US2137253A - Apparatus for the fireside cleaning of boilers - Google Patents

Apparatus for the fireside cleaning of boilers Download PDF

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US2137253A
US2137253A US39948A US3994835A US2137253A US 2137253 A US2137253 A US 2137253A US 39948 A US39948 A US 39948A US 3994835 A US3994835 A US 3994835A US 2137253 A US2137253 A US 2137253A
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pipe
boiler
cleaning
pipes
tubes
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US39948A
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Beriah M Thompson
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    • FMECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F23COMBUSTION APPARATUS; COMBUSTION PROCESSES
    • F23JREMOVAL OR TREATMENT OF COMBUSTION PRODUCTS OR COMBUSTION RESIDUES; FLUES 
    • F23J3/00Removing solid residues from passages or chambers beyond the fire, e.g. from flues by soot blowers
    • F23J3/02Cleaning furnace tubes; Cleaning flues or chimneys
    • F23J3/023Cleaning furnace tubes; Cleaning flues or chimneys cleaning the fireside of watertubes in boilers

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  • My invention relates broadly to apparatus for cleaning combustion deposits from theflresides of boiler tubes.
  • the accumulation of such deposits is a normal occmrence and results in loss of boiler efliciency due tothe heat insulating action of the deposit on the tubes.
  • the present invention is an improvement on my Patent 1,812,375,'issued June 30, I931.
  • My said patent discloses a method and means whereby suchdeposits may be removed only when the boiler is substantially cold or cool enough to allow personnel to enter the combustion chamber to apply cleaning water directly to the tubes.
  • the invention of my said patent when employed with boilers lined with refractory material, required the use of a shield to prevent contact of the cleanin waterwith the refractory material. 7
  • the tubes may be cleaned while the boiler is hot and in use, and without the use of a shield, by regulating the amount and temperature of the cleaning liquid so that the heat within the boiler and about the tubes may transform it into steam' before it has travelled far enough to contact the refractory rous, penetration of the fluid in aliquid or vapcrous state andits rapid heating and expansion after penetration will aid in the cleaning action.
  • less water and time is required for the cleaning operation and the boiler need not be placed out of commission for the cleaning operation.
  • Sea water may be used to advantage in prac ticing my invention and boiler compound may be tional view of a conventional in the apparatus.
  • Fig. ' is an enlarged sectional end view of a pair of boiler tubes and the adjacent boiler wall showing the combustion deposit on the tubes and pipe union employed the action of the cleaning. fluid impingingthereon.
  • the shell of the boiler has provided therein a combustion space Ia occupying aportion of its fireside, through which extend a number of boiler tubes Ib. At a point preferably intermediate each row of tubes lb a series of holes I extend through the shell of the boiler to the fireside thereof.
  • cleaning water supply pipes 9a extend along near the top and bottom of the boiler, being supported thereon by brackets 9b.
  • the lower pipe 9a is provided with a valve 80. controlling the supply 4 of cleaning fluid thereto.
  • From each of the pipes 9a extends upwardly or downwardly a short length of pipea. against whose free end, with or withoutintermediate packing, is the beaded end of a goose-neck pipe I9a which is secured thereto by a pipe coupling 20.
  • a vertical pipe 60 Between the free ends of the opposite goose-neck pipes I9a and coupled thereto by pipe couplings 20 extends a vertical pipe 60.
  • branch pipes I 8a fitted with valves I811 and ending in nozzles 24a, extend at right angles thereto.
  • the spacing. of these branch pipes is such that the nozzle ends lie opposite the holes I in the boiler shell.
  • Each 'of the pipe couplings 2!] permits relative movement of the pipe ends coupled thereby.
  • Extending from each of the goose-neck pipes I9a aretwo rigid projections I9b. Each of these projections is provided with a socket. Extending between these projections and rigidly held thereby aretwo rods I9'c which run parallel to pipe 60.
  • the pipe 6c is provided with a handle lie for rotating it about its longitudinal axis and one of the rods I90 is provided with a handle 6d by means of which the whole assembly may be rotated about an axis running through pipes 20a.
  • This axis lies to one side of the row of holes I, as shown by Fig. 3.
  • As many rows of holes I as desired may be provided along the side of the boiler and a separate pipe 60 may be provided for each row of holes.
  • each pipe 66 with its gooseneck pipes Illa is adapted to be in a plane parallel withthe side of the boiler and to one side of the openings I therethrough, as shown in full lines in Fig. 3 with the nozzle end of each pipe I811 away from the row of holes I.
  • the cleaning water is admitted to the lower pipes 911 each through their valves 8a, thence the cleaning water rises through each of the lower gooseneck pipes I9a into each of the vertical pipes 60, and thence through valves [81) to their respective nozzle pipes IBa.
  • the valves I8b may each be opened one at a time to the desired extent while the valves 8a are open for cleaning the rows of tubes successively, or the different valves IBb may be opened, each to the desired extent, and the cleaning water turned on and off as desired by the valves 80,.
  • the nozzle ends 24a of each of the nozzle pipes lea are brought to register with their respective rows of openings I, in which position they are shown by dotted lines in Fig.
  • the gooseneck pipes Illa with their associated intermediate pipe 60, may be turned in their respective bearings in the inner and outer ends of each of the pairs of gooseneck pipes I90. until the nozzles of pipes 68a are brought into registration with theassociated row of openings I whereupon discharge of water from such nozzles through openings I will remove the deposit from adjacent tubes Ib; then by turning the assembly in its respective bearings the nozzle pipes I8a may be inserted into their respective openings 2 substantially to their valves IBb and a substantial angularity of application of the cleaning water from each row of nozzle pipes I811. through its row of holes I may be discharged upon the tubes lb by turning the respective pipes 60 somewhat upon the bearings provided at the opposite ends of each such pipe 60.
  • This latter angularity of discharge is limited by the relative sizes of the pipes 58a and the holes I through which they extend; but a substantial angularity of discharge is-readily obtainable without unduly large holes I.
  • the holes I are preferably oblong with their largest dimension at right angles to the axis of pipes 60, as indicated in Fig. 2. This increases the angularity of discharge of the cleaning water from nozzle pipes I8a in either of the aforesaid instances of whether the nozzle pipes 'ISc are projected into theirrespective openings I or remain adjacent the mouth of such openings.
  • the pipes may be merely the usual threaded connections and the threads turn upon each other to obtain the desired occasional limited relative turning of the respective pipes.
  • gooseneck pipe I9a being provided with beaded ends
  • the standard form of pipe coupling shown in Fig. 4 may also be employed for a turnable pipe coupling with substantial packing'intermediate the turnable coupling elements as therein shown.
  • Fig. shows at a an accumulation of combustion deposit suchas may occur upon certain of the tubes II) in heavy firing with protracted intervals between cleanings.
  • the widely flaring stream of liquid, with or without a typical cleaning preparation added thereto for rendering the liquid neutral or alkaline, coming from nozzle 24a, through opening I either directly contacts deposit a or is transposed into steam as indicated by the light dotted lines adjacent the surface of a.
  • the manipulation of nozzle 24a causes the liquid to be applied to deposit at different points along deposit a.
  • Typical-of all boilers the one shown in Figs. land 3 is provided with ablow off valve 5a connected to a low point in the water to be transposed into steam.
  • ablow off valve 5a connected to a low point in the water to be transposed into steam.
  • blow-down water contains minute solid particlesin suspension, which enter the boiler fireside with the velocity of the cleaning water and exert impact upon, as well as contribute to the removal of, the deposit and thus increase the efficiency of the cleaning operation.
  • said means comprising an outwardly extending pair of spaced apart arms each having parallel bearings at opposite ends, a revoluble pipe extending between and mounted in the bearings of the adjacent ends of said arms, bearing brackets receiving the bearings at the outer endsof said arms, said brackets being mounted to one side of said openings at intervals, at least one of said arms and its bearing bracket being hollow for supplying water to said pipe, lateral nozzles extending from said pipe one into each of said openings at intervals, and a rigid connection extending between said arms, there being such temperature gradient between such deposit and said jets exposed to the heat that said deposit is contracted and cleaned from the place adjacent which said liquid is applied, there being such relation of the heat within the boiler and the space between the tubes containing the deposit that the applied liquid may be transformed into steam before it may contact any injurable portion of the fire-sides.
  • the apparatus of claim 1 further characterized by an operating handle mounted upon said pipe.
  • Apparatus for cleaning combustion deposit from portions of boilers comprising in combination a pipe having at least one lateral outlet extending therefrom and adapted to receive a combustion deposit removing fluid, a portion of the boiler being provided with an opening therethrough for each of said lateral outlets, and means for pivotally mounting said pipe for movement about an axis located at a distance from and substaritiaJly parallel to the longitudinal axis of said pipe, said means comprising an outwardly extending pair of spaced apart arms each having parallel bearings at opposite ends, said pipe being mounted in the bearings at the adjacent ends of said arms, bearing brackets receiving the bearings at the remaining ends of said arms, said brackets being mounted to one side of the openings extending through a portion of the boiler, at least one of said bearing brackets and its cooperating arm being hollow to supply water to said pipe.

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  • Engineering & Computer Science (AREA)
  • Mechanical Engineering (AREA)
  • General Engineering & Computer Science (AREA)
  • Incineration Of Waste (AREA)

Description

NOV. 22, 1938. THOMPSON I 2,137,253
APPARATUS FOR THE F IRESIDE CLEANING OF BOILERS Fild Sept. 10, 1935 F 5 19b g INVENTOR BE RIAH M THOMPSON BY /K ATTORNEY Patented Nov. 22, 1938 T? QFFICE APPARATUSIFOR THE FIRESIDE CLEANING F BOILER-S j Beriah M. Thompson, United States Navy Application September 10, 1935, Serial No. 39,948
' 6 Claims.
(Granted under the: act of March3, 1883, as amended April 30, 1928;..370 0.G. .757)
My invention relates broadly to apparatus for cleaning combustion deposits from theflresides of boiler tubes. The accumulation of such deposits is a normal occmrence and results in loss of boiler efliciency due tothe heat insulating action of the deposit on the tubes. I
The present invention is an improvement on my Patent 1,812,375,'issued June 30, I931. My said patent discloses a method and means whereby suchdeposits may be removed only when the boiler is substantially cold or cool enough to allow personnel to enter the combustion chamber to apply cleaning water directly to the tubes. The invention of my said patent when employed with boilers lined with refractory material, required the use of a shield to prevent contact of the cleanin waterwith the refractory material. 7
By the use of my present invention the tubes may be cleaned while the boiler is hot and in use, and without the use of a shield, by regulating the amount and temperature of the cleaning liquid so that the heat within the boiler and about the tubes may transform it into steam' before it has travelled far enough to contact the refractory rous, penetration of the fluid in aliquid or vapcrous state andits rapid heating and expansion after penetration will aid in the cleaning action. In the use of my present invention, less water and time is required for the cleaning operation and the boiler need not be placed out of commission for the cleaning operation.
Sea water may be used to advantage in prac ticing my invention and boiler compound may be tional view of a conventional in the apparatus.
Fig. 'is an enlarged sectional end view of a pair of boiler tubes and the adjacent boiler wall showing the combustion deposit on the tubes and pipe union employed the action of the cleaning. fluid impingingthereon.
In the drawing, wherein like characters of reference indicate the same parts, the shell of the boiler has provided therein a combustion space Ia occupying aportion of its fireside, through which extend a number of boiler tubes Ib. At a point preferably intermediate each row of tubes lb a series of holes I extend through the shell of the boiler to the fireside thereof. 7
In the cleaning apparatus, as shown in Figs. 1 and 3, cleaning water supply pipes 9a extend along near the top and bottom of the boiler, being supported thereon by brackets 9b. The lower pipe 9a is provided with a valve 80. controlling the supply 4 of cleaning fluid thereto. From each of the pipes 9a extends upwardly or downwardly a short length of pipea. against whose free end, with or withoutintermediate packing, is the beaded end of a goose-neck pipe I9a which is secured thereto by a pipe coupling 20. Between the free ends of the opposite goose-neck pipes I9a and coupled thereto by pipe couplings 20 extends a vertical pipe 60. At spaced intervals along this pipe short branch pipes I 8a fitted with valves I811 and ending in nozzles 24a, extend at right angles thereto. The spacing. of these branch pipes is such that the nozzle ends lie opposite the holes I in the boiler shell. Each 'of the pipe couplings 2!] permits relative movement of the pipe ends coupled thereby. Extending from each of the goose-neck pipes I9a aretwo rigid projections I9b. Each of these projections is provided with a socket. Extending between these projections and rigidly held thereby aretwo rods I9'c which run parallel to pipe 60. The pipe 6c is provided with a handle lie for rotating it about its longitudinal axis and one of the rods I90 is provided with a handle 6d by means of which the whole assembly may be rotated about an axis running through pipes 20a. This axis lies to one side of the row of holes I, as shown by Fig. 3. As many rows of holes I as desired may be provided along the side of the boiler and a separate pipe 60 may be provided for each row of holes.
When not in use for cleaning the deposits from the tubes of the boiler, each pipe 66 with its gooseneck pipes Illa is adapted to be in a plane parallel withthe side of the boiler and to one side of the openings I therethrough, as shown in full lines in Fig. 3 with the nozzle end of each pipe I811 away from the row of holes I. By the independent turning of their respective pipe 60 in bearingsprovided at opposite ends of each pipe 60 by the coupling members 20 with the nozzle ends of pipes I8a. away from each row of holes I, such holes may be employed, when open therefonas peepholes to ascertain the condition of the tubes lb as to deposit and otherwise. When in use for cleaning the boiler, with the structure indicated in Figs. 1 and 3, the cleaning water is admitted to the lower pipes 911 each through their valves 8a, thence the cleaning water rises through each of the lower gooseneck pipes I9a into each of the vertical pipes 60, and thence through valves [81) to their respective nozzle pipes IBa. The valves I8b may each be opened one at a time to the desired extent while the valves 8a are open for cleaning the rows of tubes successively, or the different valves IBb may be opened, each to the desired extent, and the cleaning water turned on and off as desired by the valves 80,. The nozzle ends 24a of each of the nozzle pipes lea are brought to register with their respective rows of openings I, in which position they are shown by dotted lines in Fig. 3, by the turning of pipe 60 upon its bearings in the pipe coupling members 20 at opposite ends of pipe 60. The angle at which each nozzle end 24a discharges the cleaning water through the openings I is controlled by the turning of each of the pipes 60 and its opposite gooseneck pipes I9a about the outer-ends of the gooseneck pipe I911. The thus cbtained angularity. of discharge of approximately 150 of the water from each nozzle tip E ia within the boiler from each of the opposite sides of the boiler, affords a wide range of the application of the cleaning water applied over a substantial length of many of the boiler tubes Eh which are required to have their exterior deposits removed.
The gooseneck pipes Illa, with their associated intermediate pipe 60, may be turned in their respective bearings in the inner and outer ends of each of the pairs of gooseneck pipes I90. until the nozzles of pipes 68a are brought into registration with theassociated row of openings I whereupon discharge of water from such nozzles through openings I will remove the deposit from adjacent tubes Ib; then by turning the assembly in its respective bearings the nozzle pipes I8a may be inserted into their respective openings 2 substantially to their valves IBb and a substantial angularity of application of the cleaning water from each row of nozzle pipes I811. through its row of holes I may be discharged upon the tubes lb by turning the respective pipes 60 somewhat upon the bearings provided at the opposite ends of each such pipe 60. This latter angularity of discharge is limited by the relative sizes of the pipes 58a and the holes I through which they extend; but a substantial angularity of discharge is-readily obtainable without unduly large holes I. The holes I are preferably oblong with their largest dimension at right angles to the axis of pipes 60, as indicated in Fig. 2. This increases the angularity of discharge of the cleaning water from nozzle pipes I8a in either of the aforesaid instances of whether the nozzle pipes 'ISc are projected into theirrespective openings I or remain adjacent the mouth of such openings.
Instead of the joints heretofore described between pipes I9a, 20a as well as. between opposite ends of pipes 60 and I9a, the pipes may be merely the usual threaded connections and the threads turn upon each other to obtain the desired occasional limited relative turning of the respective pipes.
Instead of gooseneck pipe I9a being provided with beaded ends, the standard form of pipe coupling shown in Fig. 4 may also be employed for a turnable pipe coupling with substantial packing'intermediate the turnable coupling elements as therein shown.
Fig. shows at a an accumulation of combustion deposit suchas may occur upon certain of the tubes II) in heavy firing with protracted intervals between cleanings. The widely flaring stream of liquid, with or without a typical cleaning preparation added thereto for rendering the liquid neutral or alkaline, coming from nozzle 24a, through opening I either directly contacts deposit a or is transposed into steam as indicated by the light dotted lines adjacent the surface of a. The manipulation of nozzle 24a causes the liquid to be applied to deposit at different points along deposit a.
Typical-of all boilers, the one shown in Figs. land 3 is provided with ablow off valve 5a connected to a low point in the water to be transposed into steam. Upon the boiler side of said valve 5a or to any other desirable point where hot water 'is available in boilers, maintaining its contained water at an insuificient pressure and temperature to be converted into steam when released at substantially atmospheric pressure, I connect a pipe ,5 having valve. 51), which pipe 5 leads to pipes. 60 where the cleaning water is not desired from a source without the boiler.
In taking the cleaning water from the bottom blow-off or otherccnnection from preferably the low point of the boiler, it combines into a single operation the otherwise separate tasks of blowingdown the boiler to clear same of sediment and of cleaning the boiler -fireside by my improved method, and thus usefully employs the blowdown water which otherwise would be wasted.
A further'advantage of using the blow-down water for said cleaning I have found to be that the blow-down water contains minute solid particlesin suspension, which enter the boiler fireside with the velocity of the cleaning water and exert impact upon, as well as contribute to the removal of, the deposit and thus increase the efficiency of the cleaning operation.
This invention may be used by andfor the Government of the United States of America for governmental purposes without. the payment of any royalty thereon or therefor;
Having now so fully described my invention in its method and apparatus aspects that others skilled in'theart may thereupon be enabled to readily-make and use the same, what I claim is:- lkA'pparatus for cleaning combustion deposit from the firesides of boilers while being subjected to substantial working heat, comprising, in combinatioma boiler having tubes and a casing provided with fire-sides therein and openings through the casing at intervals, and means for applying through said openings liquid in exposed jets under pressure adjacent the hot combustion deposit upon said. tubes, said means comprising an outwardly extending pair of spaced apart arms each having parallel bearings at opposite ends, a revoluble pipe extending between and mounted in the bearings of the adjacent ends of said arms, bearing brackets receiving the bearings at the outer endsof said arms, said brackets being mounted to one side of said openings at intervals, at least one of said arms and its bearing bracket being hollow for supplying water to said pipe, lateral nozzles extending from said pipe one into each of said openings at intervals, and a rigid connection extending between said arms, there being such temperature gradient between such deposit and said jets exposed to the heat that said deposit is contracted and cleaned from the place adjacent which said liquid is applied, there being such relation of the heat within the boiler and the space between the tubes containing the deposit that the applied liquid may be transformed into steam before it may contact any injurable portion of the fire-sides.
2. The apparatus of claim 1 further characterized by an operating handle mounted upon said pipe.
3. Apparatus for cleaning combustion deposit from portions of boilers comprising in combination a pipe having at least one lateral outlet extending therefrom and adapted to receive a combustion deposit removing fluid, a portion of the boiler being provided with an opening therethrough for each of said lateral outlets, and means for pivotally mounting said pipe for movement about an axis located at a distance from and substaritiaJly parallel to the longitudinal axis of said pipe, said means comprising an outwardly extending pair of spaced apart arms each having parallel bearings at opposite ends, said pipe being mounted in the bearings at the adjacent ends of said arms, bearing brackets receiving the bearings at the remaining ends of said arms, said brackets being mounted to one side of the openings extending through a portion of the boiler, at least one of said bearing brackets and its cooperating arm being hollow to supply water to said pipe.
4. The apparatus of claim 3 characterized by an operating member extending laterally from said pipe.
5. The apparatus of claim 3 characterized by a rigid connection extending between said pair of arms. 7 n
6. The apparatus of claim 3 characterized by a rigid connection extending between said pair of M BERIAI-I M. THONIPSON.
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Cited By (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2618284A (en) * 1946-11-22 1952-11-18 United States Steel Corp Heat-treatment of hardenable steel
US3110300A (en) * 1961-04-26 1963-11-12 Universal Oil Prod Co Catalytic gas oxidizing and fluid heating apparatus
US3311092A (en) * 1965-12-20 1967-03-28 Combustion Eng Type sootblower for cleaning the tubes of furnace walls
US3661124A (en) * 1970-06-19 1972-05-09 Foster Wheeler Corp Apparatus and process for slag deposit removal
US4714053A (en) * 1986-07-23 1987-12-22 Perry Richard C Water heater cleaning apparatus

Cited By (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2618284A (en) * 1946-11-22 1952-11-18 United States Steel Corp Heat-treatment of hardenable steel
US3110300A (en) * 1961-04-26 1963-11-12 Universal Oil Prod Co Catalytic gas oxidizing and fluid heating apparatus
US3311092A (en) * 1965-12-20 1967-03-28 Combustion Eng Type sootblower for cleaning the tubes of furnace walls
US3661124A (en) * 1970-06-19 1972-05-09 Foster Wheeler Corp Apparatus and process for slag deposit removal
US4714053A (en) * 1986-07-23 1987-12-22 Perry Richard C Water heater cleaning apparatus

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