FIRE TUBE BOILER

Abstract

A fire tube boiler, comprising a jacket for containing water to be heated and a tube bundle designed to convey exhaust gases, which is accommodated within the jacket, the boiler comprising at least two furnaces with a corresponding burner connected to a single tube plate to which the tubes of the tube bundle are connected at one end, the tubes leading at their end into an exhaust gas collection chamber.

Description

TECHNICAL FIELD

The invention relates to a fire tube boiler.

BACKGROUND ART

It is known that the heat source of thermal systems that require high power is often provided by means of a battery of fire tube boilers connected in parallel.

In conditions of high heat demand, such battery operates optimally, because all the boilers that compose it, conveniently balanced, are operating, but when heat demand decreases, the burner of one or more boilers is turned off: thus, the corresponding boiler remains unused, with all the negative consequences that notoriously arise from the loss of continuity of operation.

DISCLOSURE OF THE INVENTION

The aim of the present invention is to provide a fire tube boiler that can be installed as a heat source in thermal systems requiring high capacities, ensuring continuity of operation as the heat demand conditions vary.

This aim and these and other objects which will become better apparent hereinafter are achieved by a fire tube boiler, according to the invention, characterized in that it comprises the features disclosed in the appended claims.

BRIEF DESCRIPTION OF THE DRAWINGS

Further characteristics and advantages of the invention will become better apparent from the description of two preferred but not exclusive embodiments of the fire tube boiler according to the invention, illustrated by way of non-limiting example in the accompanying drawings, wherein:

FIGS. 1 and 2 are views of a battery of boilers connected in parallel according to the background art, in two different operating conditions;

FIG. 3 is a sectional view of the boiler according to the invention according to a first embodiment;

FIG. 4 is a view of the boiler according to the invention according to a second embodiment.

WAYS OF CARRYING OUT THE INVENTION

With reference to FIGS. 1 and 2, the reference numerals 1 and 2 designate two fire tube boilers according to the background art, which are connected in parallel so as to form a battery.

The boilers 1 and 2 are identical, and therefore the boiler 1 comprises a jacket 3 for containing the water 4 to be heated and is provided, at the top, with a furnace 5 in which the flame produced by a burner 6 develops.

The furnace 5 has a base shaped like a tube plate 7, from which a plurality of tubes 8 extend; said tubes are immersed in the water 4 to be heated and convey the exhaust gases produced in the furnace 5 to a chamber 9 for collection and conveyance to the stack.

The boiler 2, as mentioned, is identical to the boiler 1.

The situation shown in FIG. 1 is the full-capacity situation: the burner 6 of the boiler 1 and the corresponding burner of the boiler 2 are on, as highlighted in the figure, and thus both boilers, balanced appropriately, are operating and the situation is optimum.

FIG. 2 instead shows the situation that occurs as a consequence of a reduction in heat demand: the burner of the boiler 2 has shut down and accordingly the entire boiler 2 remains unused.

FIG. 3 is a view of a first embodiment 10 of a boiler according to the invention which comprises a jacket 11, for containing the water 12 to be heated, with connectors 11a, 11b respectively for inflow and outflow.

Inside the jacket 11 two furnaces 13 and 14 are provided, with corresponding burners 13a, 14a, which have a common base constituted by a tube plate 15, which is thus connected to both furnaces 13 and 14.

Tubes 16 of the tube bundle are connected to the tube plate 15, are immersed in the water to be heated and convey the exhaust gases generated in the two furnaces 13 and 14, or in at least one of them, to a chamber 17 for collection and conveyance to the stack.

When only one of the burners is operating, as is the case in FIG. 3, in which only a burner 13a is on, the exhaust gases that it produces affect all the tubes of the tube bundle, according to the arrows in the figure, with consequent full use of the boiler and with the additional advantageous feature of achieving a great reduction in the temperature of the exhaust gases in output, with consequent increase in efficiency, due to the large exchange surface that is offered to the exhaust gases in the indicated condition.

FIG. 4 shows a second embodiment of the invention, in which two furnaces 18 and 19, with respective burners 18a, 19a, instead of being side by side as in the embodiment of FIG. 3, are superimposed, but in any case always both connected to a tube plate 20 to which tubes 21 of the tube bundle are connected; such tubes are immersed in the water to be heated and convey the exhaust gases produced in both furnaces, or in only one of them, as is the case of FIG. 4, in which only the burner 18a is on, with the flow of exhaust gases highlighted by the arrows, to a collection chamber 22.

In practice it has been found that the boiler according to the invention fully achieves the intended aim.

The described invention is susceptible of numerous other modifications and variations, all of which are within the scope of the appended claims: moreover, all the details may be replaced with other technically equivalent elements.

The disclosures in Italian Patent Application No. MI2010A001418 from which this application claims priority are incorporated herein by reference.

Where technical features mentioned in any claim are followed by reference signs, those reference signs have been included for the sole purpose of increasing the intelligibility of the claims and accordingly such reference signs do not have any limiting effect on the interpretation of each element identified by way of example by such reference signs.

Claims

1-3. (canceled)

4. A fire tube boiler, comprising a jacket for containing water to be heated and a tube bundle designed to convey exhaust gases, which is accommodated within said jacket, further comprising at least two furnaces with a corresponding burner connected to a single tube plate to which tubes of said tube bundle are connected at one end, said tubes leading at their end into an exhaust gas collection chamber.

5. The boiler according to claim 4, wherein said at least two furnaces are arranged side by side.

6. The boiler according to claim 4, wherein said at least two furnaces are arranged so that one lies above the other.