GB2277982A - A boiler - Google Patents

Abstract

A gas or oil fired enclosed boiler 1 comprises a base 2, a top 3, a main rear tank, a main front tank 5 and a pair of main side tanks 6, 7 which define at least one enclosure through which flame and hot gases are led from a burner 12 to an exhaust flue 16. A removable cover for cleaning access is provided, e.g. at 26. Four baffle assemblies are provided in the boiler. Adjacent transverse baffle plates 30, 31, 32, 33 are longitudinally spaced-apart to define interconnected transverse passageways. Deflectors 51, 52, 53 are welded to the baffle plates and direct hot gases against the water-carrying surfaces of the boiler. The baffle plate assemblies are removable for cleaning. Adjustable damper means 54a, 54b, are provided for controlling the flow and/or temperature of the flow gases exiting from the boiler. The baffle plates 30 - 33 may be defined by water tanks. The deflectors may be defined by a central water tank extending through the boiler. The boiler may be upwardly or downwardly firing. <IMAGE>

Description

"A Boiler" The invention relates to boilers and especially to an enclosed boiler particularly a boiler which is fired by an oil or a gas burner.

Many different constructions of enclosed boiler are known.

There is, however, a need for an improved construction of such boilers which are as thermally efficient as possible and yet may be easily cleaned.

This invention is directed towards providing such an improved construction of boiler.

According to the invention, there is provided an enclosed boiler comprising: a base; a top; sidewall tank means extending between the base and top and defining therewith an enclosure through which hot gases are led from an inlet to a flue gas outlet, the enclosure having an accessway through which access is gained for cleaning; at least two transverse bridging means extending transversely at least partially across the enclosure; adjacent transverse bridging means being longitudinally spaced-apart to define therebetween transverse passageway means through which hot gases are led;; each bridging means defining an opening, the opening in one bridging means defining an inlet through which hot gases are introduced into the transverse passageway means and the opening in a following bridging means defining an outlet through which the hot gases are led from the passageway means; and deflecting means within the transverse passageway for directing hot gases for heat transfer as the gases are led through the passageway means; and adjustable damper means for controlling the flow of gases through the passageway means.

In one embodiment of the invention, the adjustable damper means is provided adjacent the flue gas outlet.

In a particularly preferred arrangement the adjustable damper means comprises a damper plate means which is movable into and out of the passageway means to control the flow of gases through the passageway means.

Preferably the damper plate means is slidably movable across the passageway means. Alternatively the damper plate means is rotatably mounted for movement across the passageway means.

In one arrangement there are two flue gas passageway means, each of which is provided with an adjustable damper means. In this case typically the damper means are independently adjustable.

In a preferred embodiment of the invention the or each damper means is mounted to the bridging means.

In one arrangement the bridging means includes two outlet openings which are selectively opened or closed or partially opened or closed by the damper means.

Preferably, the damper means comprises a number of mounting locations corresponding to the desired opening, closing or partial opening or closing of the outlet openings. Typically the mounting locations comprise a projection or hole for engagement with a complementary projection or hole in the bridging means.

In one embodiment of the invention, the openings defined by adjacent bridging means are offset.

In one arrangement the deflecting means is arranged to define with the sidewall means a flue gas passageway of substantially constant cross-section along its length.

In one embodiment of the invention the transverse crosssectional area of the passageway is greater than or equal to the cross-sectional are of the opening.

Preferably there are at least three transverse bridging means defining two interconnected longitudinally spacedapart transverse flue gas passageways. Most preferably there are at least four transverse bridging means defining three interconnected longitudinally spaced-apart transverse flue gas passageways.

In another embodiment the deflecting means includes watercarrying tank means.

In one arrangement the transverse bridging means comprises a transversely extending baffle plate means.

In a particularly preferred embodiment of the invention the deflecting means and/or bridging means are removable through the accessway for cleaning.

In one arrangement the deflecting means is mounted to an associated bridging means.

In one embodiment of the invention, the sidewall means is substantially rectangular in transverse cross section and comprises a front portion, a rear portion and a pair of side portions extending between the front and the rear portions, at least portion of the sidewall means being arranged for carrying water to be heated.

In one arrangement the deflecting means is arranged to turn the gases through at least 1800 on passing through each transverse passageway means. The deflecting means may be arranged to turn the gases through at least 360" on passing through each transverse passageway means.

In this case preferably the deflecting means comprises a pair of side portions which are each substantially parallel with and spaced-apart from the sidewall portion of the boiler sidewall means, and a front portion substantially abutting a front portion of the boiler sidewall and following the contour of the inlet and outlet openings to direct gases into and out of the transverse passageway. The deflecting means may include a rear portion substantially parallel with and spaced-apart from the rear portion of the sidewall means.

In one embodiment of the invention the deflecting means includes or is defined by a deflecting water-carrying tank means extending into the enclosure. Preferably the deflecting tank means extends from the front of the boiler and is spaced-apart from the rear of the boiler to define therewith part of the passageway.In another embodiment of the invention the additional deflecting means are provided which is spaced-apart from the sidewall means and the deflecting means to define further legs of a transverse passageway through which the hot gases are led.

Preferably the hot gases are split between two separate inlets to separate passageways from which the gases are discharged to a common boiler outlet. In one case an additional longitudinal bridging means extends between the sidewall means to divide the enclosure into two subenclosures. Typically each passageway is provided with bridging means and deflecting means for defining two transverse passageways through which the hot gases are led. Preferably the additional longitudinal bridging means is provided by an additional tank bridging the sidewall means.

In one embodiment of the invention an auxiliary watercarrying means extending between the sidewall means adjacent to the hot gas inlet.

In one arrangement, the accessway is provided in the top of the boiler.

Alternatively the accessway is provided on the sidewall means of the boiler.

In one embodiment of the invention, the base of the boiler is at least partially defined by a water-carrying bottom tank.

In one arrangement the top of the boiler has an opening defining the flue gas outlet. Alternatively the boiler is a down-fired boiler, the inlet the inlet being provided adjacent the top of the boiler and the outlet being provided adjacent the base of the boiler.

In one embodiment of the invention hot gases are delivered to the inlet from a burner. The burner may be a gas or oil burner.

The invention will be more clearly understood from the following description thereof, given by way of example only, with reference to the accompanying drawings, in which: Fig. 1 is a perspective partially cut-away view of a boiler according to the invention; Fig. 2 is a perspective view of a baffle arrangement of the boiler; Figs. 3 to 5 are plan views in the directions of the arrows III, IV and V, respectively in Fig. 1; Fig. 6 is an exploded view of the baffle arrangement of Fig. 2; Fig. 7 is an exploded view of the baffle arrangement of another boiler according to the invention; Figs. 8 and 9 are respectively perspective and plan views of another boiler according to the invention; Fig. 10 is a plan view of part of a boiler similar to the boiler of Figs. 8 and 9;; Fig. 11 is a perspective, partially cut-away, view of a further boiler according to the invention, and Fig. 12 is a perspective, partially exploded, view of a baffle system used in the boiler of Fig. 11.

Referring to the drawings and initially to Figs. 1 to 6, there is illustrated an enclosed boiler according to the invention indicated generally by reference numeral 1. The enclosed boiler 1 is, in this case, of generally rectangular shape in transverse cross-section and comprises a base 2, a top 3 and a water-carrying sidewall tank means comprising a main rear tank 4, a main front tank 5 and a pair of main side tank 6, 7 which define an enclosure through which flame and hot gases are led from an inlet which in this case is supplied by an oil burner 12, to an outlet 15 in the top 3 of the boiler to an exhaust gas flue 16. Water is circulated through the water-carrying tanks 4, 5, 6, 7 for water circulation through the boiler form a water inlet to a water outlet (not shown) which are typically connected into a hot water central heating system.In this case, the top of the boiler 3 is defined by an upper flue plate 25 having an outlet 15 therein for connection to the outlet flue 16 and a removable cover 26 over an accessway 27 through which access is gained for maintenance and cleaning of the boiler, as will be described in more detail below.

Alternatively the front of the boiler may at least be partially defined by a removable or movable cover over an accessway.

The boiler 1 is provided with at least two, and in this case, four transverse bridging means extending transversely across the enclosure. Each of the bridging means are, in this case, defined by transversely extending spaced-apart baffle plates 30, 31, 32, 33, the lowermost 30 of which is supported on mounting lugs 35 on the front, rear and sidewalls of the boiler. Adjacent transverse baffle plates 30, 31, 32, 33 are longitudinally spacedapart to define therebetween transverse passageways 40 through which the hot gases from the burner are led. The baffle plate 30 is cut-away at the front thereof to define together with the adjacent front and side tanks of the boiler and inlet opening 50 through which gases are led into the first transverse passageway 40 defined between the baffle plate 30 and the following baffle plate 31.

Similarly, the baffle plate 31 is cut-away to define an outlet opening 45 through which the gases are led from the transverse passageway 40 into the following transverse passageway defined between the plates 30 and 32.

Similarly, the baffle plate 32 is cut-away to define an opening 46 for leading the gases from the second transverse passageway into the third transverse passageway defined between the transverse plates 32, 33 and the baffle plate 33 is also cut-away at 47 to define an opening into the final transverse passageway before discharge into the exhaust gas flue 16. The area of the openings is preferably less than or equal to the transverse cross sectional area of the passageway.

Deflecting means for directing hot gases passing through the transverse passageways 40 against the water-carrying tanks of the boiler is, in this case provided by first, second, third and fourth deflector plate means 50, 51, 52, 54 welded to the respective transverse baffle plates 30, 31, 32, 33 respectively. The deflecting means in this case turn the gases through substantially 1800 as they travel through a passageway.Each of the first, second and third deflector plate means 51, 52, 53 are of similar shape and comprise a rear portion 60 which is substantially parallel with and spaced-apart from the rear tank of the boiler, a pair of side portions 62, 63 which are substantially parallel with and spaced-apart from the side tanks of the boiler and a front portion 64 which is of generally apex shape and extends to substantially abut the front tank 5 of the boiler 1 and follows the contour of the inlet and outlet openings 50, 45, 46 to direct hot gases into an outlet of the respective transverse passageways.

In this case, the fourth and uppermost deflecting plate means 54 directs the gases rising from the opening 47 defined by the transverse baffle plate 33 into the flue gas outlet of the boiler. The deflector 54 defines an adjustable damper means to control the flow of gases through the gas passageways. The adjustable damper plate means in this case comprises two parts 54a, 54b, one 54b of which is attached to the plate 33 and the other 54a of which is slidably mounted by means of a pin 55 and slot 56 to the part 54b for movement to vary the width of the passageway leading to the flue gas outlet. In this way the damper may be readily adjusted to achieve a desired flue gas flow and/or temperature. It will of course be appreciated that both plate parts 54a, 54b may be adjustable, for example by adjustable mounting to the plate 33 and/or any other suitable mounting location.

The second baffle plate 31 and associated deflector means 51 is mounted in use on the lower deflecting means 50.

Similarly the third baffle plate 32 and associated deflector means 52 is mounted on the second deflector plate means 51. The uppermost baffle plate 33 and associated deflector plate means 53 is in turn mounted on the third deflector plate means 52. In this way the baffle plates and associated deflector plates can be easily removed through the top access opening for cleaning by first removing the uppermost baffle plate 33 followed by the remaining baffle plate and associated deflector means. For ease of handling, the baffle plates may be provided with handles.

In use, and referring particularly to Figs. 1 and 6 with the baffle plates and deflector means in position and the accessway closed, the burner 12 is activated and hot gases and flames from the burner are projected from the burner 12 towards the rear tank 4 of the boiler where they are turned and lick the surfaces of the side tanks 6, 7 and front tank 5 of the boiler before passing through the opening 50 into the first transverse passageway 40. In the transverse passageway 40 they are initially directed rearwardly, then sidewardly along the rear tank 4 and forwardly before passing through the opening 45 into the following transverse passageway. This process is continued as illustrated in Figs. 1 and 6.

Because of the configuration of the baffle plates and deflector plates, a very high heat transfer efficiency is obtained because the hot gases must travel a long distance over the surfaces of the water-carrying tanks of the boiler, giving up a large proportion of their heat before discharge to the exhaust gas flue. Before cleaning, the access cover is removed and the baffle plates and deflector plates are readily removed as described above.

Referring to Fig. 7 there is illustrated another arrangement of baffles/deflector means for use with the boiler described with reference to Figs. 1 to 6. The arrangement is similar to the arrangement illustrated in Fig. 6 except that in this case the rear portion is omitted. This provides for ease of construction and free flow of gases through the passageway.

It will be appreciated that each of the deflector plate means may be of any desired shape and arrangement. For example, a substantially triangular or six or more sided shaped arrangement may be provided. It will also be appreciated that the deflector plate means may be provided, at least in part, by water-carrying tank means.

Referring to Figs. 8 and 9 there is illustrated another boiler 100 according to the invention which is similar to the boiler described with reference to Figs. 1 to 6, and like parts are assigned the same reference numerals. In this case a deflecting tank means 101 extends into the enclosure from the front tank 5 towards but spaced-apart from the rear tank 4 and the gases are deflected as illustrated particularly in Fig. 8 for enhanced heat transfer. Typically the baffle plate 30 is supported on the tank 101 and the additional baffle plates 31, 32, 33 are supported on the lowermost baffle plate 30.

In this case the flow and/or temperature of the gases discharged to the outlet is controlled by means of an adjustable baffle plate 107 which is attached by means of studs or bolts 108 and slots 109 to the plate 33. The flow of gases may be readily adjusted by varying the position of the baffle plate 107 as illustrated by the arrows X.

Referring to Fig. 10 there is illustrated a portion of another boiler 110 which is similar to the boiler 100 and like parts are assigned the same reference numerals. In this case additional deflector plate means 111, 112, 113 are provided spaced-apart from the tank 101 and the rear tank 4 and side tanks 6, 7 to define a transverse passageway through which the gases are led as illustrated.

In this case the gases are turned substantially through 360" as they pass through each transverse passageway for improved heat transfer.

Referring to Figs. 11 and 12 there is illustrated another boiler 120 according to the invention which is similar to the boiler of Figs. 1 to 6 and like parts are assigned the same reference numerals. In this case an additional tank 121 extends between the front tank 5 and rear tank 4 dividing the enclosure into two adjacent sub-enclosures 122, 123, each of which is provided with baffle plates 124, 125 and associated deflector plates 126, 127 which are arranged to turn the gases through substantially 1800 as they travel through each transverse passageway of the sub-enclosure 122, 123. The flame and hot gases from the burner are divided between two inlets 128, 129, for each sub-enclosure and the gases are combined at the outlets from the sub-enclosures 122, 123 for discharge through a common flue gas outlet.

In this case there are four baffle plates 124a, b, c, d, and 125a, b, c, d for each sub-enclosure. One of the deflector and baffle plate assemblies is shown in Fig. 12 The other is identical. The uppermost baffle plate 124d, 125d, is in this case provided with two openings 131, 132 which are closable by a damper plate 133. The damper plate 133 is provided with three locating holes 134a, b, c which are engageable by a bolt 135 extending from the baffle plate 124d, 125d. When the bolt 135 is in damper plate hole 134a the opening 131 is fully closed and the opening 132 is fully open. In the hole 134c the opening 131 is fully open and the opening 132 is closed. In the intermediate position represented by the hole 134b the damper plate 133 partially closes both the openings 131 and 132.In this way the flow of gases through the enclosure may be readily controlled to achieve a desired efficiency and outlet flue gas temperature.

When the damper plate 133 closes off the opening 132 the gases pass directly from the opening 131 to the flue gas outlet. Thus, the number of heat exchanging passes of the gases through the enclosure is reduced by one. In the intermediate position only a portion of the gases are directed into a final heat exchanging pass. This intermediate position is illustrated in dotted outline in Fig. 12.

It will of course be appreciated that the damper plate may be mounted in such a way as to permit any one of a It will of course be appreciated that the damper plate may be mounted in such a way as to permit any one of a plurality of set positions to be selected. While for ease of adjustment the damper plate is in the cases illustrated positioned at or adjacent to the front of the upper most baffle plate, in use it will be appreciated that it may be located in any desired position.

Many variations on the specific embodiments of the invention described will be readily apparent. For example, the boiler may be of any desired shape and configuration, such as, cylindrical, hexagonal, etc. The manufacturing costs, however, would likely be considerably greater than for the flat plate construction of the specific embodiments described.

It will also be appreciated that while for ease of cleaning, the bridging means and deflector means are, in most cases, of plate material, at least some of them may be defined by water-carrying tanks for enhanced heat transfer. For example, the deflector means may be defined by a central tank extending through the boiler.

It will further be appreciated that an accessway may be provided at any suitable location. For example, the front and/or one or both sides of the boiler may be provided with the accessway.

It will also be appreciated that the boiler may be a downfiring boiler.

The boiler may include an auxiliary tank adjacent the burner. This may, for example, be in the form of a tube of gun barrel material for carrying water to further These and many other changes and modifications will be readily apparent and accordingly, the invention is not limited to the embodiments hereinbefore described, but may be varied in both construction and detail.

Claims (43)

1. An enclosed boiler comprising a base; a top; sidewall means extending between the base and top and defining therewith an enclosure through which hot gases are led from an inlet to a flue gas outlet, the enclosure having an accessway through which access is gained for cleaning; at least two transverse bridging means extending transversely at least partially across the enclosure; adjacent transverse bridging means being longitudinally spaced-apart to define therebetween transverse passageway means through which hot gases are led; each bridging means defining an opening, the opening in one bridging means defining an inlet through which hot gases are introduced into the transverse passageway means and the opening in a following bridging means defining an outlet through which the hot gases are led from the passageway means; and deflecting means within the transverse passageway for directing hot gases for heat transfer as the gases are led through the passageway means; and adjustable damper means for controlling the flow of gases through the passageway means.

2. A boiler as claimed in claim 1 wherein the adjustable damper means is provided adjacent the flue gas outlet.

3. A boiler as claimed in claim 1 or 2 wherein the adjustable damper means comprises a damper plate means which is movable into and out of the passageway means to control the flow of gases through the passageway means.

4. A boiler as claimed in claim 3 wherein the damper plate means is slidably movable across the passageway means.

5. A boiler as claimed in claim 3 wherein the damper plate means is rotatably mounted for movement across the passageway means.

6. A boiler as claimed in any preceding claim wherein there are two flue gas passageway means, each of which is provided with an adjustable damper means.

7. A boiler as claimed in claim 6 wherein the damper means are independently adjustable.

8. A boiler as claimed in any preceding claim wherein the or each damper means is mounted to the bridging means.

9. A boiler as claimed in claim 8 wherein the bridging means includes two outlet openings which are selectively opened or closed or partially opened or closed by the damper means.

10. A boiler as claimed in claim 9, wherein the damper means comprises a number of mounting locations corresponding to the desired opening, closing or partial opening or closing of the outlet openings.

11. A boiler as claimed in claim 10 wherein the mounting locations comprise a projection or hole for engagement with a complementary projection or hole in the bridging means.

12. A boiler as claimed in any of claims 1 to 11, wherein the openings defined by adjacent bridging means are offset.

13. A boiler as claimed in any of claims 1 to 12, wherein the deflecting means is arranged to define with the sidewall means a flue gas passageway of substantially constant cross-section along its length.

14. A boiler as claimed in any preceding claim wherein the transverse cross-sectional area of the passageway is greater than or equal to the cross sectional area of the opening.

15. A boiler as claimed in any preceding claim, wherein there are at least three transverse bridging means defining two interconnected longitudinally spaced-apart transverse flue gas passageways,

16. A boiler as claimed in any preceding claim, wnerein there are at least four transverse bridging means defining three interconnected longitudinally spaced-apart transverse flue gas passageways.

17. A boiler as claimed in any preceding claim wherein the deflecting means includes water-carrying tank means.

18. A boiler as claimed in any preceding claim, wherein the transverse bridging means comprises a transversely extending baffle plate means.

19. A boiler a claimed in any preceding claim, wherein the deflecting means and/or bridging means are removable through the accessway for cleaning.

20. A boiler as claimed in any preceding claim wherein the deflecting means is mounted to an associated bridging means.

21. A boiler as claimed in any preceding claim in which the sidewall means is substantially rectangular in transverse cross section and comprises a front portion, a rear portion and a pair of side portions extending between the front and the rear portions, at least portion of the sidewall means being arranged for carrying water to be heated.

22. A boiler as claimed in any preceding claim wherein the deflecting means is arranged to turn the gases through at least 1800 on passing through each transverse passageway means.

23. A boiler as claimed in claim 22 wherein the deflecting means is arranged to turn the gases through at least 3600 on passing through each transverse passageway means.

24. A boiler as claimed in any of claims 21 to 23, wherein the deflecting means comprises a pair of side portions which are each substantially parallel with and spaced-apart from the sidewall portion of the boiler sidewall means, and a front portion substantially abutting a front portion of the boiler sidewall and following the contour of the inlet and outlet openings to direct gases into and out of the transverse passageway.

25. A boiler as claimed in claim 24 wherein the deflecting means includes a rear portion substantially parallel with and spaced apart from the rear portion of the sidewall means.

26. A boiler as claimed in any of claims 21 to 24 wherein the deflecting means includes or is defined by a deflecting water-carrying tank means extending into the enclosure.

27. A boiler as claimed in claim 26, wherein the deflecting tank means extends from the front of the boiler and is spaced-apart from the rear of the boiler to define therewith part of the passageway.

28. A boiler as claimed in any preceding claim wherein additional deflecting means are provided which is spaced-apart from the sidewall means and the deflecting means to define further legs of a transverse passageway through which the hot gases are led.

29. A boiler as claimed in any preceding claim wherein the hot gases are split between two separate inlets to separate passageways from which the gases are discharged to a common boiler outlet.

30. A boiler as claimed in claim 29 wherein an additional longitudinal bridging means extends between the sidewall means to divide the enclosure into two sub-enclosures.

31. A boiler as claimed in claim 30 wherein each passageway is provided with bridging means and deflecting means for defining two transverse passageways through which the hot gases are led.

32. A boiler a claimed in claim 30 or 31 wherein the additional longitudinal bridging means is provided by an additional tank bridging the sidewall means.

33. A boiler as claimed in any preceding claim including an auxiliary water-carrying means extending between the sidewall means adjacent to the hot gas inlet.

34. A boiler as claimed in claim 33 wherein the auxiliary water-carrying means comprises a water carrying tube extending between the sidewall means.

35. A boiler as claimed in any preceding claim, wherein the accessway is provided on the top of the boiler,

36. A boiler as claimed in any of claims 1 to 34 wherein the accessway is provided on the sidewall means of the boiler.

37. A boiler as claimed in any preceding claim wherein the base of the boiler is at least partially defined by a water-carrying bottom tank.

38. A boiler as claimed in any preceding claim, wherein the top of the boiler has an opening defining the flue gas outlet.

39. A boiler as claimed in any of claims 1 to 37 wherein the boiler is a down-fired boiler, the inlet being provided adjacent the top of the boiler and the outlet being provided adjacent the base of the boiler.

40. A boiler as claimed in any preceding claim, wherein hot gases are delivered to the inlet from a burner.

41. A boiler as claimed in claim 40, wherein the burner is an oil burner.

42. A boiler as claimed in claim 40, wherein the burner is a gas burner.

43. A boiler substantially as hereinbefore described with reference to the accompanying drawings.