US869701A - Fuel-economizer. - Google Patents

Fuel-economizer. Download PDF

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US869701A
US869701A US24899105A US1905248991A US869701A US 869701 A US869701 A US 869701A US 24899105 A US24899105 A US 24899105A US 1905248991 A US1905248991 A US 1905248991A US 869701 A US869701 A US 869701A
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tubes
headers
series
header
diameter
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US24899105A
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Ernest B Freeman
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BF Sturtevant Co
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BF Sturtevant Co
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    • FMECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F22STEAM GENERATION
    • F22DPREHEATING, OR ACCUMULATING PREHEATED, FEED-WATER FOR STEAM GENERATION; FEED-WATER SUPPLY FOR STEAM GENERATION; CONTROLLING WATER LEVEL FOR STEAM GENERATION; AUXILIARY DEVICES FOR PROMOTING WATER CIRCULATION WITHIN STEAM BOILERS
    • F22D1/00Feed-water heaters, i.e. economisers or like preheaters
    • F22D1/02Feed-water heaters, i.e. economisers or like preheaters with water tubes arranged in the boiler furnace, fire tubes, or flue ways

Definitions

  • the present invention relates to fuel economizers or feed Water heaters which utilize the heat oi the gases of combustion in heating the water.
  • the present invention relates to uel economizers which comprise upper and lower headers and a series oi vertical circulating tubes connecting each lower header with the corresponding upper header, the objects oi the invention being to iinprove the mechanical construction oi this type of fuel economizer and to insure a more thorough and complete circulation of the water through all portions oi the economizer.
  • the veitical tubes be arranged as closely together as the proper operation of the tube scrapers, by which the soot deposited on the tubes is removd will permit. 'lhisresults in the lower headers being placed closely together, and as the lower headers must have a sufficient lateral diameter to enable the vertical tubes to be connected thereto, the spaces beneath the bottom headers are comparatively narrow so that the soot removed from the tubes by the scrapers is not alquently only by removing a portion of the inclosing casing.
  • a feature of the present invention contemplates the provision of a construction oi vertical tubes and bottom headers whereby comparatively wide spaces are provided between the bottom headers to allow the soot removed from the tubes to fall freely into the pit beneath the headers and to enable the tube scrapers and their supporting and guiding plates to be readily replaced and adjusted from beneath the headers without substantially reducing the capacity of the tubes and headers or the surface of the tubes with which the heated gases come in contact.
  • lligure Vl is a vertical sectional view ol the economiser, the central portion of the vertical tubes and the casing being omitted and the upper and lower portions of the economizer being brought close together for convenience of illustration.
  • Fig. 2 is a plan view of a number of the lower headers in the position which they occupy in the ecouomizer, the lower ends of the vertical tubes connected therewith being shown in section.
  • Fig. S is a sectional view taken on the line 3--3 of Fig. 2 looking towards the left and Fig. -i is a similar view taken on the line 4-1 ot Fig. 2.
  • the economizer comprises a series of lower hcaders l, a corresponding series of upper headers 2, and a series of vertical pipes 3 connecting each lower header with its corresponding upper header.
  • the lower headers are connected at their forward ends by a manifold or wall box 1t by means of which the lower headers are placed in communication with each other.
  • the upper headers are provided at their rear ends with upwardly extending coupling chambers by means oi which the upper headers are placed in communication with each other.
  • the upper and lower headers are provided with sockets upon their under and upper sides respectively, in which sockets the upper and lower ends of the vertical tubes 3 are fitted, the construction and arrangement of the vei'tical tubes and headers, except as modified in accor'dance with the pr'esent invention, and all other' par'ts illustrated on the drawings, being the same as in the economizer illrrstr'ated and described in the patent to Burpee above referred to, to which r'efer'ence is made for a full disclosrri'e thereof.
  • a plurality of the ver'tical tubes ar'e substantially reduced in diameter' at their lower' ends, the tribes being preferably, however, of the saine dia-meter for the greater' portion of their length, so that the r'edriction in the diameter of the lower' ends of the tubes does not substantially diminish their' capacity or the surface presented to the heated gases.
  • the upper ends of the vei'tical tubes ar'e preferably of the same or somewhat greater diameter' than the main portions of the tubes in or'der to facilitate assembling the tubes and headers as described in the patent to Burpee No. 44l,392,dated November' 25, 1890. It is also believed that this construction irnpr'oves the circulation of water through the vertical tubes.
  • the bottom headers are correspondingly reduced in their lateral diameter' at the points of connection therewith of the reduced lower ends of the vertical tubes, as is clearly shown in Figs. 2 and 4.
  • the r'edriction in the lateral diameter' of the bottom headers at these points permits a i'edriction in the latei'al diameter of the lower headers throughout the portions with which the vertical tubes ai'e connected so that comparatively wide spaces ai'e left between the bottom headers through which the soot removed from the tubes by the scrapers can fall freely, and through which a workman can insert his hand or arm and readily re-adjrist or replace a broken or displaced scraper or scraper guiding or supporting plate.
  • the lower lreader's are preferably cir'cular' in cross section at their forward ends and in or'der that the capacity of the lower headers may not be substantially diminished the portions to which the reduced lower ends of the vertical tubes ai'e connected ai'e preferably substantially rectangular' in cross section, as indicated in Fig. 4.
  • the present invention contemplates reducing the lower ends of any number of the vertical tubes connecting 'a lower' and an upper header.
  • the fr'ont tube of each series of tubes which connect arr upper and a lower header is of substantially the saine diameter throughout and the i'cmaining tubes ar'e substantially r'edriced in diameter at their lower ends, as thereby the circulation of water through the economiZer is improved, as will be hereinafter explained.
  • the economiZer'"illustrated in the drawings as embodying the present invention can be fed with either hot or cold water', the water being fed into the bottom of the econorniZer' when hot water is used and being fed into the top of the econornizer when cold water is used, in accordance with the usual practice.
  • cold water is fed into the econornizer it entei's at the rear ends of a number of upper headers and on account of the constr'icted openings at the lower' ends of the ver'tical tubes tends to pass forward into the headers and enter a number of the vertical tubes instead of passing directly down the vertical tubes at the r'ear' oi the econornizer.
  • the reduction in the diameter of the vertical tubes at their' lower' ends also improves the circulation when hot water is fed to the economizer.
  • the precise manner' in which the water circulates has not as yet been accurately determined but it is believed that the cir'- crilation is substantially as followsz-Vhen hot water is fed to the cconomizer in large quantities it enter's fr'orn the wall box 4 into a number oi lower' headers.
  • the greater portion of the water entering a header passes rip the fr'ont tube of the sei'ies connecting the header' with its corresponding upper' header.
  • the present invention has been illustrated arid described as applied to the fuel econornizer disclosed in the patent to Burpee, No. 729,273. It is to be understood, however, the invention is not limited to such application but may be embodied in any fuel economizer comprising upper and lower headers and vertical circulating tubes.
  • a fuel econornizer having, in combination, a series or lower' headers, a series of upper' headers, and a series of vertical circulating tribes connecting each lower' header' with an upper' header', :i plurality of said vertical tubes being substantially reduced in diameter' at their lower' ends and said lower headers being correspondingly reduced in their' lateral diameter' :it the points of connection therewith of said vertical tribes, substantially as described.
  • a ⁇ fuel economiser having, in combination, a series or' lower' headers, a seriesof ripper' headers, and a ser'ies of vertical circulating tribes connecting each lower' header' with an ripper' header', a plurality of said tubes being of the same diameter' for' the greater portion of their length and being substantially reduced in diameter' at their' lower ends and said lower' headers being correspondingly reduced in their lateral diameter' at the points of connection therewith of the vertical tribes, substantially as described.
  • a fuel econoniizer having', in combination, a series of lower' headers provided with sockets on their ripper sides, :r corresponding series of ripper' headers provided with sockets upon their' rinder' sides, and a series of vertical circulating tribes connecting ⁇ each lower' header' with :in ripper' header' and iitted at their' upper and lower' ends irr'said sockets.
  • la plurality of said tribes being substantially reduced in diameter' at their' lower ends and said lower' header-s being correspondingly reduced in their' lateral diameter' at the points of connection therewith of the vertical tubes. substantially as described.
  • a fuel econoniizer having, in combination, a series of lower' headers in communication with each other' at their' forward ends, a corresponding series of ripper' headers in communication with each other' at their rear' ends, and a series of vertical circulating' tubes connectingl each lower' header' with an ripper' header', the front tribe of said ser'ies beingl of substantially the saine diameter throughout and the remaining tubes 0t ⁇ said series being;l substautially re ⁇ quizd in diameter at their lower ends. substantially as (le scribed.
  • a t'uel economizer having, in combination, a series of lower headers in connnunication with each other at their forward ends,.a corresponding;- series ot' upper headers in communication with each other at their r Ear ends, and a series 0f vertical circulating tubes connecting each lower header with an upper header, the t'ront tube ot' said series of vertical tubes being' of substantially the same diameter throughout, the remainder of said tubes beine substantially reduced in diameter' at their lower ends and said lower headers heine; correspondingly reduced in their lateral diameter at the points ot' connection therewith ot' the ieduced lower ends 0t ⁇ said vertical tubes, substantially as described.
  • a t ⁇ uel economizer having', in combination, a series ot' lower headers provided with sockets on their upper sides, a corresponding series ot upper headers provided with sockets upon their under sides. and a series of vertical circulating tubes connectingl each lower header with an upper header and titted at their upper and lower ends in said sockets, a plurality ot said tubes beineot the same diameter for the greater portion of their length and being substantially reduced in diameter at' their lower ends, substantially as described.
  • a t'uel cconomizer having', in combination, a series ot upper headers, a series oi lower headers and a series of vertical circulatingv tubes connecting each upper header with a lower header, a plurality ot said tubes being ot? substantially less diameter at their lower than at their upper ends. and one or more ot' said tubes bein.: ot' suhstantially tht ⁇ same diameter throughout, substantially as de ribed S.
  • a t'uel economizer having, in combination, a series of upper headers.

Description

No. 869,'701. PATENTED OCT. 29. 1907 E. B. FREEMAN.
FUEL ECONOMIZBR.
APPLICATION FILED MAR. a, 1905.
No. 869,701. 'PATENTED 00T. 29. 1907.
E.` E. FREEMAN. FUEL EGONOMIZEE.
APPLIOATION FILED MAR. 3. 1905.
' 2 SHEETS-SHEET 2.
m: Nomus :leren: co.. wAs'mNsroN, vA z:v
UNITED sTATEs 'PATENT oEEioE.
ERNEST B. FREEMAN, OF DEDHAM, MASSACI'IUSE'1"I`S, ASSIGNOR TOB. F. STURTEVANT COMPANY, OF BOSTON, MASSACHUSETTS, A CORPORATION OFMASSACI-IUSETTS.
FUEL-E CONOMIZER.
Specification of Letters Patent.
Patented Oct. 29, 1907.
Application filed March 8,1905. Serial No. 248.991.
To all lwhom it may concer/n:
Be it known that I, ERNEST B. FREEMAN, a citizen of the United States, residing at Dedham, in the county of Norfolk and State of Massachusetts, have invented certain new and useful Improvements in lhiel-llconomizers; and I do hereby declare the following to be a full, clear, and eXact description of the invention. such as will enable others skilled in theI art to which it appertains to make and use the saine.
The present invention relates to fuel economizers or feed Water heaters which utilize the heat oi the gases of combustion in heating the water.
More particularly the present invention relates to uel economizers which comprise upper and lower headers and a series oi vertical circulating tubes connecting each lower header with the corresponding upper header, the objects oi the invention being to iinprove the mechanical construction oi this type of fuel economizer and to insure a more thorough and complete circulation of the water through all portions oi the economizer.
In the type oi economiser above referred to it is desirable that the veitical tubes be arranged as closely together as the proper operation of the tube scrapers, by which the soot deposited on the tubes is removd will permit. 'lhisresults in the lower headers being placed closely together, and as the lower headers must have a sufficient lateral diameter to enable the vertical tubes to be connected thereto, the spaces beneath the bottom headers are comparatively narrow so that the soot removed from the tubes by the scrapers is not alquently only by removing a portion of the inclosing casing.
A feature of the present invention contemplates the provision of a construction oi vertical tubes and bottom headers whereby comparatively wide spaces are provided between the bottom headers to allow the soot removed from the tubes to fall freely into the pit beneath the headers and to enable the tube scrapers and their supporting and guiding plates to be readily replaced and adjusted from beneath the headers without substantially reducing the capacity of the tubes and headers or the surface of the tubes with which the heated gases come in contact.
In fuel economizers of the type referred to there is liability of the water admitted to the economizer passing to the outlet pipe without circulating properly through the vertical tubes, and a feature of the present when the economizer is fed with cold water, moisture in the form of a corrosive acid is condensed upon the tubes from the gases of combustion` and collects at the lower ends of the tubes. The corroding of the tubes at their lower ends by this acid gives considerable trouble in actual practice.` as the tubes are weakened and frequently break at this point. The present invention in addition to securing a proper ci rculation of the water admitted to the cconomizer also substantially prevents the condensation of moisture from -the gases upon the tubes or the sweating of the tubes.
The various features of the present invention will be clearly understood from an inspection of the accompnnying drawings, in which is illustrated a fuel economiser embodying the same in their preferred form.
Referring to the drawings, lligure Vl isa vertical sectional view ol the economiser, the central portion of the vertical tubes and the casing being omitted and the upper and lower portions of the economizer being brought close together for convenience of illustration. Fig. 2 is a plan view of a number of the lower headers in the position which they occupy in the ecouomizer, the lower ends of the vertical tubes connected therewith being shown in section. Fig. S is a sectional view taken on the line 3--3 of Fig. 2 looking towards the left and Fig. -i is a similar view taken on the line 4-1 ot Fig. 2.
'lhe economixer illustrated in the dr-.uvings is similar to the economiser illustrated and described in the patent to George II. Burpee, No. 729,272, dated May 26, 1903, the various parts, except as modified in accordance with the present invention, being constructed and arranged as disclosed in said patent. The economizer comprises a series of lower hcaders l, a corresponding series of upper headers 2, and a series of vertical pipes 3 connecting each lower header with its corresponding upper header. The lower headers are connected at their forward ends by a manifold or wall box 1t by means of which the lower headers are placed in communication with each other. The upper headers are provided at their rear ends with upwardly extending coupling chambers by means oi which the upper headers are placed in communication with each other. The upper and lower headers are provided with sockets upon their under and upper sides respectively, in which sockets the upper and lower ends of the vertical tubes 3 are fitted, the construction and arrangement of the vei'tical tubes and headers, except as modified in accor'dance with the pr'esent invention, and all other' par'ts illustrated on the drawings, being the same as in the economizer illrrstr'ated and described in the patent to Burpee above referred to, to which r'efer'ence is made for a full disclosrri'e thereof.
In accordance with the present invention a plurality of the ver'tical tubes ar'e substantially reduced in diameter' at their lower' ends, the tribes being preferably, however, of the saine dia-meter for the greater' portion of their length, so that the r'edriction in the diameter of the lower' ends of the tubes does not substantially diminish their' capacity or the surface presented to the heated gases. The upper ends of the vei'tical tubes ar'e preferably of the same or somewhat greater diameter' than the main portions of the tubes in or'der to facilitate assembling the tubes and headers as described in the patent to Burpee No. 44l,392,dated November' 25, 1890. It is also believed that this construction irnpr'oves the circulation of water through the vertical tubes. Also in accordance with the present invention the bottom headers are correspondingly reduced in their lateral diameter' at the points of connection therewith of the reduced lower ends of the vertical tubes, as is clearly shown in Figs. 2 and 4. The r'edriction in the lateral diameter' of the bottom headers at these points permits a i'edriction in the latei'al diameter of the lower headers throughout the portions with which the vertical tubes ai'e connected so that comparatively wide spaces ai'e left between the bottom headers through which the soot removed from the tubes by the scrapers can fall freely, and through which a workman can insert his hand or arm and readily re-adjrist or replace a broken or displaced scraper or scraper guiding or supporting plate. The lower lreader's are preferably cir'cular' in cross section at their forward ends and in or'der that the capacity of the lower headers may not be substantially diminished the portions to which the reduced lower ends of the vertical tubes ai'e connected ai'e preferably substantially rectangular' in cross section, as indicated in Fig. 4.
The present invention contemplates reducing the lower ends of any number of the vertical tubes connecting 'a lower' and an upper header. In the pr'efer'r'ed embodiment of the invention, however, the fr'ont tube of each series of tubes which connect arr upper and a lower header is of substantially the saine diameter throughout and the i'cmaining tubes ar'e substantially r'edriced in diameter at their lower ends, as thereby the circulation of water through the economiZer is improved, as will be hereinafter explained.
The economiZer'"illustrated in the drawings as embodying the present invention can be fed with either hot or cold water', the water being fed into the bottom of the econorniZer' when hot water is used and being fed into the top of the econornizer when cold water is used, in accordance with the usual practice. When cold water is fed into the econornizer it entei's at the rear ends of a number of upper headers and on account of the constr'icted openings at the lower' ends of the ver'tical tubes tends to pass forward into the headers and enter a number of the vertical tubes instead of passing directly down the vertical tubes at the r'ear' oi the econornizer. The cold water slowly settles in the tubes and before it reaches the bottom headers is heated to a sufficient degree to prevent sweating of the tribes. The reduction in the diameter of the tubes at their lower' ends thris improves the circulation of the water when cold water is fed to the economizer and also prevents the sweating of the tubes and the consequent corr'oding of the tubes at their' lower ends.
The reduction in the diameter of the vertical tubes at their' lower' ends also improves the circulation when hot water is fed to the economizer. The precise manner' in which the water circulates has not as yet been accurately determined but it is believed that the cir'- crilation is substantially as followsz-Vhen hot water is fed to the cconomizer in large quantities it enter's fr'orn the wall box 4 into a number oi lower' headers. The greater portion of the water entering a header passes rip the fr'ont tube of the sei'ies connecting the header' with its corresponding upper' header. The water their passes rearwardly along the upper' header' and passes down one or rnor'e of the vertical tubes' which are reduced in diameter at their lower ends, thris agitating the Water' in the vertical tubes to a considerable extent, and tending to bring every particle of the water in contact with the sides of the tubes. When hot water is fed to the economizer in small quantities a portion of the water goes up the front tubes as before but as the circulation is slow some of the water passes along the lower' headers and goes up the tubes which are reduced in diameter' at their lower ends.
The present invention has been illustrated arid described as applied to the fuel econornizer disclosed in the patent to Burpee, No. 729,273. It is to be understood, however, the invention is not limited to such application but may be embodied in any fuel economizer comprising upper and lower headers and vertical circulating tubes.
Theinvention having been thus described, what is claimed is l. A fuel econornizer, having, in combination, a series or lower' headers, a series of upper' headers, and a series of vertical circulating tribes connecting each lower' header' with an upper' header', :i plurality of said vertical tubes being substantially reduced in diameter' at their lower' ends and said lower headers being correspondingly reduced in their' lateral diameter' :it the points of connection therewith of said vertical tribes, substantially as described.
2. A `fuel economiser, having, in combination, a series or' lower' headers, a seriesof ripper' headers, and a ser'ies of vertical circulating tribes connecting each lower' header' with an ripper' header', a plurality of said tubes being of the same diameter' for' the greater portion of their length and being substantially reduced in diameter' at their' lower ends and said lower' headers being correspondingly reduced in their lateral diameter' at the points of connection therewith of the vertical tribes, substantially as described.
A fuel econoniizer, having', in combination, a series of lower' headers provided with sockets on their ripper sides, :r corresponding series of ripper' headers provided with sockets upon their' rinder' sides, and a series of vertical circulating tribes connecting` each lower' header' with :in ripper' header' and iitted at their' upper and lower' ends irr'said sockets. la plurality of said tribes being substantially reduced in diameter' at their' lower ends and said lower' header-s being correspondingly reduced in their' lateral diameter' at the points of connection therewith of the vertical tubes. substantially as described.
l. A fuel econoniizer, having, in combination, a series of lower' headers in communication with each other' at their' forward ends, a corresponding series of ripper' headers in communication with each other' at their rear' ends, and a series of vertical circulating' tubes connectingl each lower' header' with an ripper' header', the front tribe of said ser'ies beingl of substantially the saine diameter throughout and the remaining tubes 0t` said series being;l substautially re` duced in diameter at their lower ends. substantially as (le scribed.
5. A t'uel economizer, having, in combination, a series of lower headers in connnunication with each other at their forward ends,.a corresponding;- series ot' upper headers in communication with each other at their r Ear ends, and a series 0f vertical circulating tubes connecting each lower header with an upper header, the t'ront tube ot' said series of vertical tubes being' of substantially the same diameter throughout, the remainder of said tubes beine substantially reduced in diameter' at their lower ends and said lower headers heine; correspondingly reduced in their lateral diameter at the points ot' connection therewith ot' the ieduced lower ends 0t` said vertical tubes, substantially as described.
ti. A t`uel economizer, having', in combination, a series ot' lower headers provided with sockets on their upper sides, a corresponding series ot upper headers provided with sockets upon their under sides. and a series of vertical circulating tubes connectingl each lower header with an upper header and titted at their upper and lower ends in said sockets, a plurality ot said tubes beineot the same diameter for the greater portion of their length and being substantially reduced in diameter at' their lower ends, substantially as described.
7. A t'uel cconomizer, having', in combination, a series ot upper headers, a series oi lower headers and a series of vertical circulatingv tubes connecting each upper header with a lower header, a plurality ot said tubes being ot? substantially less diameter at their lower than at their upper ends. and one or more ot' said tubes bein.: ot' suhstantially tht` same diameter throughout, substantially as de ribed S. A t'uel economizer, having, in combination, a series of upper headers. a series ot' lower heade' and a series of vertical circulating tubes connecting e: ch upper header with a lower header, a plurality ot said tubes being of the same diameter l'or the .a'reatei' portion of their length and being.,y substantially reduced in diameter at their lower ends, substantially as described.
In testimony whereot' I atlix my signature. in presence of two \\'itnesses.
ERNEST B. FREEMAN.
Witnesses Flinn O. Fisn.
llonACn VAN Ilvnnnx.
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