IE57044B1

IE57044B1 - A vertical boiler

Info

Publication number: IE57044B1
Application number: IE44386A
Authority: IE
Original assignee: Pubavon Ltd
Priority date: 1986-02-20
Filing date: 1986-02-20
Publication date: 1992-03-25
Also published as: BE1000033A7; GB2187271A; GB8703880D0; GB2187271B; IE860443L

Abstract

A vertical boiler 1 has a heat transfer enclosure formed by water carrying side walls 2, front wall and rear wall 4. An gas duct 25 is formed against the side and front walls of an upper chamber of the boiler. The duct 25 is defined by a channel shaped retaining plate 31 which engages against a plurality of vertical fins 32 projecting from the side walls 2 and the front wall 3 to divide the duct 25 into a plurality of smaller vertically extending ducts. To promote heat transfer a flow restricting zig-zag shaped baffle 33 is located in each smaller duct. The baffles 33 are a rattle fit in the ducts 30 and are removable, as is the plate 31, for cleaning. An upper baffle plate 42 extends across the top of the upper chamber 20 to direct hot combustion gases downwardly to the enter the gas duct 25 at its lower end.

Description

The present invention relates to boiler® and more particularly but not exclusively to oil and gaa fired boilers of the type often referred to as, vertical enclosed or free-standing boilers.

Generally speaking, vertical boilers have a heat transfer enclosure formed from a aide wall at least some of which is hollow for reception of water, the said enclosure defining a lower combustion chamber and an upper chamber communicating with a gas outlet flue. The side wall of the enclosure may in fact be formed from eteparwte interconnected walls forming a hot water jacket. The boiler is usually rectangular in cross-section.

The major problem with such boilers is to ensure that the heat transfer surfaces which are arranged for contact with the hot flue gases of combustion transfer the heat efficiently to the water contained within the heat transfer wall with minimum soot deposits. This means therefore, that the heat transfer surfaces and the arrangement of the flow of the combustion gases within the boiler must be correctly arranged so as to ensure an adequate heat exchange between the flowing combustion v tn gases and the liquid surrounding the yes passageway» Ona of the major problems that arises Is that the beet transfer surfaces often become coated with soot end other deposits depending on the type of fuel used» Accordingly, the heat transfer surfaces must be regularly cleaned. Unless very elaborate methods of cleaning of the accumulated soot are provided it is necessary to have removable panels or other means of access to the boiler for cleaning it» χθ The present invention is directed towards providing bii improved construction of vertical boiler which will have sufficient thermal efficiency and at the same time will be more easily cleaned than conventional vertical boilers.

According to the invention there is provided a vertical boiler having a heat transfer enclosure formed from a I side wall at least some of which is hollow for carrying water, the enclosure defining a lower combustion chamber and on upper chamber communicating with a gas outlet flue, the boiler further comprising an inner duct formed against at least a portion of the side well of the upper chamber to direct hot combustion gases from the combustion chamber against the heat conducting surfaces of the sidewall to on upper discharge outlet to an exhaust gas flue, the duct being formed by a retaining plate spaced-apart from the side wall, paid retaining plate abutting a plurality of substantially vertically arranged heat exchanger fins projecting from the side wall to form a plurality of substantially vertically extending smaller ducts, each smaller duct including a baffle in the form of ts plate member bent lo bock and forth to form a zig-zag configuration, the plate alternately contacting or projecting adjacent the side wall and retaining plate, wherein each baffle Is a loose or rattle fit in Its corresponding duct to be removable for cleaning and includes e hook member at its upper end for suspension from the boiler plate.

In one embodiment of the Invention an upper baffle plate -5extends substantially across the upper chamber to divert the flue gases entering th® upper chamber to the lower combustion gas inlet to the duct» Preferably the restrictors removable for cleaning« Xn a preferred embodiment of the invention the retaining plate is removable for cleaning» The invention will be more clearly understood from the following description of some embodiments thereof given by way of example only with reference to the accompanying IO drawings in which* Fig. 1 is e cut-away perspective view from the front of a boiler according to the invention; Fig» 2 is a cut-away perspective view o£ the boiler from the rear; IS Fig* 3 is a typical vertical side section through the boiler; and Fig* 4 is a plan view of the boiler with a lid removed.

I -6Keferring to the .drawings there is illustrated a vertical boiler indicated generally by the reference numeral 1 having a heat transfer enclosure formed by a side wall which in this case comprises a pair of side walls 2f a front wall 3 and a rear wall 4. There is further a base 5 and a removable top cover 6 mounted on etude 7 and incorporating a conventional seal 8 of asbestos rope. A gas exit flue 10 is mounted by means of a plate 9 on the rear wall 4. The walls 2, 3 and 4 are hollow water jackets of conventional construction and are connected to a water heating system by an inlet pipe 11 and an outlet pipe 12. A door 15 incorporating a hole 16 for a burner, not shown, is mounted on the front wall 3 and further incorporates a viewing flap 17.

The interior of the boiler 1 is divided into an upper chamber 20 and a lower combustion chamber 21. An inner gas duct indicated generally by the reference numeral 25 is formed against the side walls 2 and the front wall 3 of the upper chamber 20 and has a lower flue gas inlet 26 in the combustion chamber 21 and an exit 27 adjacent the top of the boiler and below the cover 6. The Inner gas duct 25 I comprises a plurality of separate smaller ducjts 30 formed by a channel-shaped retaining plate 31 abutting against a plurality of substantially vertically arranged heat exchanger fins 32 projecting from the front wall 3 and -T side walls 2. Each duct 30 incorporates a flow restrictor formed by a removable baffle 33 which is formed from a plate bent back and forth on itaelf to a sig-sag £ihep® to alternately contact or project adjacent the walla 2 or front wall 3 of the upper chamber and the retaining plat® 31o Each baffle 33 i® a loo&e or rattle fit in the smaller gas duct 30 for ease of removal and to promote combustion gas flow through the ducts 30. Each baffle 33 is formed into a hook 34 at its upper end so that they may be suspended from the retaining plate 31 as can b^ seen from the drawings. A number of hooks 34 may be connected together by a connector piece to allow a number of the baffles to be removed simultaneously. In turn the retaining plate 31 is removably mounted on the side walls 2 and front wall 3 by a plurality of support tabs 35. The retaining plate 31 also includes a plurality of outwardly projecting lugs 36.

A removable upper baffle plate 42 having a handle 43 is mounted' on the lugs 36. The baffle plate 42 ia flush against the rear wall 4 and apaced-apart slightly from the retaining plate 31 adjacent the front wall 3· In use, and referring particularly to Fig. 2 combustion gaee© shown by th© arrows are driven into the combustion chamber 21 and against the walls 2, 3 and 4. The gases »9then travel up along the rear wall 4 and are directed downwardly by th® top plots 42. The majority of the combustion gases are delivered to the lower inlet of the inner gas duct 25.' The hot flue gases rising through the inner gas duct 25 are delivered out the exit at 27 and across the upper chamber 20 to the flue 10. VA small proportion of the exhaust gases which rise to th The Invention has certain major advantages. Firstly, the use of the zig-zag baffle plates and the inner gas duct ensures that the majority of the flue gases cone into contact with what are effectively the heat exchange surfaces of the boiler thus promoting adequate heat transfer between the hot flue gases and the transfer medium which is normally water. Further, the construction is such that on removal of the lid 6 the retaining plate and the zig-zag baffles may be lifted out of the boiler.

It is also possible to lift out the upper baffle plate 42. Thus, it will be appreciated that the boiler is particularly suited for cleaning and further it will have a high thermal efficiency.

It will be appreciated that the boiler may be of any -9suitable horizontal cross section for example circular or rectangular .

It will also be appreciated that in some cases additional baffle plates may be provided to direct combustion gases for increased heat transfer efficiency. It is also envisaged that the baffle plates may be provided by wafer tanks.

Claims

1. A vertical boiler having a beet transfer enclosure formed from a side wall at least some of which is hollow for carrying water, the enclosuie defining a lower * combustion chamber and an upper chamber communicating with a gas outlet flue, the boiler further comprising an inner duct formed against at least a portion of the side wall of the upper chamber to direct hot combustion gases from a lower combustion gas inlet at the combustion 1° chamber against the heat conducting surfaces of the side wall to an upper discharge outlet to an exhaust gas flue, the duct being formed by a retaining plate spacedapart from the side wall, said retaining plate abutting a plurality of substantially vertically arranged jiieat 15 exchanger fins projecting from the side wall to form a plurality of substantially vertically extending smeller ducts, each smaller duct including a baffle in the form of a plate member bent back and forth to form a ssig-sag configuration, the plate alternately contacting or 20 projecting adjacent the side wall and retaining plate, wherein each baffle is a loose or rattle fit in its corresponding duct to be removable for cleaning and includes a hook member at its upper end for suspension from the boiler plate. 25

2. · A vertical boiler as claimed In claim 1, wherein the hook member is arranged for suspension from the retaining plate.

3. A vertical boiler as claimed in claim 1 or 2 in which the retaining plate is removable for cleaning.

4. A vertical boiler as claimed in any preceding claim in which an upper baffle plate extends substantially 5. Across the upper chamber to divert the flue gases entering the upper chamber to the lower combustion gas inlet.

5. A vertical boiler as claimed in claim 4 in which the upper baffle plate is removable for cleaning.

6. 10 6. A vertical boiler substantially as hereinbefore described with reference to the accompanying drawings.