IMPROVEMENTS IN APPARATUS FOR VENTILATING SHIPS HOLDS, APPLICABLE TO COAL AND OTHER CARGOES
Year: 1884

page_text: I GEORGE SUTHERLAND DODMAN of 6 Clarendon Terrace, Beaumont Street,
Liverpool, in the County of Lancaster, Engineer, do hereby declare the nature
of my said Invention for IMPROVEMENTS IN APPARATUS FOR VENTILATING
SHIPS HOLDS, APPLICABLE TO COAL AND OTHER CARGOES, to be as follows:-
.
'
My Invention has for its object the prevention of noxious, injurious, or dangerous
gases accumulating in ships holds, or 'tween decks and cargoes particularly in the
holds of ships carrying coal cargoes and grain cargoes. Such a prevention of
accumulation obviates all liability of explosion, or damage of goods, or cargoes as
the case may be.
My Invention consists as follows;―
The
Tubes are laid in the hold somewhat below the centre of the cargo, these tubes
are in sections, say eight feet long and are made of sheet iron, perforated say three
inches apart, sufficiently strong to resist any ordinary pressure. Each section is
provided with iron bands to strengthen same, the end band is fitted to form. a
flange for the next section, the end of extreme sections has a perforated cap.
sections are so constructed that when not in use, every other one telescopes into the
larger section thus occupying very little space when stowed away, cross sections are
provided for downcast and upcast shafts. The cross sections can be made in three,
or one.as size may require and fitted in the fore and aft tubes, say a little over a
fourth from each end, and can be regulated to any length of ship by having a
larger, or smaller receiver as occasion may require. -
A shaft from the deck is provided to the cross section and the part of the shaft
under the deck is made in two pieces of telescopic form to prevent any strain should
the cargo settle, also to allow the fitting of the fore and aft tubes and cross sections
without any exact level being required, the top and flange being convex and fitted
somewhat loose on deck under flange, so as to prevent strain should the cargo shift
slightly to either side, this is secured under the deck. This section is partly
perforated so that in the upcast, gas or heat having accumulated under the deck
may be withdrawn. Both upcast and downcast are perforated so that the deck
sections can be changed at will.
In the upcast and downcast pipes are fitted valves which can be closed at will
from the outside when necessary, for instance, in case of heavy weather suddenly

page_text: comming on, they can also be used to regulate, or stop the upcast when it is
necessary to force a circulation of air through the entire cargo. On the plate
shaft outside is a catch to regulate the draught, or hold same in position when
closed.
The downcast pipe is provided with a bell mouth fitted to work in any direction
to catch the wind, also handles to unship same, or regulate at will.
The upcast is similar in formation to the downcast, but has a stay fitted inside to
bold a stud. On this stud is worked an inside fan formed so as to draw with an
easy motion, the largest possible quantity of gas, or heat from the entire hold and
to this is fitted a small bevel wheel which is driven by a second one fitted on a
spindle worked in a bush and collar fitted in the side of the shaft. This mechanism
is driven from the outside on the same shaft by a fan, or fans capable of catching
the wind without regulating every time the wind changes a point. A back. draught
cowl may be applied to help the up current to clear itself speedily and create an
extra draught for the inside fan.
་
The outside fans are arranged to unship when the ventilators are required to be
stowed away.
The downcast and upcast can be reversed at will according to the
position of the wind; or as occasion may require.
In applying my Invention to a double decked ship the construction.of apparatus
is similar to that before described only that it is continued from one hold to the
other, with an addition in the 'tween decks shaft of a slide to close the cross section
when required, which is worked by a cross bar and connection, or bar and chain, or
in any other effectual and suitable method, the object of this is, say in the downcast
that the wind may not be sufficiently strong to fill the entire ship, so the 'tween
decks can be closed and the air conveyed to the lower hold, at the same time the
upcast deck plate can be regulated, or, closed the two will effect a complete
distribution of air throughout the lower hold. When it is required to draw the
lower hold the upcast 'tween decks can be closed.
'
By my Invention an uninterrupted current of air 'is caused to pass through the
entire ship and cargo, displacing gas and heat that may have been generated and so
preventing possibility of fire, or explosion.
.....

page_text: COMPLETE SPECIFICATION.
I GEORGE SUTHERLAND DODMAN, of 6 Clarendon Terrace, Beaumont •Street,
Liverpool, in the County of Lancaster, Engineer do hereby declare the nature of
my said Invention for IMPROVEMENTS IN APPARATUS FOR VENTILATING SHIPS
HOLDS, APPLICABLE TO COAL AND OTHER CARGOES and in what manner the same
is to be performed, to be particularly described and ascertained in and by the
following statement:-
My Invention has for its object the prevention of noxious, injurious, or dangerous
gases accumulating in ships holds, or 'tween decks and cargoes, particularly in the
holds of ships carrying coal cargoes and grain cargoes. Such a prevention of
accumulation obviates all liability of explosion, or damago of goods, or cargoes as
the case may be.
My Invention consists as follows
Tubes are laid in the hold somewhat below the centre of the cargo these tubes
are in sections and are made of sheet iron, perforated say three inches apart,
sufficiently strong to resist any ordinary pressure. Each section is provided with
iron bands to strengthen same; the end band is. fitted to form a flange for the next.
section, the end of extreme sections has a perforated cap. The sections, are so
constructed that when not in use, every other one telescopes into the larger section
thus occupying little space when stowed away, downcast and up cast shafts are
provided. The downcast and up cast shafts are fitted in the fore and aft tubes and
can be regulated to any tube as occasion may require.
The downcast and upcast shafts under the deck are made in two pieces.of
telescopic form to prevent any strain should the cargo settle, also to allow the
fitting of the fore and aft tubes without any exact level being required. Both
upcast and downcast are perforated so that the deck sections can be changed at
will and so that the gas and heat accumulated under the deck may be withdrawn.
In the upcast and downcast pipes are fitted valves which can be closed at will
from the outside when necessary, for instance in case of heavy weather suddenly
coming on, they can also be used to regulate, or stop the upcast when it is necessary.
to force a circulation of air through the entire cargo. On the valve shaft outside
is a catch to regulate the draught, or hold same in position when closed.
The downcast pipe is provided with a bell mouth fitted to work in any direction
to catch the wind also handles to unship same, or regulate at will.
The upcast is similar in formation to the downcast but has a back draught cowl
and has a stay fitted inside to hold a stud. On this stud is worked an inside
fan formed, so as to draw the largest possible quantity of gas, or heat from the
entire hold through the upcast, and on this stud is fitted a small bevel wheel which
is driven by a second bevel wheel fitted on a spindle worked in a bush fitted in
the side of the upcast shaft. This mechanism is driven from the outside on the
same shaft by a fan, or fans capable of catching the wind without regulating
every time the wind changes a point. A back draught cowl may be applied to
help the up current to clear itself speedily and create an extra draught for the
inside fan.
The outside fans are arranged to unship when the ventilators are required to be.
stowed away. The downcast and upcast can be reversed at will according to the
position of the wind, or as occasion may require, or the fan can be arranged to be
driven by hand

page_text: In applying my Invention to a double decked ship the construction of apparatus
is similar to that before described only that it is continued from one hold to the
other with an addition in the 'tween decks shaft of a slide to close the pipes of
each deck when required. The object of this, is say, in the downcast that the
wind may not be sufficiently strong to fill the entire ship, so the 'tween deoks can
be closed and the air conveyed to the lower hold, at the same time the upcast deck
valve can be regulated, or closed, and effect a complete distribution of air throughout
the lower hold.
C
By my Invention an uninterrupted current of air is caused to pass through the
entire ship and cargo, displacing gas and heat that may have been generated and so
preventing possibility of fire, or explosion.
.
The beforegoing being the general description of the nature, object and purposes
of my Invention, I will now proceed to set forth the same more clearly by the aid of
the two sheets of Drawings hereto annexed and which form part of this Specification.
The Drawings are marked with figures and letters of reference corresponding with
those in the following explanation, like letters and figures being used to denote the
same, or corresponding parts throughout the various views.
Figure 1 is a plan of a 'tween decks, or hold of a ship. provided with apparatus
according to my Invention.
Figure 2 is a modification of Figure 1.
Figure 3 is a plan of a ships "tween decks, or hold divided into compartments
by bulkheads, each compartment being provided with apparatus according to my
Invention.
Figure 4 is an elevation of the downcast shaft according to my Invention
partly in section, shown connected to the fore and aft pipes in the 'tween 'decks, or
hold.
'
Figure 5 is a sectional elevation of the upcast shaft according to my Invention.
Figure 6 is a sectional elevation of the continuation of either the upcast shaft, or
downcast shaft.
Figure 7 illustrates the shape of pipe I employ when placing my system for
*ventilating immediately under the deck.
Figure 8 is a side elevation of Figure 7.
Upon reference to the Drawings Figures 1, 2 and 3 it will be seen that A is a
plan outline of a ship and may represent the tween decks, or any of the holds.
According to my Invention, I place in the hold and somewhat below the centre of
the cargo the system of tubes B decreasing in size towards the ends of the vessel.
These tubes are constructed in sections and are made of sheet iron and are
perforated with holes throughout their length. Each section or length is provided
with iron strengthening bands 6 the end band of each section is so fitted as to
form a flange for the next section as shown at Figure 4 and the extreme ends are
provided with perforated caps. The sections, or lengths of tubes are made of such
diameter that when not in use, number one will ship into number three and
number two will ship into number four and so on thus occupying little space when
stowed away. In connection with the tubes B which are laid in duplicate as
shown at Figures 1, 2 and 3, I provide down cast and up cast shafts, namely one line
of tubes has downcast shafts, the other line of tubes has upeast shafts, the shafts
being constructed as hereinafter described, so that by changing the cowls, or above
deck lengths they can be changed from upcast into downcast or from downcast into
upcast. C are the downcast shafts and D are the upcast shafts, or their position
may be reversed. These shafts extend from the upper deck to the bottom timbers
of the ship, so that in cases of an emergency they can be used not only as
ventilating shafts, but as leads for bilge pumps, or fire engine pumps. The
construction of the downcast will be understood upon reference to Figure 4. It
consists of a vertical tube C-which is surmounted by a cowl E the mouth of which
is always kept facing the wind. The tube C is made in sections, telescoping one
within the other namely the section C¹ telescopes into the section C the upper
part of C¹ being perforated and lower part being perforated so that when

page_text: extended the perforations are open. The upper part of the section C³ is also
perforated under the deck H as shown. F is a cross piece, or section which
connects the downcast C to the horizontal pipes B. By moving the cross piece F
the section C¹ will draw down and fit over the section and in like manner to
that above described the downcast C may be in connection at the same time with
each systein of pipes within each of the decks, or hold, through the cross
pieces F F F as shown at Figures 4 and 6, or any one system of pipes of the
series may be disconnected by removing its cross connecting piece and dropping
the telescope section of the shaft C. The shaft C is provided with a valve, or
damper J by which the shaft can be closed, or the draught of air therethrough
regulated. The upcast shaft D is of similar construction to the downcast shaft C,
namely it is provided with cross pieces for connecting it to its pipes B and is
perforated and made to telescope in sections the same as the downcast C. It is also
provided with a valve, or damper K by which the passage of air through it can be
regulated, or by which it can be closed altogether. The cowl L of the upcast is
placed with its back to the wind and is provided with a back draught cowl M and
with a suction fan d. This suction fan d is driven by a bevel pinion and wheel e
which receives motion from a wind propeller which is carried by the spindle i
of the bevel wheel e. This propeller h is in duplicate, one on each side of the
cowl L.
When it is desirable, as in the case of ventilating saloons and passenger decks
on board ship that the pipes B should be as much as possible out of the way,
make the pipes B semi cylindrical in section and place them close under the deck H
as shown at Figures 7 and 8.
Having now particularly described the nature of my said Invention and
in what manner the same is to be performed I declare that what I claim is
First The means substantially herein described for ventilating ships, which
means consist of a system of perforated tubes (made in sections to ship into each
other when not in use) and connected to a downcast shaft, and a system of like
tubes connected to an upcast shaft, the tubes and shafts being constructed and fitted
as herein described and shown in the Drawings hereto annexed.
Second The particular construction of downcast shaft and upcast shaft and their
connection with a perforated tube system, whereby the said shafts can be connected
to all, or any one length of the tube system substantially as herein described and
shown in the Drawings hereto annexed.
Third The use in connection with the upcast shaft of a suction fan and wind
propellers for working same substantially as herein described and shown in
reference to Figure 5 of the Drawings hereto annexed.
Fourth The use in connection with the upcast shaft of a back cowl whereby a
current of air is caused to pass through the cowl and induce an up draught in the
cowl substantially as herein described and shown in reference to Figure 5 of the
Drawings hereto annexed.
Fifth The general arrangement and construction of apparatus for ventilating
ships holds substantially as herein described and shown in the Drawings hereto
annexed.