IMPROVEMENTS IN MARINE STEAM ENGINES AND BOILERS
Year: 1860

page_text: PROVISIONAL SPECIFICATION left by Robert Morrison at the Office
of the Commissioners of Patents, with his Petition, on the 15th February
1860.
I; ROBERT MORRISON, of the Town and County of the Town of Newcastle-
upon-Tyne, Engineer, do hereby declare the nature of the said Invention for
"IMPROVEMENTS IN MARINE STEAM ENGINES AND BOILERS," to be as follows:-
The first improvement relates to the boilers or steam generators, and con-
sists in constructing the shell of a cylindrical form, and fitting in it a conical
fire box, reaching up to within ten inches, more or less, of the water line;
these conical fire boxes are fitted with conical cross tubes, which not only
serve the double purpose of increasing the heating or absorbing surface and
staying the fire box internally, but cause a constant circulation of the water in
the boilers, and separate the particles composing the gases arising from the
burning of the coal, and thereby assist the process of combustion. I admit the
requisite quantity of air above the fire by the fire door or other means, and I
leave a large space above the fire, or between the fire and the conical tubes, to
enable the gases to mix sufficiently with the air and promote perfect combus-
tion. I arrange these boilers in a group, with the chimney standing upon the
same level as the boilers, and made nearly in the same way, except that the
conical fire boxes pass up beyond the water line and conduct the smoke into
the atmosphere. The boilers being arranged in a group with a certain space
between them, sufficient for the gases to pass into the chimney, the flame or

page_text: gases pass from the fire bars up through the horizontal conical tubes to the top
of the large fire box, the flame then passes out by an opening at or near the
top of the conical fire box, and then acts upon the outside of the boilers next
to each other, the top space between the group of boilers being closed by a
smoke door, and the boilers being placed so close together as to be air-tight,
the flame is confined and drawn towards the opening in the bottom of the
chimney, and on its way acts upon a surface equal to half the area of the shell
of each boiler, and afterwards' passes into the chimney, where it will heat the
feed water and also superheat the steam; the chimney for the boilers described
having a conical fire box similar to the boiler, and filled with small cross
conical tubes like the boilers. The feed water is first pumped into this
chimney, which communicates with all the boilers, to which the water passes
heated, and keeps at the same level in the boilers and chimney. The steam
from the top of all the boilers is conveyed into the top part of the chimney,
where it. has to pass through the small conical tubes, and is superheated to
any degree required before it passes through the main steam pipe to the
working cylinder."
The boilers may be arranged in a circular group, with the chimney in the
centre of the group, so that the heat will act upon the outside as well as on the
inside of it. I put the small conical tubes in the boiler and chimney either
horizontally or at an angle, and place them above one another either in crosses
or spirally, in such a manner that when looking up the top of the fire box
cannot be seen past them.
The next improvement in connection with steam boilers consists in making
a water guage, the glass of which will indicate the level of the water, say,
about five feet from the floor, or any convenient height that a man can see,
instead of the said glass being up at the water line; for this purpose I use a
ball or other float on the surface of the water, and I take a rod down from
that float to below where I intend to place the water guage; I bend the end
of this rod upwards and out through the shell of the boiler, so as to pass up
into and through the bottom of the guage glass'; I cover this rod in by a piece
of boiler plate, or other suitable means, to make it steam-tight; and being
guided inside of the boiler, when the level of the water alters in the boiler, the
float will rise or fall, as the case may be, and with it the rod, so that the
turned up point of the said rod will rise and fall in the gauge glass as the
water rises or falls in the boiler, and so indicate truly the water level in the
said boilers and chimney; I use the usual gauge cocks, but brought down by
pipes to the same level as the water gauge, so that the attendant can reach
them from the floor.

page_text: The condenser which I propose to employ is made with flat plates, stayed
or corrugated in such a manner as to resist the pressure and be easily cleaned;
for this purpose, I make the division of the condenser of copper plates, or other
suitable material with a space of about " between each plate, and I set the
edges of those plates together and rivet or brase them or a strip of copper.or
'other material; the thickness of the space may be fitted between the plates
and rivetted thereto. I stay such plates at proper intervals by screwed stays
and washers, or by setting or corrugating the plates together and rivetting
them, and having got the requisite number of divisións ready, I rivet or braze
the ends of each of the plates to each other, and put a flange plate round the
end of the whole; this flange to be of such a thickness and width as will allow
the condenser to expand or contract, as may be required.
I place this condenser in a cast or wrought iron or copper cistern made with
flanges to suit those on the condenser, leaving a space at top and bottom, and
I pump the cold water through each alternate space and admit the steam in
every other alternate space; by this arrangement I obtain a much larger.sur-
face for the purpose of condensation than can be obtained by the ordinary
means; whilst by removing the top of the condensing cistern the water spaces
of the surface condenser may be cleaned, and by taking off the side doors the
steam spaces may be cleaned without removing the condensing apparatus. .Or
the condenser may be removed by taking off the side door and removing the
bolts in the flanges or the keys, and cleaned, and it will be of such a size as
will admit of a spare one being carried, which can be readily and speedily sub-
stituted when required. Into this condenser I admit the steam from the
cylinders, also from the jackets of the cylinders, as well as from the donkey
pump, in such quantity as will make up for the loss of water by leakage, &c.,
so that the boilers will be constantly supplied with fresh water.
In one of my arrangements I put the surface condenser in the back frames
of the engines when they are of the inverted cylinder class; in the other I put
the condenser in a separate box or cistern between the said frames.
In my improved steam engines I use three cylinders for engines above
150 horse-power, and connect each to one solid crank axle, with the three
crank bearings placed in such a manner as will divide the circle into three
equal divisions, and I make the stroke of such a length as will enable me to
expand the steam nine to ten times.
For smaller engines I use two cylinders and balance the crank. I surround
the working cylinder with a steam jacket supplied from the donkey boiler at a
greater temperature and pressure than that supplied to the cylinders. I use
two steam and exhaust valves for each cylinder, as well as two expansive valves,

page_text: and in one of my arrangements for working these valves I use four eccentrics
fixed upon
the shaft, and the usual reversing link, and two eccentrics for the
expansion valves loose upon the shaft, and worked by proper stops fixed upon
the shaft; I also employ a link between the eccentric rod and the valve rod,
with a screw arranged in such a manner as to cut off the steam at any point of
the stroke required, an index being placed upon the said link or quadrant to
regulate such cut-off.
In my other arrangement I employ only two eccentrics for the steam valves
and two for the expansion valves, all loose upon the shaft, and worked by
proper catches fixed upon the said shaft; and I connect the rods direct to the
slide rods, and reverse the engines by two auxiliary valves for that purpose;
by this means I fix the cut-off permanently and beyond the control of the
engineer, and I am able to reverse the engines much quicker and with more
ease than can be done with the ordinary turning gear. I arrange the donkey
pump to supply the condenser with cold water, or supply the boiler with salt
or fresh water in case of accident to either the condenser or the pump for
supplying it.
When it is found desirable to expand the steam to fifteen or sixteen times,
I use three cylinders, and make the middle cylinder a high-pressure one and
the other two low-pressure cylinders; by this arrangement I obtain a great
amount of expansion. I prefer, however, in all cases, for the sake of simplicity,
to expand entirely in one cylinder.