Year: 1885

page_text: I ALFRED FERNANDEZ YARROW of the Firm of Yarrow and Company of the
Isle of Dogs Poplar Shipbuilders do hereby declare the nature of this Invention
to be as follows:-
This Invention relates to arrangements for supplying heated air to the furnaces
of. Steam Boilers used in Torpedo and other vessels of a similar nature working
under a forced draught.
According to my Invention the air is forced by a fan into the stoke-hole com-
partment from whence it is forced to the other end of the boiler to the smoke box
compartment where it is heated by an arrangement of heated tubes or other
convenient means and from thence it is forced back to the furnace so supplying the
air required for combustion in a highly heated state:
:
L
J. HENRY JOHNSON,
Agent for the said Alfred Fernandez Yarrow.

page_text: °
Improvements in the Mode of Supplying Air to Steam Boilers
for Torpedo and other similar Vessels.
i
I ALFRED FERNANDEZ YARROW of the Firm of Yarrow and Company of the
Isle of Dogs Poplar Shipbuilders, do hereby declare the nature of this invention
and in what manner the same is to be performed, to be particularly described
and ascertained in and by the following statement :—
This Invention relates to arrangements for supplying heated air to the furnaces
of Steam Boilers used in Torpedo boats and other vessels of a similar nature
working under a forced draught.
According to my Invention the air is forced by a fan into the stoke-hole com-
partment from whence it is forced to the other end of the boiler to the smoke box
compartment where it is heated by an arrangement of heated tubes or other
convenient means and from thence it is forced back and into the furnace so
supplying in a highly heated state the air required for combustion.
In order that my Invention may be well understood I will particularly describe
the same with reference to the accompanying drawing whereof Figure 1 is a
longitudinal section elevation and Figure 2 a cross sectional elevation (taken on the
line K. L Figure 1) of part of a Torpedo Boat fitted with an arrangement according
to my Invention..
A is the boiler which is shewn as being of the locomotive type and built into the
Boat by the Bulkheads B and C. Figure 1.
These bulkheads are furnished with apertures D. E F on each side of the boiler
for the passage of air supplied by a fan pump or jet.or any suitable apparatus for
the purpose. The apertures are fitted with non return flame doors opening in the
direction of the forced air current. The apertures D and E are divided from the
apertures F F by the horizontal plate or division G G extending on each side of
the boiler barrel from the bulkhead B to the smoke box H which is removed a
certain distance from the boiler end so as to admit of the introduction of a number
of thin heating tubes J forming a continuation of the boiler tubes through which
the products of combustion pass from the furnace on their way to the chimney
The division G forms the space between the bulkheads B and C into two passages
and has an opening to allow the air after passing along the upper passage to
descend through an opening in the division G and pass between the tubes J to
the lower passage.
The forced air draught enters at the openings D and the air passes along the
top of the boiler and through the openings EE and through the spaces between
the tubes J and there becomes heated by the waste gases which are escaping to the
chimney or funnel and the air thus heated returns through the openings FF
beneath the boiler barrel and enters the fire-box through the ash hole or other inlet
provided for the purpose.
I do not limit myself to the precise details shewn in the drawing as it will
be evident that they may be varied without departing from the nature of my

page_text: Invention. For example the tubes J may be replaced by any suitable arrangement
of surfaces which are heated so as to impart the requisite heat to the air.
Having now particularly described and ascertained the nature of my said
Invention and in what manner the same is to be performed I declare that what
I claim is,-
For supplying air to the furnaces of the steam boilers of Torpedo boats or other
like vessels an arrangement of air passages by which the draught of air is led
forward to or towards the smoke box end of the boiler and is there passed over
heating tubes or other equivalent heating surfaces and is then returned and supplied
to the furnace substantially as herein before described.
1000