Classifications

• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F22—STEAM GENERATION
  • F22B—METHODS OF STEAM GENERATION; STEAM BOILERS
  • F22B21/00—Water-tube boilers of vertical or steeply-inclined type, i.e. the water-tube sets being arranged vertically or substantially vertically
  • F22B21/02—Water-tube boilers of vertical or steeply-inclined type, i.e. the water-tube sets being arranged vertically or substantially vertically built-up from substantially straight water tubes
  • F22B21/04—Water-tube boilers of vertical or steeply-inclined type, i.e. the water-tube sets being arranged vertically or substantially vertically built-up from substantially straight water tubes involving a single upper drum and a single lower drum, e.g. the drums being arranged transversely
  • F22B21/08—Water-tube boilers of vertical or steeply-inclined type, i.e. the water-tube sets being arranged vertically or substantially vertically built-up from substantially straight water tubes involving a single upper drum and a single lower drum, e.g. the drums being arranged transversely the water tubes being arranged sectionally in groups or in banks, e.g. bent over at their ends
  • F22B21/081—Water-tube boilers of vertical or steeply-inclined type, i.e. the water-tube sets being arranged vertically or substantially vertically built-up from substantially straight water tubes involving a single upper drum and a single lower drum, e.g. the drums being arranged transversely the water tubes being arranged sectionally in groups or in banks, e.g. bent over at their ends involving a combustion chamber, placed at the side and built-up from water tubes
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F22—STEAM GENERATION
  • F22B—METHODS OF STEAM GENERATION; STEAM BOILERS
  • F22B37/00—Component parts or details of steam boilers
  • F22B37/001—Steam generators built-up from pre-fabricated elements

Definitions

• This invention relates to steam generators, and more specifically, to package boilers of the type that embody a unitary construction.
• package boilers It has long been known in the prior art to provide package boilers.
• a characteristic of package boilers is that they are often shipped from the place of fabrication as assembled units. It is, therefore, necessary that the assembled unit, i.e., the package boiler, be structurally rigid so that when the assembled unit is being handled and moved about there will be no appreciable relative movement between the elements of the assembled unit since this would cause cracking or destruction of the assembled unit and possible leakage of the connection of the tubes of the package boiler with the steam drum and water drum thereof.
• the package boiler require minimum maintenance.
• This wall terminates a short distance from the rear wall of the furnace and also forms the side wall of a horizontal gas pass positioned along the furnace, and which is in communication with the furnace through the passage formed between the end of the side wall and rear wall.
• the opposite ends of the aforementioned side-by-side tubes are connected to upper and lower drums, respectively, which extend longitudinally of the gas pass and are interconnected by a convection tube bank positioned within the gas pass.
• interconnecting these drums are tubes that extend along the roof of the furnace down the other side wall and along or within the bottom of the furnace.
• the front and rear walls of the furnace are similarly lined with tubes and these latter tubes interconnect the two drums by extending diagonally from the upper and lower ends of the respective front and rear walls to a point immediately adjacent the respective upper and lower drums and thence into these drums.
• the furnace is fired through a suitable opening in the front wall and the combustion gases generated by the burning of fuel within the furnace pass around the rear end of the side wall that separates the furnace and the gas pass, and then flow through the gas pass and into a suitable chimney or stack. Heat generated by this burning of fuel is absorbed by the various tubes, and steam is thus generated in the known manner.
• a steam generator which comprises a housing having a top provided with a gas outlet, which can be positioned either at the front or the rear of the housing to suit individual site conditions, a bottom, left and right sides, and a front and back.
• a gas outlet which can be positioned either at the front or the rear of the housing to suit individual site conditions, a bottom, left and right sides, and a front and back.
• an upper manifold and a lower manifold extend substantially parallel to the top, bottom and side walls; between these two manifolds, two sets of tubes are displayed.
• Each set of tubes is identical, the tubes being bent serpentinely so as to form a plurality of superimposed gas passages; at least two tubes of each set are bent differently so as to form access openings to the passages above and below.
• a third such additional characteristic that such a new and improved package boiler of unitary construction would desirably possess is the capability whereby any one of the three standard profiles thereof can be customized as can the boiler length and the number of tubes wide in the boiler bank in order to thereby meet the user's specific steam flow requirement as well as the user's specific pressure and temperature requirements.
• a fourth such additional characteristic that such a new and improved package boiler of unitary construction would desirably possess is the capability of embodying any one of the following options, i.e., rigidized ceramic fiber furnace front walls for light oil or natural gas firing or heavy duty castable refractory front walls for heavy oil and other special fuels, or a fully water cooled front wall.
• a fifth such additional characteristic that such a new and improved package boiler of unitary construction would desirably possess is the capability of embodying fin-welded furnace "D" tubes and rear walls in order to thereby ensure a gas-tight combustion zone and uniform heat distribution to the tubes and fins, and with the fin spacing between adjacent furnace tubes being a maximum of one inch in order to thereby eliminate overheating and cracking problems associated with designs having wider tube spacing in the furnace area.
• a sixth such additional characteristic that such a new and improved package boiler of unitary construction would desirably possess is the capability of embodying unheated downcomers in order to thereby assure positive circulation for faster transient response time and increased water level stability.
• a seventh such additional characteristic that such a new and improved package boiler of unitary construction would desirably possess is the capability of embodying improved steam drum internals in order to thereby provide final polishing of the steam to maximum dryness and reduce carryover of boiler chemicals to the absolute minimum when used in conjunction with a proper boiler feedwater conditioning program.
• An eighth such additional characteristic that such a new and improved package boiler of unitary construction would desirably possess is the capability of embodying large diameter/capacity upper drums in order to thereby enhance response to normal feedwater flow fluctuations associated with plant transients and other short term feed flow interruptions.
• a ninth such additional characteristic that such a new and improved package boiler of unitary construction would desirably possess is the capability of embodying self- supporting, fully drainable superheaters that are located behind a row of screen tubes such as to thereby provide a balanced ratio of radiant and convective heat input in order to thereby produce a relatively stable steam temperature characteristic over a wide load range as well as reduced superheater metal temperature. It is, therefore, an object of the present invention to provide a new and improved steam generator in the form of a package boiler that is of unitary construction.
• Another object of the present invention is to provide such a new and improved package boiler of unitary construction that is characterized in that it possesses the capability whereby any one of the three standard profiles thereof can be customized as can the boiler length and the number of tubes wide in the boiler bank in order to thereby meet the user's specific steam flow requirements as well as the user's specific pressure and temperature requirements.
• a still another object of the present invention is to provide such a new and improved package boiler of unitary construction that is characterized in that it possesses the capability of embodying any one of the following options, i.e., rigidized ceramic fiber furnace front walls for light oil or natural gas firing, or heavy duty castable refractory front walls for heavy oil and other special fuels, or a fully water cooled front wall.
• a further object of the present invention is to provide such a new and improved package boiler of unitary construction that is characterized in that it possesses the capability of embodying fin-welded "D" tubes, baffle wall tubes and rear walls in order to thereby ensure a gas-tight combustion zone and uniform heat distribution to the tubes and fins, and with the fin spacing between furnace tubes being a maximum of one inch in order to thereby eliminate overheating and cracking problems associated with designs having wider tube spacing in the furnace area.
• a still further object of the present invention is to provide such a new and improved package boiler of unitary construction that is characterized in that it possesses the capability of embodying unheated downcomers in order to thereby assure positive circulation for faster transient response time and increased water level stability.
• Yet an object of the present invention is to provide such a new and improved package boiler of unitary construction that is characterized in that it possesses the capability of embodying improved steam drum internals in order to thereby provide final polishing of the steam to maximum dryness and reduce carryover of boiler chemicals to the absolute minimum when used in conjunction with a proper boiler feedwater conditioning program.
• Yet a further object of the present invention is to provide such a new and improved package boiler of unitary construction that is characterized in that it possesses the capability of embodying large diameter/capacity upper drums in order to thereby enhance response to normal feedwater flow fluctuations associated with plant transients and other short term feed flow interruptions.
• Yet another object of the present invention is to provide such a new and improved package boiler of unitary construction that is characterized in that it possesses the capability of embodying self- supporting fully drainable superheaters that are located behind a row of screen tubes such as to thereby provide a balanced ratio of radiant and convective heat input in order to thereby produce a relatively stable steam temperature characteristic over a wide load range as well as reduced superheater metal temperature.
• a steam generator in the form of a package boiler that embodies a unitary construction, and which in particular is characterized in that when compared to prior art units this package boiler of unitary construction requires less auxiliary power, provides drier steam, and reduces maintenance and field installation time, and can be inexpensively tailored to meet the user's specific needs.
• the subject package boiler of unitary construction includes a furnace, unheated downcomers, a large diameter steam drum, water drum, improved steam drum internals and as an option a self-supporting fully drainable superheater.
• the furnace based on the particular pressure and temperature conditions required thereof embodies a predetermined standard profile selected from a plurality of standard profiles collectively capable of providing within a range of design pressures up to 1050 psig and a range of design superheater outlet temperatures up to 750 degrees F. steam production within a range of 20,000 to 180,000 pounds per hour, and based on the nature of the fuel to be fired therewith embodies a front wall of predetermined construction selected from front walls of rigidized ceramic fiber for use when the fuel being fired therewith is light oil and natural gas, front walls of heavy duty castable refractory for use when the fuel being fired therewith is heavy oil and other special fuels, and front walls that are fully water cooled.
• the furnace is comprised of fin-welded furnace tubes and rear walls in order to thereby ensure a gas-tight combustion zone and uniform heat distribution to the furnace tubes and fins.
• the fin spacing between adjacent tubes is a maximum of one inch in order to thereby eliminate overheating and cracking problems associated with designs having wider tube spacing in the furnace area.
• the unheated downcomers are designed to be operative to assure positive circulation in order to thereby achieve faster transient response time and increased water level stability.
• the large diameter steam drum is designed to be operative to thereby enhance response to normal feedwater flow fluctuations associated with plant transients and other short term feed flow interruptions.
• the improved steam drum internals are designed to be operative to thereby provide final polishing of the steam to maximum dryness and to reduce carryover of boiler chemicals to the absolute minimum when used in conjunction with a proper boiler feedwater conditioning program.
• the self-supporting fully drainable superheater is located behind a row of screen tubes such as to thereby provide a balanced ratio of radiant and convective heat input in order to thereby produce a relatively stable steam temperature characteristic over a wide load range as well as reduced superheater metal temperature.
• Figure 1 is a plan view, partially in section, of a package boiler of unitary construction, constructed in accordance with the present invention
• Figure 2 is a cross-sectional view of the front wall of the package boiler of unitary construction of Figure 1 constructed in accordance with the present invention, taken substantially along the line 2-2 in Figure 1;
• Figure 3 is a cross-sectional view of a first portion of the front wall of the package boiler of unitary construction of Figure 2 constructed in accordance with the present invention, taken substantially along the line 3-3 in Figure 2;
• Figure 4 is a cross-sectional view of a second portion of the front wall of the package boiler of unitary construction of Figure 2 constructed in accordance with the present invention, taken substantially along the line 4-4 in Figure 2;
• Figure 5 is a cross-sectional view of a third portion of the front wall of the package boiler of unitary construction of Figure 2 constructed in accordance with the present invention, taken substantially along the line 5-5 in Figure 2;
• Figure 6 is a cross-sectional view of the package boiler of unitary construction of Figure 1 constructed in accordance with the present invention, taken substantially along the line 6-6 in Figure 1 ;
• Figure 7 is a cross-sectional view of the rear wall of the package boiler of unitary construction of Figure 1 constructed in accordance with the present invention, taken substantially along the line 7-7 in Figure 1 ;
• Figure 8 is a cross-sectional view of another embodiment of a front wall employable in the package boiler of unitary construction of Figure 1 constructed in accordance with the present invention
• Figure 9 is a side elevational view, partially in section, of the upper steam drum of a package boiler of unitary construction, constructed in accordance with the present invention
• Figure 10 is a cross-sectional view of the upper steam drum of Figure 9 of a package boiler of unitary construction, constructed in accordance with the present invention, taken substantially along the line 10-10 in Figure 9;
• Figure 11 is a cross-sectional view of the upper steam drum of Figure 9 of a package boiler of unitary construction, constructed in accordance with the present invention, taken substantially along the line 11-11 in Figure 9;
• Figure 12 is a plan view of a portion of a package boiler of unitary construction, constructed in accordance with the present invention, illustrating a superheater therewithin.
• the package boiler 10 embodies a unitary construction, i.e., is designed so as to be capable of being assembled into an integral unit at the place of manufacture and so as to be capable thereafter of being transported as an integral unit from the place of manufacture to the location whereat it is desired to utilize the package boiler 10.
• package boilers 10 constructed in accordance with the present invention that are capable of steam production from 60,000 pounds per hour up to 180,000 pounds per hour are designed so as to be shippable as an integral unit by rail whereas package boilers 10 constructed in accordance with the present invention that are capable of steam production up to 60,000 pounds per hour are designed so as to be shippable as an integral unit by truck.
• the package boilers 10 embody sufficient structural rigidity such that when the package boilers 10, after being assembled into an integral unit, are being handled and moved about there will be no appreciable relative movement between the various elements that collectively comprise a package boiler 10.
• the package boiler 10 as best understood with reference to Figures 2, 6 and 7 of the drawing embodies essentially a D- shaped configuration.
• the package boiler 10 as best understood with reference to Figure 1 of the drawing, embodies a furnace portion, generally designated in Figure 1 by the reference numeral 12.
• furnace portion 12 for purposes of ease of description, will be deemed to comprise that portion of the package boiler
• the walls 14, 16, 18 and 20 residing within the four walls, generally designated by the reference numerals 14, 16, 18 and 20, respectively, i.e., within the front wall 14, the two side walls 16 and 18, and the rear wall 20.
• the walls 14, 16, 18 and 20 are designated by the reference numerals 14, 16, 18 and 20 respectively, i.e., within the front wall 14, the two side walls 16 and 18, and the rear wall 20.
• the four walls 14, 16, 18 and 20 of the package boiler 10 are themselves preferably encased, as best seen with reference to Figure
• a mineral fiber blanket generally designated by the reference numeral 30, of suitable thickness is preferably selectively interposed between the four walls 14, 16, 18 and 20 and the casing members 22, 24, 26 and 28 at specified locations therebetween.
• the mineral fiber blanket is preferably selectively interposed between the four walls 14, 16, 18 and 20 and the casing members 22, 24, 26 and 28 at specified locations therebetween.
• the casing members 22, 24, 26 and 28 are intended to function as insulation, i.e., to effectuate the insulation of the casing members 22, 24, 26 and 28 from the four walls 14, 16, 18 and 20 in order to thereby ensure that insofar as the temperature thereof is concerned the casing members 22, 24, 26 and 28 do not pose a danger to anyone that might accidentally come in contact therewith while the package boiler 10 is being operated.
• the side walls 16 and 18 and the rear wall 20 of the package boiler 10 are each comprised of a multiplicity of tubes, denoted in Figure 1 by the reference numeral 32, that are interconnected by fins, denoted in
• each of the tubes 32 is comprised of a multiplicity of tubes 32 that are interconnected by fins 34. More specifically, each of the tubes 32, be it the tubes 32 of the side walls 16 and 18 or the tubes 32 of the rear wall 20 or the tubes 32 of the front wall 14, has fins 34 that project outwardly therefrom on two opposite sides thereof such that the fins of adjoining tubes 32 can be welded together and/or fins welded to adjacent tubes in order to thereby create a gas-tight combustion zone therewithin and also in order to thereby concomitantly ensure that uniform heat distribution is provided to the tubes 32 and fins 34.
• the fins 34 are suitably dimensioned such that when- the fins 34 of adjoining tubes 32 are welded together the spacing between adjoining tubes 32 created by the existence therebetween of the fins 34 is a maximum of one inch.
• the fin spacing between adjoining tubes 32 is made to be a maximum of one inch in order to ensure that the overheating and cracking problems, which are known to disadvantageously characterize prior art forms of package boilers, that in their furnace area have wider spacing between the tubes thereof, are eliminated in the case of the package boiler 10 that is the subject of the present invention.
• the package boiler 10 embodies in the interior thereof a partially extending wall, generally designated by the reference numeral 36 in Figure 1 of the drawing, comprised of a multiplicity of the tubes 32 that in the same manner as that which has been described hereinbefore in connection with the discussion of the nature of the construction of the walls 14, 16, 18 and 20 of the package boiler 10 are interconnected one to another by means of the welding together of the fins 34 with which for this purpose each of the tubes 32 is suitably provided.
• an upper stream drum generally designated in Figure 2 by the reference numeral 40, to which further reference will be had hereinafter
• a water drum associated with the bottom section 38, in suitably supported relation thereto, of the package boiler 10 constructed in accordance with the present invention, as best understood with reference to Figure 2 of the drawing, is a water drum, generally designated in Figure 2 by the reference numeral 42, to which further reference will be had subsequently.
• the top section 36 of the package boiler 10, apart from the upper steam drum 40 that is associated therewith, in accordance with the present invention is deemed to encompass a wall-like surface, denoted generally in Figure 2 by the reference numeral 44, which in the same manner as, for instance, the side walls 16 and 18 to which reference has been had hereinbefore is comprised of a multiplicity of tubes 32 that are interconnected by fins 34, the latter not being shown in Figure 2 in the interest of maintaining clarity of illustration therein; a casing member, denoted in Figure 2 by the reference numeral 46, which in terms both of its construction and mode of operation is like the casing members 22,24, 26 and 28 to which reference has been had hereinbefore, is suitably positioned in surrounding relation to the wall-like surface 44; and the portion of the mineral fiber blanket 30, which is suitably interposed between the wall-like surface 44 and the casing member 46.
• the bottom section 38 of the package boiler 10, apart from the water drum 42 that is associated therewith, in accordance with the present invention is deemed to encompass a wall-like surface, denoted generally in Figure 2 by the reference numeral 48, which in the same manner as, for instance, the side walls 16 and 18 to which reference has been had hereinbefore is comprised of a multiplicity of tubes 32 that are interconnected by fins 34, the latter not being shown in Figure 2 in the interest of maintaining clarity of illustration therein; a support structure, denoted generally in Figure 2 by the reference numeral 50, to which further reference will be had hereinafter; and the portion of the mineral fiber blanket 30, which is suitably interposed between the wall-like surface
• the support structure 50 is intended to function as a support for the package boiler 10 of the present invention as well as a means of providing the bottom section 38 of the package boiler 10 with a horizontally extending surface in order to thereby facilitate the placement of the package boiler
• the support structure 50 in accordance with the illustrated embodiment thereof as depicted in Figure 2 of the drawing includes a plurality of structural members denoted for ease of identification by the reference numerals 52 and 52a, respectively, which are suitably configured so as to be operative to convert the vertically extending inclination of the wall-like surface 48 into a horizontally extending surface as depicted in Figure 2, and which are designed so as to embody sufficient structural rigidity in order that the weight of the package boiler 10 is capable of being supported therewith.
• the structural member 52 and 52a are suitably configured so as to be operative to convert the vertically extending inclination of the wall-like surface 48 into a horizontally extending surface as depicted in Figure 2, and which are designed so as to embody sufficient structural rigidity in order that the weight of the package boiler 10 is capable of being supported therewith.
• the structural member denoted for ease of identification by the reference numerals 52 and 52a, respectively, which are suitably configured so as to be operative to convert the vertically extending inclination of the
• flange-like surface 54 which is designed to cooperatively engage an L-shaped member 56, which is suitably positioned in mounted relation on the wall-like surface 48 in order to thereby be operative to effect a locking relationship between the L-shaped member 56 and the flange-like surface 54.
• Figure 8 of the package boiler 10 constructed in accordance with the present invention regardless of whether the front wall 14 comprises as depicted in Figure 2 of the drawing a ceramic fiber furnace front wall or a heavy duty refractory front wall, or comprises a fully water cooled furnace front wall 14' as depicted in Figure 8 of the drawing, has formed therewithin an opening, denoted generally by the reference numeral 58 in both Figures 2 and 8.
• the opening 58 is suitably dimensioned such that a burner, not shown in the interest of maintaining clarity of illustration in the drawing, may be supported in mounted relation therewithin.
• such a burner which may take the form of any commercially available burner of conventional construction that is suitable for use in a package boiler, is designed so as to be operative to effectuate therewith the introduction and thereafter subsequent combustion of the fuel, e.g., light oil, natural gas, heavy oil, etc., which the package boiler 10 is designed to have fired therewithin.
• the opening 58 in accordance with the illustrated embodiment of the package boiler 10 as depicted in Figures 2 and 8 of the drawing, the opening 58 is suitably provided within a windbox, the latter being generally denoted by the reference numeral 60 in both Figures 2 and 8 of the drawing.
• the windbox 60 is itself in turn suitably supported in mounted relation within the front wall 14 in the case of Figure 2 and within the front wall 14' in the case of Figure 8.
• modules, denoted by the reference numeral 64 of either ceramic fiber in the case of the ceramic fiber furnace front wall 14 or of heavy duty refractory in the case of the heavy duty refractory furnace front wall 14, are in accordance with the illustrated embodiment of the package boiler 10 of the present invention interposed between the outer surface of the refractory material 62 and on one hand the first tube 32 of the multiplicity of tubes 32 that collectively serve to comprise the side wall 18 and on the other hand the first tube 32 of the multiplicity of tubes 32 that collectively serve to comprise the partially extending wall 36.
• the modules 64 be they composed of ceramic fiber in the case of the ceramic fiber furnace front wall 14 or composed of heavy duty refractory in the case of the heavy duty refractory furnace front wall 14, are designed so as to be capable of being supported in mounted relation adjoining one another whereby the modules 64 comprise the major portion of the front wall 14.
• a plurality of members, each denoted by the reference numeral 66 in Figure 2 are preferably interspersed among the modules 64 at suitable locations relative thereto.
• modules 64 be they formed of ceramic fiber or of heavy duty refractory, constitute the major portion of the front wall 14 illustrated in
• FIG. 8 of the drawing the major portion of the front wall 14' illustrated in Figure 8 of the drawing is comprised of the multiplicity of tubes, which are denoted generally in Figure 8 by the reference numeral 72.
• adjoining ones of the multiplicity of tubes 72 are suitably interconnected by means of fins, the latter being denoted generally by the reference numeral 74 in Figure 8 such that collectively the multiplicity of tubes 72 and fins 74 combine to provide the front wall 14' with a gas-tight, wall-like front surface.
• FIG 8 of the drawing the multiplicity of tubes 72 and fins 74 have suitably formed therewithin the opening 58, which as has been described herein previously in connection with the description of the front wall 14 depicted in Figure 2 of the drawing is suitably dimensioned such that a burner, not shown in the interest of maintaining clarity of illustration in the drawing, may be supported in mounted relation therewithin.
• the opening 58 is suitably provided within a windbox 60, and the windbox 60 is itself in turn supported in mounted relation within the front wall 14' of Figure 8.
• the major portion of the rear wall 20 illustrated in Figure 7 of the drawing is comprised of the multiplicity of tubes, which are denoted generally in Figure 7 by the reference numeral 108.
• Adjoining ones of the multiplicity of tubes 108, as best understood with reference to Figure 7, are suitably interconnected by means of fins, the latter being denoted generally by the reference numeral 110 in Figure 7 such that collectively the multiplicity of tubes 108 and fins 110 combine to provide the rear wall 20 with a gas-tight, wall-like rear surface.
• the spacing of the fins 110 between adjacent tubes 108 of the rear wall 20, as in the case of the spacing of the fins 74 between adjacent tubes 72 of the fully water cooled furnace front wall 14', is made to be a maximum of one inch in order to thereby eliminate overheating and cracking problems associated with designs having wider tube spacing in the furnace area.
• the multiplicity of tubes 108 and fins 110 have suitably formed therewithin an opening, denoted generally in Figure 7 by the reference numeral 112.
• the opening 112 is suitably dimensioned such that in accordance with conventional industry practice a sootblower, denoted generally at 114 in Figure 7, may be suitably supported in mounted relation therewithin.
• the function of the sootblower 114 is to enable cleaning of the tubes 108 to be effected therewith.
• the rear wall 20 is shown to be provided with a single opening 112 and a single sootblower 114, it is to be understood that the rear wall 20 could, without departing from the essence of the present invention, be provided with additional openings 112 and additional sootblowers 114, with the additional sootblowers 114 being mounted one to an opening 112.
• sootblowers 114 could also be located in the front wall 14 or 14' and/or the side wall 16 and/or the top, i.e., roof, section 37 without departing from the essence of the present invention.
• the upper steam drum 40 extends the full length of the package boiler 10.
• the upper steam drum 40 includes a front end portion, denoted by the reference numeral 76, which projects outwardly of the front wall, be it the front wall 14 of Figure 2 or the front wall 14' of Figure 8, a rear end portion, denoted by the reference numeral 78, which projects outwardly of the rear wall 20, and a housing portion, denoted by the reference numeral 80, that extends between the front end portion 76 and the rear end portion 78.
• a normal water level, a high water level, a low water level and a low water cutoff are established for the upper steam drum 40.
• the normal water level is denoted by the dotted line identified in Figure 11 by the reference numeral 88
• the high water level is denoted by the dotted line identified in
• the high water level 90 preferably is established at a predetermined distance above the normal water level 88
• the low water level 92 preferably is established at a predetermined distance below the normal water level 88.
• the high water level 90 and the low water level 92 preferably are each spaced the same distance from the normal water level 88.
• the low water cutoff 94 preferably is established at a predetermined distance below the low water level 92.
• alarm means suitably associated in known fashion with the normal water level 88, the high water level 90, the low water level 92 and the low water cutoff 94 is a conventional form of alarm means.
• alarm means is designed to be operative to provide a suitable alarm, which may be in the form of an electrical, visual or audible signal, whenever the water level in the upper steam drum 40 is sensed to no longer be at the normal water level 88.
• an alarm means is designed to be operative to provide an alarm signal such that appropriate action may then in response to such alarm signal be initiated in order to thereby effect the return of the water Ievel within the upper steam drum 40 to the desired normal water Ievel 88.
• the signal generated from the low water cutoff 94 such signal would normally also effect, in accordance with conventional practice, a shutdown of the package boiler
• the upper steam drum is characterized particularly by the fact that improvements in the internals thereof, e.g., mesh dryer units 82, the perforated plate means 84 and the plate means 86, result in final polishing of the steam, which flows therethrough, to maximize dryness and also in a reduction in carry-over of boiler chemicals to the absolute minimum when used in conjunction with a proper feedwater conditioning program.
• the large diameter/capacity of the upper steam drum 40 enhances the ability of the package boiler 10, constructed in accordance with the present invention, to respond to typical feedwater flow fluctuations associated with transients that occur within the plant in which the package boiler 10 is being employed and other short term feed flow interruptions.
• the package boiler 10 constructed in accordance with the present invention is such that the package boiler 10 may be made to embody, if so desired, a superheater.
• a superheater generally designated by the reference numeral 96
• the superheater 96 when employed in the package boiler 10 of the present invention the superheater 96 preferably is suitably supported in mounted relation therewithin such as to be located in adjoining relation to the rear wall 20 of the package boiler 10.
• the location of the superheater 96 within the package boiler 10 of the present invention when the package boiler 10 is so equipped therewith is such that the superheater 96 essentially extends from the free end of the partially extending wall 36 to the rear wall 20.
• the tubes 32 of the package boiler 10 which would otherwise be present in the area within the package boiler 10 that the superheater 96 is intended to occupy, must of necessity obviously be moved in order to permit the superheater 96 to be located thereat.
• the superheater 96 is suitably supported on support piers, the latter being depicted at 98 in Figure 12.
• the tubes, denoted by the reference numeral 100, that collectively comprise the heat transfer surface of the superheater 96 are suitably interconnected at one end to the header, identified in Figure 12 by the reference numeral 102, and at the other end to the header, identified in Figure 12 by the reference numeral 104.
• the superheater 96 is suitably interconnected within the fluid flow path of the package boiler 10 of the present invention.
• the superheater 96 which is self- supporting and fully drainable when employed in the package boiler 10 of the present invention is located, as best understood with reference to Figure 12 of the drawing, behind a plurality of spaced tubes 32, which when arranged in this manner relative to the superheater 96 are commonly referred to by those in the industry as screen tubes.
• the burner that is designed to be mounted within the opening 58 that is suitably provided for this purpose in the front wall, be it the front wall 14 or the front wall 14', is operative to effect the combustion of fuel within the furnace portion 12 of the package boiler 10.
• the gases that are generated as a consequence of this combustion of fuel in the furnace portion 12 of the package boiler 10 flow along the following path in the course of traversing the interior of the package boiler 10. That is, these gases are made to flow along the length of the partially extending wall 36 of tubes 32 towards the rear wall 20 of the package boiler 10.
• the gases are made to flow parallel to the rear wall 20 in the direction of the side wall 16 such that the gases pass between the tubes 32 in the spaces provided therebetween. In doing so, the gases give up heat to the fluid flowing through the tubes 32.
• the gases After entering the area of the spaced tubes 32, the gases are made to flow parallel to the side wall 16 and eventually exit from the package boiler 10 through the gas outlet, denoted generally by the reference numeral 106 in Figure 1.
• gas outlet 106 is depicted as being located in the side wall 16, it is to be understood that the gas outlet 106 could also be located in the front wall 14 or 14', if such were to be desired by the purchaser of the package boiler 10, without departing from the essence of the present invention.
• a new and improved steam generator in the form of a package boiler that is of unitary construction.
• a new and improved package boiler of unitary construction that is characterized in that vis-a-vis prior art forms of steam generators it requires less auxiliary power, provides drier steam and reduces maintenance and field installation time, while yet being capable of being inexpensively tailored to meet the user's specific needs.
• a new and improved package boiler of unitary construction that is characterized in that it possesses the capability of producing steam at 20,000 to 180,000 pounds per hour, with design pressures to 1050 psig and design temperatures to 750 degrees F.
• a new and improved package boiler of unitary construction that is characterized in that it possesses the capability of being supplied in any one of three standard profiles, which collectively span a range of steam production at 20,000 to 180,000 pounds per hour as well as a range of design pressures to 1050 psig and a range of design temperatures to 750 degrees F.
• a new and improved package boiler of unitary construction that is characterized in that it possesses the capability whereby any one of the three standard profiles thereof can be customized as can the boiler length and the number of tubes wide in the boiler bank in order to thereby meet the user's specific pressure and temperature requirements.
• such a new and improved package boiler of unitary construction that is characterized in that it possesses the capability of embodying any one of the following options, i.e., rigidized ceramic fiber furnace front walls for light oil or natural gas firing, or heavy duty castable refractory front walls for heavy oil and other special fuels, or a fully water cooled front wall.
• a new and improved package boiler of unitary construction that is characterized in that it possesses the capability of embodying fin-welded furnace "D" tubes, baffle wall tubes and rear walls in order to thereby ensure a gas-tight combustion zone and uniform heat distribution to the tubes and fins, and with the fin spacing between adjacent furnace tubes being a maximum of one inch in order to thereby eliminate overheating and cracking problems associated with designs having wider tube spacing in the furnace area.
• a new and improved package boiler of unitary construction that is characterized in that it possesses the capability of embodying unheated downcomers in order to thereby assure positive circulation for faster transient response time and increased water Ievel stability.
• a new and improved package boiler of unitary construction that is characterized in that it possesses the capability of embodying improved steam drum internals in order to thereby provide final polishing of the steam to maximum dryness and reduce carryover of boiler chemicals to the absolute minimum when used in conjunction with a proper boiler feedwater conditioning program.
• a new and improved package boiler of unitary construction that is characterized in that it possesses the capability of embodying large/diameter capacity upper drums in order to thereby enhance response to normal feedwater flow fluctuations associated with plant transients and other short term feed flow interruptions.

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• Engineering & Computer Science (AREA)
• Physics & Mathematics (AREA)
• Thermal Sciences (AREA)
• Mechanical Engineering (AREA)
• General Engineering & Computer Science (AREA)
• Chemical & Material Sciences (AREA)
• Combustion & Propulsion (AREA)
• Control Of Steam Boilers And Waste-Gas Boilers (AREA)
• Furnace Housings, Linings, Walls, And Ceilings (AREA)
• Packaging Of Machine Parts And Wound Products (AREA)
• Packaging Of Annular Or Rod-Shaped Articles, Wearing Apparel, Cassettes, Or The Like (AREA)
• Turbine Rotor Nozzle Sealing (AREA)

Priority Applications (2)

Applications Claiming Priority (2)

Publications (1)

Family

ID=23843890

Family Applications (1)

Country Status (7)

Cited By (3)

Families Citing this family (2)

Citations (3)

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• 1996
  • 1996-05-23 CN CN96195772A patent/CN1127637C/zh not_active Expired - Fee Related
  • 1996-05-23 EP EP96914769A patent/EP0830544A1/en not_active Withdrawn
  • 1996-05-23 WO PCT/US1996/007600 patent/WO1996039594A1/en active IP Right Grant
  • 1996-05-23 TR TR97/01517T patent/TR199701517T1/xx unknown
  • 1996-05-23 AU AU58034/96A patent/AU723076B2/en not_active Ceased
  • 1996-05-23 CZ CZ19973866A patent/CZ293406B6/cs not_active IP Right Cessation
  • 1996-05-27 IN IN955CA1996 patent/IN189241B/en unknown

Patent Citations (3)

Non-Patent Citations (2)

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