IMPROVEMENTS IN OR CON- NECTED WITH STEAM HOISTING MACHINERY AS APPLIED ON SHIPBOARD
Year: 1879

page_text: LETTERS PATENT to Thomas Davison, of Glasgow, in the County of Lanark,
North Britain, Engineer, for the Invention of "IMPROVEMENTS IN OR CON-
NECTED WITH STEAM HOISTING MACHINERY AS APPLIED ON SHIPBOARD."
PROVISIONAL SPECIFICATION left by the said Thomas Davison at the Office
of the Commissioners of Patents on the 20th October 1879..
"
THOMAS DAVISON, of Glasgow, in the County of Lanark, North Britain, Engineer.
IMPROVEMENTS. IN OR CONNECTED WITH STEAM HOISTING MACHINERY AS APPLIED
ON SHIPBOARD."
-
This Invention has principally for its object to economise the fuel employed in
working steam hoisting machinery on shipboard, and the improvements are, of the
greater advantage the greater the number of winches, cranes, or other hoisting
machines there are on board a ship.
Hitherto steam winches applied on shipboard have commonly been worked on
what is known as the high-pressure system, and which is comparatively wasteful
of fuel; but in carrying out the present Invention the condensing system is
employed; and surface condensers are used by preference in order that the water
due to condensation may be returned to the boilers, whilst sea water or other water
may be used as the condensing medium.
.
In the case of a ship fitted with two or more steam winches a single condenser
is provided for all the winches, and is placed in the main engine room or stoke hole
of a steam-ship, or at any convenient part of a steam ship or sailing ship, but
generally apart from the winches, such condenser being connected by pipes to.the
exhaust passages of the steam cylinders, of the several winches. A small steam
engine is fitted in connection with the condenser with one or more air pumps for
clearing the condenser, also with one or more circulating pumps for forcing the sea
water or other cooling water through the condenser, and also with feed pumps for
supplying the boiler, which works the winches.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent filed by
the said Thomas Davison in the Great Seal Patent Office on the 16th April
1880.
THOMAS DAVISON, of Glasgow, in the County of Lanark, North Britain, Engineer.
"IMPROVEMENTS IN OR CONNECTED WITH STEAM HOISTING MACHINERY AS APPLIED
ON SHIPBOARD."
My said Invention has principally for its object to economise the fuel employed
in working steam hoisting machinery on shipboard, and my improvements are of
the greater advantage the greater the number of winches, cranes, or other hoisting
machines there are on board a ship.
Hitherto steam winches applied on shipboard have commonly been worked on
what is known as the high-pressure system, and which is comparatively wasteful
of fuel;
but in carrying out my present Invention I employ the condensing system,
and I use surface condensers by preference in order that the water due to conden-
sation may be returned to the boilers, whilst sea water or other water may be used
as the condensing medium.
In the case of a ship fitted with two or more steam winches a single condenser
is provided for all the winches, and is placed in the main engine room or in the
stoke hole of a steamship, or at any convenient part of a steamship or sailing ship,
but generally apart from the winches, such condenser being connected by pipes to
the exhaust passages of the steam cylinders of the several winches. A small steam
engine is fitted in connection with the condenser with one or more air pumps for
clearing the condenser, also with one or more circulating pumps for drawing or
forcing the sea water or other cooling water through the condenser, and also with
a feed pump or pumps for supplying the boiler which works the winches.
And in order that my said Invention and the manner of performing the same
may be properly understood I hereunto append two Sheets of explanatory
Drawings to be hereinafter referred to, and representing an example of my
improved arrangements or apparatus. In these Drawings the same reference
numerals are used to mark the same. or like parts wherever they are repeated.
Figure 1, on Sheet 1 of the accompanying Drawings, is a diagram, showing a
portion of a steamship in vertical longitudinal section. as fitted with my improved
apparatus; Figures 2 and 3, on Sheet 2, are a plan. and side elevation of a con-
venient arrangement of surface condenser with air pump, circulating: pump,, and
feed pump, and an engine for working them as. adapted for carrying out my
Invention; Figures 4 and 5 are. transverse and. longitudinal vertical sections. of
the air pump or of the circulating pump, the two pumps being alike;, and Figure 6
is an end elevation showing the surface condenser with the end cover removed..
The surface condenser 7 is an oblong rectangular casing placed, horizontally, and
fitted with horizontal tubes which are fixed in vertical tube plates 8. near the ends
of the casing 7. The circulating water has access to the tubes. by spaces or com-
partments between the tube plates. 8 and the end covers; the space at one end being
divided by a horizontal partition 9. The water enters by an inlet pipe 10
(Figures 1, 6,) into the space beneath the horizontal partition 9, and passes through
the lower half of the tubes to the space at the other end of the condenser, returning
through the upper half of the tubes to the space above the partition. 9. One side
of the condenser casing 7 is availed of for the attachment and support of the pumps
and other parts, no separate frame or soleplate being required. The circulating
pump 11, air pump 12, and steam cylinder 13 are placed all in the same line, their
several pistons being on one rod 14, which is made of such different .diameters at
different parts as to admit of the several pistons being conveniently fixed on it. The
piston rod 14 passes through stuffing boxes at both ends of all the cylinders, and

page_text: its extreme end serves as the plunger for the feed pump 15. At its other end the
piston rod is connected in the usual way to a crank shaft 16, which has a
flywheel 17 on it, and is carried across the end of the condenser in bearings fixed
to the end below the end cover. For convenience and economy the circulating
and air pumps,11, 12, are made exactly alike, so that parts of them may be cast
from the same patterns, their internal construction; and arrangement. being shown
in Figures 4 and 5, and being similar to such pumps: as ordinarily made in their
general features. An improved and convenient mode of arranging the valve seats
is however adopted. Each pump is double-acting with a single inlet valve 18 and
outlet valve 19 for each end, and the seats for the two valves 18, 19, at one end
are formed in one cylindrical casting 20, which can be withdrawn entire along with
the valves when the cover is off, and which is made with its inner part of reduced
diameter, and to fit the recesses or seats made for it in the main casting. The
guard of the outlet valve 19 is made with a spindle which extends to and passes
through the seat of the inlet valve 18, and by means of a shoulder secures the
guard of that valve, being itself fixed by a screw nut below the inlet valve seat 18.
The seat casting 20 is made with openings, one on its under side between the
valves 18, 19, to communicate with the pump, and the other on its upper side
outside of the discharge valve 19 to communicate with the discharge passage 21.
12.
The steam euters the condenser 7 by a pipe 22 at the top, and the water of
condensation passes by a passage 23 to the inlet valves 18 of the air pump
The condensing or steam space does not extend to the bottom of the casing 7,
there being a horizontal partition 24, the space below which forms a hot well or
reservoir, and the discharge passage of the air pump 12 communicates with the
hotwell by a passage 25, which besides leading thereto also extends upwards to an
outlet 26 for air. The feed pump 15 draws its supply from the hotwell space
beneath the partition 24 by a pipe 27, and a pipe 28 (Figure 1) conveys the feed
water to the donkey boiler 29. The circulating pump 11 draws the water from
the condenser casing 7 by an inclined passage 30 and discharges it by a pipe 31.
One of the steam winches 32 of the ship is shown in Figure 1, and a branch
pipe 32 is shown as proceeding from it to the steam inlet pipe 22 of the condenser,
whilst a similar pipe 33 is shown as extending to the other winch or winches of
the ship or to a crane or cranes or other hoisting machines. The pipes for leading
steam from the boiler or boilers to the winches are not shown, but may be arranged
in the ordinary way, and if convenient may be for the most part near the exhaust
pipes 32, 33.
It will be obvious that for the purposes of my Invention the condenser 7 and
parts immediately connected therewith may be arranged in a variety of ways, and
that in each case the arrangement of the main engines, if it is a steamship, or that
of other parts in the ship, will determine the best disposition for my improved
apparatus.
I may remark that the wastefulness of the high-pressure system is greatly
increased in the case of winches and similar machines by the great fluctuation in
the work, and that as a pressure of steam somewhat above the atmosphere is
necessary to turn the machine alone without any load it follows that proportionally
more is wasted with small loads, whereas with my improved system the consumption
of steam is very nearly in proportion to the actual work and is always compara-
tively small.
Having thus particularly described my said Invention, and the manner of
performing the same, I have to state that I do not restrict myself to the precise
details herein described or delineated, but that what I believe to be novel and
original, and claim as the Invention secured to me by and in terms of the herein-
Lefore in part recited Letters Patent, is,-
1. The connection of two or more steam winches or hoisting machines on board
a ship with one set of condensing apparatus, substantially as and for the purposes
herein before described.

page_text: "..
2. The combination of a surface condenser with circulating air and feed pumps
and a steam engine working these pumps for condensing the exhaust steam of a
winch or winches or other hoisting machinery on board a ship, as herein before
.described.
In witness whereof, I; the said Thomas Davison, have hereunto set my hand
and seal, this Fifteenth day of April, in the year of our Lord One thousand
eight hundred and eighty.
Witness,
EDMUND. HUNT,
Patent. Agent,
Glasgow.
THOS DAVISON. (L.S.)