FORM-2
THE PATENTS ACT, 1970
(39 of 1970)
&
THE PATENTS RULES, 2003
PROVISIONAL
Specification
(See section 10 and rule 13)
BOILER
THERMAX LIMITED
an Indian Company
Chinchwad, Pune411 019, Maharashtra, India
THE FOLLOWING SPECIFICATION DESCRIBES THE INVENTION.
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FIELD OF INVENTION:
This invention relates to Boilers.
This invention more particularly relates to an oil/gas fired Boiler system. Envisaged in accordance with this invention is a boiler, which is outside the purview of IBR.
PRIOR ART:
It is already known in the prior art that there are oil/gas fired boilers in which the water hold-up is less than 22.75 litres and hence they are outside the purview of Indian boiler regulation.
Such boilers are essentially made of a single coil and a feed water pump, which circulates water through the coil. The water before being pumped is heated in an un-pressurized water pre-heater which is external to the coil system.
OBJECTS OF THE INVENTION:
An object of this invention is to provide an improved boiler in which the water hold-up is maintained below 22.75 litres.
SUMMARY OF THE INVENTION:
It is envisaged in this invention that there is a boiler having two concentric coils. The inner coil generates steam while the outer coil facilitates the preheating of water. The water hold-up of inner pressurized coil is maintained below 22.75 litres.
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The boiler unit of this invention comprises an inner helical coil, forming the furnace either of a straight flue or of a reverse flue design, and an outer coil connected to a water service tank.
ADVANTAGES OF THE NEW BOILER
There is provided a Compact boiler with integral water pre-heater, which is not under the purview of Indian Boiler Regulation.
BRIEF DESCRIPTION OF THE DRAWING:
The invention will be described in detail with reference to a preferred
embodiment. Reference to this embodiment does not limit the scope of the
invention.
In the accompanying drawing:
Figure 1 illustrates the schematic design of the proposed system of this
invention.
Reference numeral (1) is a Furnace or combustion chamber. From one end fuel is fired axially by any known means and the air is supplied either by blower/blowers (6). The furnace design can either be of straight flue or reverse flue type, forced draft or natural draft. In the straight flue type the products of combustion exit from the rear end of the furnace and in the reverse flue type the products of combustion exit from the front end of the furnace.
The Furnace or combustion chamber is made of tubes, helically wound in closed coil or with flats made of metals like steel, aluminium, copper or a combination of these metals to form a membrane coil. The products of
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combustion, exiting the furnace enters the annular between the inner furnace coil and a shell jacket assembly section cooled by combustion air forming the air pre-heater (3) and then continues to flow through the annular between the outer coil (2) and furnace inner coil, exchanging heat with both inner and outer coil. The outer convection coil is made of tubes helically wound with single or multi start arrangement either closed coil or open coil or water wall coil. The bottom and the top end of this coil are connected to the water service tank (4) and the water circulates through the outer coil by natural circulation and gets pre-heated by exchanging heat with the products of combustion. The pre-heated water is then pumped by the feed-water-pump (5) into the inner furnace coil.
The heat from the exiting flue gases from the annuli of the inner and outer coil may or may not be further recovered by any known means of heat recovery like air pre-heating and oil pre-heating.
While considerable emphasis has been placed herein on the specific
structure of the preferred embodiment, it will be appreciated that many alterations can be made and that many modifications can be made in the preferred embodiment without departing from the principles of the
invention.
These and other changes in the preferred embodiment as well as other embodiments of the invention will be apparent to those skilled in the art from the disclosure herein, whereby it is to be distinctly understood that the
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foregoing descriptive matter is to be interpreted merely as illustrative of the invention and not as a limitation.
Dated this 7th.day of April 2006

Mohan Dewan
of R. K. Dewan & Co
Applicant's Patent Attorney

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