USRE10923E - prall - Google Patents

Description

. 2 Sheets-Sheet 1. W. E. PRALL.

Assignor, by mesne assignments, to the NATIONAL HEATING COMPANY. MEANS FOR SUPPLYING HEAT AND STEAM-ORWATER POWER TO wi l .oea, x fl at V 8 I a,

' 93) 5 aHy/neq 5 g '2 Sheets-Sheet 2.

W. E. PRALL. 'Assignor, by mesne assignments, to the NATIONAL HEATING COMPANY. MEANS FOR SUPPLYING HEAT AND STEAM 0R WATER POWER TO CITIES, TOWNS, &c.

Reissued Apr.

PATENT OFFICE.

WILLIAM IRALL, or WASHINGTON, msrmor OF COLUMBIA, ASSIGNOR, :Y MESNE ASSIGNMENTS, T run NATIOXAL HEATING COMPANY, or

NEW' YORK, N. Y.

MEANS FOR SUPPLYING HEAT AND STEAM 0R WATER POWER TO CITIES, TOWNS, dc.

SPECIFICATION forming part of Reisaued Letters Patent No. 10.923, dated April 17, 1888.

Original No. 379,283,]danul Mar-c1113, 1888. Application for reissue filed March 27, 1888. Serial No. 268,726. Patented in Eng hm'd Jnly .23, 1879, No. 9,987, and in Germany January 37, 1880, No. 13,522.).

To all whom it may concern:

le it known that 1, W LLIAM .E. PRALL, a citizen of the United States, and a resident of Washington, in the District; of Columbia, have invented certain new and useful Improved Means for Supplying Heat and Steam or Vater Power to Large Districts of Buildings in Cities and Towns, (for which I have obtained a patent in Great Britain, N0. 2,987, dated [0 July 23, 1879; also in Germany, No. 13,525,

dated January 27, 1880,) of which the following .is a \eciiication.

This invention relates to a novel means of conveying hcatl'or the purpose of warming I5 large districts of buildings in cities and towns and tothe manner of utilizing and distributing the same from one common source of supply, and embodies a safe, economical, convenient, and healthful system of delivering and controlling the heat in each and every building and compartment therein, and of supplying motive power for, propelling street cars, stationary engines, and for other purposes.

Figure l is a partsectional vicwof a'heating tank or boiler and prcheater or water-heater, alsoofahotwater-oi rculating main and a building fitted up with radiators connected with an apparatus for converting the hot water when taken from the main pipe into steam, and traps for returning the water of condensation to the circulating-main. Fig. 2 shows a plan view of the heaters and circulating-pumps, together with a view of the pipes conveying hotwater through different streets and pipes for return- 5 ing the water of condensation, and a pump for' forcing the same into a preheatcr, and thence directly into theheater from which it"was previously taken. Fig. 3 shows three modificatimes of the apparatus for taking the hot water 0 from the main and utilizing the same for heating buildings, as well as arrangements for metering the same. Figs. 4, 5, 6, 7, S, and 9 are detail drawings of a pressure-regulatil'ig valve, temperature and balance valve for controlling the exhaust-water from. the radiators, and means for draining the circulating-pipes, and

an apparatus for measuring steam. In Fig. 1, A. represents a hot-water tank or heater, and should be of sufficient capacity to so furnish all the hot water that would be required for supplying heat to the district reached by the circulation pipe or main 0, said pipe being connected thereto at or near the bottom, certainly below the water-line. The heater is provided with a constant supply of water by means ofa pumping-engine from any convenient source, in such'quantities as are-needed to keep up the waste from the main pipe, which may be drawn from it for any pnrposewhatever. The power for driving the pumping-engine may be taken from the steam generated in the water-heater, or it may be taken from any other boiler erected for that purpose. I

-It is evident that there may be several of the water-heaters em ployod for the purpose of, supplying water for circulation, and they may all be connected, or they maybe separated by means of cocks placed in the connecting-pipes, so that one or more of them may be used independent of the others.

In the practical operation of this invention the water-heaters should be located in a suitable building convenient to the district to be supplied with heat, and the cireulating-pipe 0 connected with the force-pump B,said pump being also connected with C, which is, in fact, the same from its connection with the heater A, extending through the force or circulatingpump B, and from thence through one street and returning through another, as represented,

and terminating again in the heater, the purpose of the force-pump B being only that of circulating the hot water, taking it from the heater under pressure, and returning it again for the purpose of reheating, and the pump will be kept operating-with suflicient rapidity to cause theflow of water to be rapid enough to convey heat without much reduction of temperature along-the entire length of the pipe.

Other means may be employed to circulate the water through the pipes-as, for instance,

the two ends may be connected with different heatersihaving a difl'erent pressure, and thus the hot water may be forced from the onehav 1 ing the greater pressure through thq,pipe connectingit with-the heaterof less pressure.-

It is evident that variousmeaus may be employed for circulating water, hence I do not confine myself to any particular manner, and in some places where the amount drawn from the pipe was sufficiently great the flow m'ight be enough to keep the temperature high at-the farthest end without the necessity of returning it to the heater, and in that case no returnpipe or force-pump would be required; but the evident advantage of circulating the water is so apparent as to make the adoption of a single pipe only a possibility.

The street-main is to be covered with some non-conducting substance to prevent;as' much as possible,the radiation of the heat therefrom, andis also provided with expansion" and contraction joints to allow for the movement of the main pipe longitudinally. The manifold advantages of thus conveying heat great distances will be easily comprehended, because as the weight or body of a cubic foot of water (or any given quantity) is at the boiling or steamgenerating point seventeen hundred (1,700)'times as great as the steam thrown off at that temperature, it follows that it contains a far greater number ofunits of heat. Thus it will be seen that a much larger amount of heat may be delivered through a pipe a great distance without loss from condensation than could be effected by means of .steam, and the hot water may by this process be converted into steam or otherwise used for the purpose of heating buildings at the point where required and overcome the greatdiflicnlty which has heretofore prevented the heating of buildings located at a distance from the generator, at the same time afl'ording a much more con-' venient and economical means of heating than by separatefires and generatorslocated in each building, and also avoiding much risk from danger by fire. v

In Fig. 1, A represents a hot-water tank or heater,which should be of sufficient capacity to furnish all the hot water that would be required for supplying heat to the district reached by the circulating pipe or main G, said pipe being connected thereto at or near the bottom, either directly or. indirectly, via the preheater A, as shown by the pipe-connections and the arrows. B represents a circulating-pump, which is connected with the pipe 0 at some point between the connections of the two ends of the same with the heater A, the nnrpose of which is to cause the hot water to move through the said pipe and be returned to the heater again, and it may be placed at either end of the'circulating-pipe.

The power for running it maybe derived from any source whatever. The pump B maybe placed in the pipe connecting the preheatingtank with the main heater, and as it would take the water from the preheater the hot water would be forced from the heater of greater pressure through thecirculating-pipes into the preheater or heater of less pressure, and thus circulation would be maintained in the pipe,which pipe may extend for a considerable distance on the street and return again to the heater. I have shown in this figure one manner ofrconveying the hot water to a building and utilizing the same for heating purposes. In th'e illustration, D represents a tank connected with the hot-water'pipe C by means of branch pipes D' and D, said pipes being arranged to unite the tank D with the circulatingpipe G at the same point, either very near together, as shown by pipes D and D, or a greater distance apart, by attaching one to the outflow-ing end of the pipe 0 and the other to the inflowing end of the same, as shown by pipes D and D". X represents an other tank placed within the tank D, leaving a space between the two. F is-the pressureregulating valve in the pipe connecting.- the tanks D and X. E is a pipe connecting with theinterior tank; X, and extends to the radiators F in' the different parts of the house. F is the. condensed-water pipe, extending from the bottom of the radiators to the dischargevalve'E', and thence to the circulating-pipe O. E represents a meter of any kindconnected with the discharge F. C represents a cock or valve,which may be used to increase or-diminish the size of the pipe 0, for the purpose of controllingt he pressure and the rapidity of the circulation in said pipe. If the heater A be now filledwith water and by means of the fire in the furnace is heated to a high degreefor example, say 332 Fahrenheit, which would give a pressure of abont'one hundred pounds tothe square inch, 'andbe kept at that point,

which would be one hundred and twenty degrees above the steam generating point-and if the connections at both ends of the circulating water-mains be opened, the pressure upon them and the-water therein will be the same as upon the-water inthe heater and preheater, and if the force-pump be put in motion it will cause the water to be forced through the pipe by taking it 'l'rom the heater and by discharging it again into the same through the returmpipe and through the prebeater. The result will be to soon establish a temperature of aboutthe same degree to the water in the main pipe its entire length as that in the heater. It, now, the

cocks in the pipes'D' and D' be opened, the

hot water under pressure will flow from the main pipe 0 into the outside tank, D, and surround the inner tank, and if the regulatingvalve F be constructed to establish a ratio of difl'erence in pressure that may be desirable the water from between the tanks D and X will flow intoX-through the valve and connecting-pipe F; but as soon as a small quantity has entered the tank X the reduction of pressure established by the differential valve will cause the hot water so admitted to be converted into steam, as it contains-many degrees of heat above the steam generating point, as

before mentioned. As soon as-the quantity of water thus admitted, however, has'been evaporated into steam the space in the tank Xwill be filled under pressure, which will act upon the differential valve F and close it and prevent the further admission of hot water. The

steam from tank X will force itswav through to E, and thence to the pipe again.

pipe E into the difl'erent radiators connected thereto and heat the same"; but the cold air surrounding them conveys away the heat, and the steam therein will be condensed, and thus 5 the amount of water admitted into tank X will be converted into steam and conducted to the radiators. The condensed water, therefore, will be conducted through the pipe F and the temperature discharge-valve E" to the meter As soon as condensation has reduced the steam-pressure snflicieutly in tank X and con nectingpipes and radiators, more hot water will be admitted through the difi'erential valve F into tank X,

r5 and thus the supply' will be kept constant.

The hot water admitted into tank X will not be converted into steam by means of its own specific heat, and hence the purpose of surrounding the converting-chamber X with the hot water in tank D, the heat. of which will cause all the water admitted into .tank X to be evaporated. The purposeof connecting pipes l) and D" is to unite tank D with the main pipe 0, and thus produce circulation, for it will be seen that as the water in said tank transmits its heat into the water which is ad mitted into the interior tank, X, its tetnper-' ature thereby will be proportionately lowered, and hence heavier, and circulation will thus be established between the hot-water pipe 0 and the tank D through pipes D and D, and" by means of this circulation at temperature will be maintained in said tank nearly the same asin the pipe 0. Il'the cock in the circulating pipe 5 C be partially closed and the pump B is kept in operation with snfii-cient rapidity to remove the water from the end of pipe 0 faster than it is permitted to flow through the contracted opening in the pipe at the cock 0, the result 4.0 would be to make the pressure less in the return end of the circulating-pipe O, and thus increase the rapidity of circulation through the pipes D andl), as well as from the condense-water pipe; or it the circulating-pump is placed at the outilowing end of the circulating-pipe (J the effect would be to increase the pressure in that end above that'of the intlowing end, which would have the same effect to increase the circulationthrongh the branch pipes connected thereto.

The manner of utilizing to the best possible advantage allthe heat in the coal in preheating the water before it is admitted into the main-heater is accomplished, as shown in Fig.

1, by placing the preheater above the main heater i-nsuch a manner that the heat will pass through the preheater after passing through the main heater. In this manner all the water from the return-pipe, which is of a lower temperature than that inthe heater A, will be caused to pass through the preheater.

In Fig. 2 l have shown .a plan for circulati'ng hot water around several blocks of buildings and means for controlling the flow in each V and every section, and also asystem of returnpipes connected. with the main hot-waterpi'pes by the connecting-pipes from the radiators,

and connections between the hot-water or supply pipes and the return-pipes may be made at the connections K at the junction of the streets, if desired. I have also shown in this figure a double-cylindcred pump-one used for circulating the hot water and the other for taking the. return-water from the pipes and .forcing it into the heater or preheater. In

this figure, 1-1 designates the supply-pipe and K the return-pipe, and the circulation is as indicated by the arrows. It is evident that by means of cocks or valves at the connections K the circulation in any of the cross-pipes may be cut off or controlled. L is the pipe which connects the supply-pipe .ot' the street with the building, and M the pipe which returns the water to the'rctnrn-pipe of the street, by which it is rcconveyed to the heater. It is evident that very little water would be wasted from the pipes, except that drawn off for domestic purposes, as all the condensed water would be returned for reheating, and the amount so drawn from the pipes the pump H will supply from any convenient source. It is evident that a force-pump may be employed to cause circulation in the return-pipe, and that the pump B may be placed at either end of the supplypipe.

In Fig. 3 l have shown several other modes of arranging the pipes and connections for conveying the hot water from the mains to the radiators and for returning the same after the heat has been cxtractcd'aud utilized in warming buildings and propelling engines, &c., and means for preventing the radiation' of heat from the pip s. In this figure, A represents the heating-tank, B the circulating-pump, and O N the hot-water main and return-water main; P, the drain-pipe. In this building-- the first building-water is admitted from the main through the pipe Oiuto the regulatingvalve 0. The steam thrown oil by the reduction of pressure by means of this valve is conveyed to the radiators connected thereto by means of pi pcs. The water admitted to the evaporator through the regulating-valve, which is not converted into steam, is conveyed through the hot-water coil connected therewith, and thence throu h the discharge valve or trap O"into the return-pipe N, which may be-one continuous circulating-main, as shown in Fig. 1, or it maybe a separate pipe connected with the'supply-main. only by means of the branch pipes, as shown in Fig. 2, these branch pipes being also connected with the radiators, and the return-water maybe taken therefrom by the suctioupninp andjorced into the preheater, and thence ditto the main heater, as shown in Fig. 2. The meter 0' will register the alnountoiwaterforcedthrough the pipe 0 and as the trap O is made toprevent the discharge of the condensed water only after it has had its temperature reduced to a. certain degree it becomes art easy matter of calculation to determine the amount of heat consumed. I have IIO ' ply-pipe, as shown, and at all times when the the hose may be easily extinguished.

system is in operation any fire within reach of In the second building of this figure the apparatus is the same, except the air conveyed into the rooms is admitted to the cabinet containing the coil, and after being heated is delivered through the fines extending therefrom into the various apartments. In the third buildingof this figure is shown an arrangement of the pipes and radiators ina manner to utilize. the hot water under full pressure. This plan has some advantages over the use of steam for heating purposes, in that it can be controlled by means of cocks or valves in such a manner as to keep the temperature of the radiators at any desired degree, while with steam it 'must either' be at its full heat or entirely out OK. All who have used steam have been inconvenienced by this lack of control of the heat. Then, again, the noise occasioned by the condensation of steam is entirely avoided when hot water is used directly in radiators. I have also shown in this figure anengine whieh'ean' be run for power directly withv hot water, and

by exhausting into the returnpipe be quite as economictland operative as when run by steam, as all condensed water will beconveyed back tothe heater. There is no difficulty in working water at'a high temperature in an engine properly constructed and arranged to exhaust in this manner, provided the cut-off is arranged to work very expansively aiid at a low pressure and finely wire-drawn or dissipated. The meter will determine the amount of water consumed, as in any other operation. In some of theillustrations I have shown the meter in position to measure the condensed water from the radiators. This plan, however, is not considered very practical as a means of determining with any degree of accuracy the amount of heat consumed, as themany accidental leaks, to say nothing of those pur-' po'sely left in that condition, would easily allow of a very great discrepancy, asone cubic foot of condensed water would rep resent nearly. a thousand cubic feet" of steam; hence great opportunity would be aiiorded to practice im-' position by means of the many cocks, valves, and joints in and about the house. The only accurate'way when steam is used ina build; ing is to meter the water first before it has entered any of the pipes and radiators conneeted therewith, t.

Fig. 4 represents a pressureregulating valve. 7 I t is constructed by fitting a movable plug, B, into the cylinder or barrel R, the plug having a recessturned orv cut in it about the center, which communicates by means of openings with the tank R, to which the case B is fastened. The plug has a stem extending outward through the cap of the cylinder It, which carries a weight, R. In the practical operation of this valve,'the pressure-pipe B being opened, the hot water is admitted.

from the main pipe through the branch pipe and meter connected therewith, as shown in the first and second buildings of Fig. 3. The

communication being opened, the hot water will pass freely into the tank or convertingchamber R; but upon entering the said tank the. pressure will be immediatelyrelieved and steam will be generated, the pressure of which willact upon the plug R, and as soon as the pressure has exceeded that of the weight It the plug will be thrown'up and the inlet-port from the pipe R will be cut off and the further admission of hot water will be prevented; but as condensation is constantly going on in the radiatorswhich connect with the converting-chamber R, the pressure will soon be so far reduced therein that the weight R will be greater than the sustaining force of the steam on the face of the plug R, and it will begin to descend again. This movement will expose the inlet-port and a further admission of hot water will be permitted, which will again be converted into steam, and in thismanner a constant and nearly-equal pressure will be maintained in the tank or converting-chamber R and radiators connected therewith, irre' spective of the pressu in the main or hot water pipe.

In Fig. 9 I have shown a detached view of an apparatus to be used in converting the hot water into steam for running engines, which is designed for-use at such times and places where steam only is required for power. V. represents a converting-tank, into which the hot water is admitted directly from the main pipe V through the meter V and reducingvalve V. Said converting-tank is constructed with partitions V,extending perpendicularly or otherwise in such a manner as to cause, the water to pass through a considerable distance before it is finally discharged 'into'the trap U and into the retnrnpipe U, said partitions being of unequal height and left open at their tops for the escape of steam, as shown in the drawings, the object being to retain the water for a sufficient length of time to enable the steam which is evaporated by the specific heat 'of the water to be thrown ofi before the conconsumed to be made, for it will be seen that if'a'given' amount of water is admitted into the apparatus at a. given temperature and discharged only after it has been reduced to a very much lower temperature nearly all the steam thrown 011 and used could be determined. In

this apparatus the hotwater-induction port would be controlled by the governor of the eng'ine's, and in that way the power would be regulated. The trap shown in Fig. 7 would be the proper kind of thing to use with this apparatus, as it would carry away all the water as fast as it was allowed to pass through the converting-tank, but would notpermit the escape of any steam, whereas an expansion or temperature trap could hardly be regulated so satisfactorily insuch cases as where the water would be required to be discharged above the steam generating point as required for power purposes.

' In Fig. is shown one form of a temperature steam-trap. It consists of along copper (or other soft material) tube, S, which is arranged to convey the water of condensation from the radiators. There are-two bars or rods, S, extending the full length of the tube S, which are attached to the same base. These rods carry on their opposite ends a fixed valve, T, which communicates with the valve-seat constructed on the end of the expansion-tube S. A discharge pipe, T, is attached to the expans on tube to 'convey away the water which passes through the valve T. In the operation of this trap the water of condensation will pass into the tube S, and will by its heat expand the same and cause it to close the opening'or valve T; but as soon as it has become sulfitubewill permit the water to pass out. As

the tube it will again expand and close the valve. By thismeans the water of condensation can be discharged at almost any temperature from the radiators, and thus the entire heat of the water admitted may be utilized in warming the building.

InjFig. (i I have shown one manner of pro tectin'g the pipes underground from radiation by covering them by some well-known nonconductorand inclosing them in a wooden box, W, arranged with'a space, W, to carry on the with the pipes and covering. The space or channel W isin communication with the streetsewer W by means of a pipe, 1 2. In Fig. 7 I have shown a trap for discharging the water. from the radiators. It is connected with the branch pipe B, leading to the street return-pipe. It is constructed by placing a movable diaphragm, B, between two concave cases, B, and then bolted together, thus holding the diaphragm firmly in its position. To this diaphragm is fastened a stem, B, carrying a valve, B, which opens and closes a port constructed in the barrel B, said barrel being rigidly attached to the lower side of the case B. The pipe B, which extends to the return-main, is connected below the valve, as shown. The barrel B' is also connected by means of a pipe, B, with the bottom of the radiaton or drip-pipe B, this latter connection beingmade with the barrel above the discharge-valve. Apipe, B extends from the drip-pipe to the upper side of the'diaphragmcases. There is also a pipe, B, extending from the lower side of the diaphragm-cases and connected to the upper end of the radiator or t to a pipe extending upward from the drippipe. In the operation of this trap it should be placed at the position where the water of condensation will flow into' it, and the pipes B and B arranged, as shown, to extend above and below the diaphragm, and when full of ciently cooled the contraction of the pipe or.

soon as the water begins to run hot through water that otherwise might come in contactwater said pipes will regulate the movements of the same, and thereby control the dischargevalve. It is evident that if the water should 7o be'drawn off from the radiators or from the connecting-pipe B and the column of water in B" were retained by reason of the connections with the lower side of the case B the pressure of the column upon theincreased area 7 5 of the diaphragm would cause it to move in an upward direction and carry with it the valve B"',.and thus prevent further discharge of water from the pipe B. So soon, however, as the accumulation of water in the pipe 13 and connecting-pipe B has brought about an equilibrium of pressure in the pipes 13 and B", the diaphragm will drop by the weight connected thereto, and the valve B will again be opened and the water permitted to How 8 5 out, and thus the operation will continue alternately.

In Fig. 8 I have shown one construction of a a valve for regulating the pressure. In this system for conveying heat and power the pipes 0 are to be provided with cocks or valves, as shown in Fig. 2, so that any section may be closed for repairs without interfering in any way with the constant supply, which can be furnished through other pipes connected thereto at the junctions of the. streets. This system will not only furnish power for running all kinds of engines, elevators, and heat for warming buildiugs,butit may also be employed through the agency of a steam or hot-water stove for all kinds of cooking and other culinary purposes, and thus a convenient, healthful, and economical supply of heat and power maybe delivered and utilized at a great distance from the generator without any appreciable loss from condensation or waste of water. The return-water may be admitted to the heater by means of automatic gravity-traps or feed-water apparatus in place of pumps, if desired. i

It is evident that many more modifications of the various features and parts of this invention; may be employed, which it is not deemed'necessary here to enumerate.

My invention is not limited to the specific form of pressure-reducer or means for convert- ,ing the hot water into steam shown and describcd; but any contruction which will operate to reduce the pressure and convert the hot water into steam may be employed without departing from the spirit of the invention.

Some of the parts which are herein shown and described are shown and more fullydescribed in Patent No. 208,633, granted to me October 1, 1878, and form no part of the invention claimed herein, but are included in order to more fully and clearly illustrate the said invention.

Having now described the nature of the said invention and explained the manner of carry 1 0 ing it into practical effect, I hereby declare that what I consider to be novel and original, and therefore claim and desire to secure. by

Letters Patent of the United States, is-'- and described.

2. In a hot-water and steam system, the combination of ply-pipe leading from and returning, to the heater, a pressure-reducing valve by which the hot water is converted into steam, a-radiator or other means for utilizing the steam, a system of return-pipes by which the water or conheat and power densation is returned to the heater, and means for forcing a circulation in the supply-pipes, substantially as shown and described.

3. In a hot-water heating system, the combination of a heater, a supply-pipe leading from and returning to the heater, a forcepump or other means for causinga circulation in the supply-pipe, a circulating coil or radiator or other means for utilizing the heat of the water, and a system of return-pipes by which the water, after being circulated for heating purposes, is returned to the heater, substantially as shown and described.

4. The combination of a heater, a supplypipe leading from and returning to the heater,

a force-pump, a hot-water engine. pipes con nectiug the engine with the supply-pipe, areturn-pipe, and pipes connecting the engine with the return-pipe, substantially as shown anddescribed.

5. The combination of a heater, a supplyplpe leading from and returning to the heater, a. force pump, the supply-pipe, and a preheater, as A, substantially as shown and described.

a heater, a superal blocks of the district,

a return-pipe independentbf the hot water,

6. The combination of the water heater, :1.

supply-pipeleading from and returning to the heater, a radiator or other means for utilizing a discharge-water trap, and a system of return-pipes communicating with the trap and heater and radiator for reconveying the water to the heater.

7. The combination, with the separate supply and return pipes, of the tank V, provided with the partitions extending from the bottom upward to within a short distance of the top,

' and the trap U, constructed and operating sub stantially as shown and described.

8. The combination of the hot-water-supply pipe leading from and returning to the heater, the return-pipe, the radiators, and the difierential discharge-water trap composed of the casings Bflthe diaphragm B, the stem B, the valve B, the barrel B, and pipes B, and the pipes 13 ,13, B, and B, substantially as shown and described. 1

9. In a central-station heat and powersystem, whereby heat and power are furnished to large districts of buildings in cities and towns, the combinationot a heater, a street supplypipe leading from and returning to the heater, a force-pump, a street return-pipe communicating with the heater, branch pipes leading from the supply-pipe to the building where heat; or power is required, branch return-pipes leading from the building and connecting with the street return-pipe, branch street supply and return pipes communicating with the main supply and return pipes, whereby the heating medium is circulated around the sevand'rneans for controlling the flow in each and every section.

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