IMPROVEMENTS IN STEAM SHIPS, ESPECIALLY IN THE CONSTRUCTION AND ARRANGEMENT OF THE BOILERS
Year: 1880

page_text: LETTERS PATENT to William Gray, of Dawlish, in the County of Devon, for
an Invention of "IMPROVEMENTS IN STEAM SHIPS, ESPECIALLY IN THE
CONSTRUCTION AND ARRANGEMENT OF THE BOILERS."
PROVISIONAL SPECIFICATION left by the said William Gray at the Office
of the Commissioners of Patents on the 30th April 1880.
WILLIAM GRAY, of Dawlish, in the County of Devon. "IMPROVEMENTS IN
STEAM SHIPS, ESPECIALLY IN THE CONSTRUCTION AND ARRANGEMENT OF THE
BOILERS."
This Invention has for its object improvements in steam ships, especially in the
construction and arrangement of the boilers.
The boilers are of the locomotive type, having an horizontal barrel containing
flue tubes, and a fire box at one end descending below the barrel. In place however
of having the fire door in the usual position at the back of the fire box I arrange
it at the front, and immediately underneath the barrel. I also mount the boiler
in such manner that there is sufficient space for the stokers between the floor of
the ship and the boiler, so that the stokers may work beneath the barrels of the
boilers. I provide each boiler with two furnaces, cach with its set of flue tubes in
the barrel, and between these two sets of fluc tubes I arrange circulating plates to
conduct a descending column of water downwards between the two sets of tubes.
1 also apply a circulating plate at the front of the fire box, separating an ascending
current against the inner plate of the fire box from a descending current passing
along the outer plate thereof. Also to insure a more perfect combustion a brick
arch is turned in each fire box beneath the flue tubes in such manner as to compel
the products of combustion to pass beneath the arch towards the front of the firo
box, and to return over the top of it to reach the tubes. I provide tanks in the
bottom of the ship to store fresh water for the use of the boilers, and to replenish
the store I arrange pipes, by which rain water falling on the decks in rainy
weather may be permitted to drain into the boiler supply tanks.
Over each lower boiler I erect an upper boiler of saddle like form, and I provide
flue tubes in the saddle as in the main boiler. The products of combustion from
the furnances after passing through the tubes of the main boiler are led back

page_text: through the tubes of the upper or saddle boiler and so reach the chimney. Or in
place of employing saddle boilers in the manner described I combine with two
boilers in the lower tier an upper boiler consisting of an horizontal barrel with flue
tubes passing through it, and the products of combustion from the furnaces of the
lower boilers after traversing the tubes of these boilers are conducted back through
the tubes of the upper boiler, and so they reach the chimney.
I connect the steam domes of the lower boilers with the upper boiler by pipes
with stop cocks, so that steam may be admitted from the lower boilers into the
upper to equalize the pressure.
The steam is taken to the ongines from the steam domes of the lower boilers.
The feed water for the supply of the lower or main boilers is drawn from the
upper boiler or boilers, which are thus supplied with water which is already in an
highly heated state.
A convenient arrangement is to force the feed water by means of the feed pumps
or injectors into the upper boiler or boilers, and to allow the feed water to descend
from these into the lower boilers past suitable check or retaining valves.
SPECIFICATION in pursuance of the conditions of the Letters Patent filed by
the said William Gray in the Great Seal Patent Office on the 30th October
1880.
WILLIAM GRAY, of Dawlish, in the County of Devon. "IMPROVEMENTS IN
STEAM SHIPS, ESPECIALLY IN THE CONSTRUCTION AND ARRANGEMENT OF THE
BOILERS."
This Invention has for its object improvements in steam ships, especially in the
construction and arrangement of the boilers.
The boilers are of the locomotive type, having an horizontal barrel containing
flue tubes, and a fire box at one end descending below the barrel. In place however
of having the fire door in the usual position at the back of the fire box I arrange
it at the front, and immediately underneath the barrel. I also mount the boiler
in such manner that there is sufficient space for the stokers between the floor of
the ship and the boiler, so that the stokers may work beneath the barrels of the
boilers. I provide each boiler with two furnaces, each with its set of flue tubes in
the barrel, and between these two sets of flue tubes I arrange circulating plates to
conduct a descending column of water downwards between the two sets of tubes.
I also apply a circulating plate at the front of the fire box, separating an ascending
current against the inner plate of the fire box from a descending current passing
along the outer plate thereof. Also to insure a more perfect combustion a brick
arch is turned in each fire box beneath the fluc tubes in such manner as to compel
the products of combustion to pass beneath the arch towards the front of the fire
box and to return over the top of it to reach the tubes. I provide tanks in the
bottom of the ship to store fresh water for the use of the boilers, and to replenish

page_text: h, h, are fresh water store tanks in the bottom of the ship for the supply of the
boilers, and i, i, are pipes by which rain water may be permitted to drain into
them from the deck.
Figures 3 and 4 show to a larger scale an arrangement in which two lower
boilers are employed in combination with one upper boiler, which in this caso is
cylindrical in formn. The several parts are lettered to correspond to the description
already given.
In this arrangement the steam domes of the three boilers are shown connected,
so that the same pressure will be maintained in all. k, k, are the pipes by which
water is drawn as required from the the upper boiler to supply the lower boilers; it
is continued up within the boiler, that the water cannot be drawn down to stand at
too low a level in the upper boiler.
Having thus described the nature of my said Invention, and the manner of
performing the same, I would have it understood that I claim in relation to my
Invention of improvements in steam ships, especially in the construction and
arrangement of the boilers,-
First. The construction and arrangement of the boilers of steam ships with the
firing doors at the front of the fire boxes, and with the firing space beneath the
barrels of the boilers and between them and the floor of the ship.
Second. The combination of a lower boiler or boilers of locomotive type with an
upper tubular boiler, and causing the products of combustion from the furnaces to
pass first through the tubes of the lower boiler and then to return through the
tubes of the upper boiler to the chimney.
Third. The arrangements for storing water for the supply of the boilers in store
tanks formed in the bottom of the ship, and provided with pipes, by means of
which rain water falling upon the deck of the ship may be led into the said store
tanks.
Fourth. The construction of locomotive like boilers of steam ships with firing
doors in front, double or divided furnaces, arches within the furnaces, and cir-
culating plates and pipes, substantially as described.
Fifth. The construction and arrangement of the boilers of steam ships, sub-
stantially as described and represented in the annexed Drawings.
In witness whereof, I, the said William Gray, have hereunto set my hand and
scal, this Twenty seventh day of October, in the year of our Lord One
thousand eight hundred and eighty.
M