like comprising a first tubular body member having an inner bearing surface, a plurality of annular channel means formed on the interior bearing surface of said body member including a fiuid supply channel and collecting channels, nozzle-defining means carried by said body member including jet nozzles and blower nozzles each of which are connected with said fluid supply channel, said blower nozzles having an expanding-type orifice for projecting blowing fluid at high velocity, said jet nozzles having an interior bore and a restricted outlet orifice connected to said interior bore for applying a thrust force to the rst body means, a second tubular body member having one end closed and the other end connected to a source of blowing fiuid supply, the closed end defining a cavity therein, said first body member being journaled on said second body member with a loose-fit therebetween defining a bearing passage, said bearing passage being connected with said collecting channels, fluid passage means in the second body member extending between said cavity and said bearing passage means, whereby fiuid entering said cavity flows therefrom to said bearing passage for floatingly mounting said first body member on said second body member and to said jet and blower nozzles.

6. A reaction-driven nozzle assembly adapted to be carried by a lance tube of a soot blower or the like, comprising a first tubular body member having an entrance section connected to a source of fluid supply and a reduced central and end sections, means closing the end section and defining a cavity in said body member, said means having a like diameter as said entrance section whereby the ends of said central and end sections are defined by an abutment, a second tubular body member rotatably mounted on said central and end sections between said abutrnents, said first and second body members having a loose-fit therebetween defining a bearing passage, a plurality of annular channel means on said second body means adjoining said bearing passage including a Huidv supply channel and collecting channels, a jetnozzleY and a blower nozzle carried by said second body member each of whichV nozzles are connected to said uid supply channel, an expanding-type orifice in said blower nozzle for projecting blowing uid at high velocity, said blower nozzle having a restricting outlet areav adjoining said liuid supply channel, said jet nozzle having an interior bore and a restricted outlet orice connected to said bore for providing a reaction thrust force to the second body means, a plurality of uid passages in said iirst body member joining said cavity and said bearing passages at the abutments and the periphery of the central and end sections, means including said entrance section for admitting a blowing fluid within said cavity, whereby the blowing uid supplied to the cavity of the said second body member fows through said nozzles for providing blasts of duid and a thrust force to said second body member and through said fluid passages to said bearing passage adjacent the abutments and the periphery of the central and end sections for lioatingly mounting said body member 0n said iirst body member and for providing a substantially thrust bearing for said members, and exit passage means connecting said Vcollecting channels and the exterior of the unit for providing a uid passage out of the uniti 7. AV reaction-driven nozzle assembly as defined in" claim 2 wherein said bearing passage includes substantially cylindrical parts defining radialload bearing means and non-cylindrical parts defining thrustbearing means,

said bearing Huid escape passages including portions corn? municatingwith said non-cylindrical parts, and bearing uid feed passage means extendingthrough said secondY body from the cavity to the bearing surface at a plu` rality of positions axially spaced from the nozzle-defining means and also axially spaced from the bearing fluid escape passages.

References Citedin the'le of this patent UNITED STATES PATENTS

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