IMPROVE- MENTS IN AND CONNECTED WITH STEAM ENGINES
Year: 1871

page_text: LETTERS PATENT to James Weir, of Glasgow, in the County of
Lanark, North Britain, Engineer, for the Invention of " IMPROVE-
MENTS IN AND CONNECTED WITH STEAM ENGINES."-Partly a commu-
PROVISIONAL SPECIFICATION left by the said James Weir at the
Office of the Commissioners of Patents, with his Petition, on the
22nd July 1871.
I, JAMES WEIR, of Glasgow, in the County of Lanark, North Britain,
Engineer, do hereby declare the nature of the said Invention for "Im-
PROVEMENTS IN AND CONNECTED WITH STEAM ENGINES," (which Invention has
been in part communicated to me from abroad by George Weir, residing
at Marseilles, and is in part of my own Invention,) to be as follows, that
is to say:
This Invention comprises various improvements in and connected
with steam engines, and has for its objects to render such engines more
efficient and to economise fuel.

page_text: The first part of the Invention relates to the application of the exhaust
steam for heating the feed water, and may be carried out most advan-
tageously in connection with surface condensation, although also appli-
cable with jet condensation or with exhaust into the atmosphere. With
ordinary slide and other valves governing the entrance and exit of the
steam to and from the cylinder the effective back pressure in the
cylinder during the exhaust is never so low as the minimum in the
condenser; and one improvement consists in taking advantage of this
difference of pressure and consequent excess of temperature over that
in the condenser, by applying an adjustable valve in the entrance to the
condenser, and thereby as it were extending the difference of pressure
to the passage between the cylinder and condenser, or to a chamber,
enlargement, or feed heater forming part of such passage, and by in-
jecting into the feed heater or passage the water due to condensation
This feed water
in the main condenser before feeding it into the boiler.
is, by preference, transferred from the main condenser to the feed heater
by a special pump or pumps, common or centrifugal, apart from the
usual air pump.
In working with these improved arrangements the engineer will
gradually close what may be termed the condenser throttle valve, at
least so long as such closing does not produce any appreciable increase
of back pressure in the cylinder, and he may even find that some
increase of the back pressure may be more than counterbalanced by the
cconomy of fuel effected by the consequent improved heating of the
feed water.
By a second improvement the same objects are sought to be attained
in a modified form but similar in principle. A chamber or feed heater
is arranged in connection with the cylinder, but not forming any part
A special port with
of the passage through to the main condenser.
passage leading to this feed heater is provided in the usual cylinder
port face, or in a separate port face, and the main slide valve or a
separate valve is arranged to open the communication from the cylinder
to the feed heater at suitable periods. The steam of comparatively
higher pressure and temperature exhausts into the feed heater and heats
the feed water therein, whilst on the pressure of the exhaust steam
diminishing below a predetermined limit a check valve fitted to the
feed heater closes and prevents the pressure therein from becoming
reduced. There may be two or more such separate feed heaters arranged

page_text: for different pressures, and the feed water may be passed first through
the one with the lowest pressures, and then in succession through each
with higher pressure, being either mixed with the steam or passed
through tubes or passages heated by the steam. Also the steam may
be admitted into the feed heater or heaters at periods more or less before
the usual period of main exhaust as may be found most advantageous
in practice.
By a third improvement applicable along with the first or second
improvement, or separately, the entrance into the main condenser is
made at the bottom thereof, and by preference so that the entering
steam blows through a shallow layer of the water of condensation, which
last is thereby rendered hotter than it otherwise would be.
A fourth improvement relates to the pumping of very hot feed water
into the boiler, which is attended with practical difficulty from the vapo-
risation of the water under the diminished pressure due to the sucking
action of the pump, and it consists in using two or more successive
pumps with an air vessel between them, or preferably with a substitute
for an air vessel herein-after described as the fifth improvement.
A fifth improvement consists in using on the delivery pipes of the
feed pumps, and instead of air vessels, which do not act satisfactorily
with hot water, either flexible metallic diaphragms or plungers working
through stuffing boxes, and either with springs applied externally, the
object being to avoid the effects of the concussive action of the pumps'
reciprocation.
The next part of the Invention relates to the working of steam
expansively through two or more cylinders in succession. One if not the
principal advantage of working steam through a number of cylinders
consists in there being a much smaller change of temperature in each
cylinder than there is in a single cylinder, in which the steam is worked
to the same degree of expansion. There has, however, been considerable
difficulty with such engines when starting, or reversing, or working
very slowly, which difficulty has greatly interfered with the otherwise
advantageous extension of the system.
By an improvement constituting the sixth of this Invention, reducing
valves (various kinds of which are well known as applied to other pur-
poses) are fitted in connection with the second valve casing, or with
each valve casing excepting the first, the reducing valve to each casing
being weighted or proportioned to admit thereto steam of the diminished

page_text: pressure suitable for working the corresponding cylinder. The reducing
valve or valves will receive their steam from the main steam pipe by a
branch or branches, which may be fitted with a stop valve or valves
whereby the steam can be shut off from the reducing valves when the
engines have not to be frequently started or reversed. Or the reducing
valves may be arranged with the full-pressure steam constantly admitted
to them, but being in such case weighted or proportioned to admit
somewhat lower pressures than those in the casings when the engines
are working regularly, so that the valves will act only when the
pressures in the casings are deficient.
SPECIFICATION in pursuance of the conditions of the Letters Patent,
filed by the said James Weir in the Great Seal Patent Office on
the 20th January 1872.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, JAMES
WEIR, of Glasgow, in the County of Lanark, North Britain, Engineer,
send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her
Letters Patent, bearing date the Twenty-second day of July, in the year
of our Lord One thousand eight hundred and seventy-one, in the thirty-
fifth year of Her reign, did, for Herself, Her heirs and successors, give
and grant unto me, the said James Weir, Her special licence that I, the
said James Weir, my executors, administrators, and assigns, or such
others as I, the said James Weir, my executors, administrators, and
assigns, should at any time agree with, and no others, from time to
time and at all times thereafter during the term therein expressed, should
and lawfully might make, use, exercise, and vend, within the United
Kingdom of Great Britain and Ireland, the Channel Islands, and Isle
of Man, an Invention for "IMPROVEMENTS IN AND CONNECTED WITH STEAM
ENGINES," the same being partly a communication to me from abroad
by George Weir, residing at Marseilles, and in part of my own In-
vention, upon the condition (amongst others) that I, the said James
Weir, my executors or administrators, by an instrument in writing under
my, or their, or one of their hands and seals, should particularly describe
and ascertain the nature of the said Invention, and in what manner

page_text: the same was to be performed, and cause the same to be filed in the
Great Seal Patent Office within six calendar months next and imme-
diately after the date of the said Letters Patent.
NOW KNOW YE, that I, the said James Weir, do hereby declare
the nature of my said Invention, and in what manner the same is to be
performed, to be particularly described and ascertained in and by the
following statement in writing, reference being had to the accompanying
Drawings, that is to say :-
The said Invention comprises various improvements in and connected
with steam engines, and has for its objects to render such engines more
efficient and to economise fuel.
And in order that the said Invention and the manner of performing
the same may be properly understood, I hereunto append two Sheets of
explanatory Drawings to be herein-after referred to, and representing
applications of my improvements.
In these Drawings the same reference numerals are used to mark the
same or like parts wherever they are repeated.
The first part of the Invention relates to the application of the
exhaust steam for heating the feed water, and may be carried out most
advantageously in connection with surface condensation, although also
applicable with jet condensation or with exhaust into the atmosphere.
With ordinary slide and other valves governing the entrance and exit
of the steam to and from the cylinder the effective back pressure in the
cylinder during the exhaust is never so low as the minimum in the
condenser, and one improvement consists in taking advantage of this
difference of pressure and consequent excess of temperature over that
in the condenser by applying an adjustable valve in the entrance to the
condenser, and thereby as it were extending the difference of pressure
to the passage between the cylinder and condenser or to a chamber,
enlargement, or feed heater forming part of such passage, and by in-
jecting into the feed heater or passage the water due to condensation in
the main condenser before feeding it into the boiler.
Figure 1, on Sheet 1 of the Drawings, is a plan, and Figure 2 is a
sectional end elevation of a three-cylinder compound inverted screw
propeller engine as fitted with some of the improvements comprised
in the present Invention, but with numerous well-known details not
shown.

page_text: An adjustable valve 4 is fitted in the passage 5 leading from the third
and largest cylinder 3 to the condenser 6, and a feed heating chamber
or enlargement 7 is formed in communication with the passage 5. The
water of condensation is led from the condenser 6 by a pipe 8 to a
special pump 9, whence it passes up by a pipe 10 to a rose 11 in the
feed heater 7, and becoming heated there by the fresh exhaust steam
passes on by the pipe 12 to the boiler feed pumps.
In working with these improved arrangements the engineer will
gradually close what may be termed the condenser throttle valve 4,
at least so long as such closing does not produce any appreciable
increase of back pressure in the cylinder, and he may even find that
some increase of the back pressure will be more than counterbalanced
by the economy of fuel effected by the consequent improved heating
of the feed water.
A second improvement by which the same objects are sought to be
attained in a modified form but similar in principle is shown in
Figures 3 and 4 on Sheet 2 of the Drawings, these Figures being
respectively a sectional end elevation and a sectional plan of a two-
cylinder compound inverted screw propeller engine. A chamber or feed
heater 7 is arranged in connection with the cylinder 2, but not forming
any part of the passage 5 through to the main condenser 6. A special
port with passage 13 leading to this feed heater is provided in the usual
cylinder port face (or it might be in a separate port face), and the
main slide valve 14, shown in sectional face view in Figure 5 (or a
separate valve), is arranged to open the communication from the
cylinder to the feed heater at suitable periods. The valve 14 is made
with narrow ports 15 which open to the opposite cylinder ports in each
case just before the cylinder port is uncovered to the main exhaust, and
each valve port communicates by a passage in the back of the valve
with a valve port 16 at the side which communicates with the port
and passage 13 leading to the feed heater 7, there being a port and
passage 13 on each side, although only one is shown in the Drawing,
and each passage 13 communicating with the feed heater through a
separate check valve, such as is indicated by dotted lines at 17 in
Figure 3. The pipe 18 by which the steam enters the feed heater
projects downwards, so that the steam may pass into the feed water
which is pumped up by the pipe 10, as in the first modification, and
passes off by the pipe 12. Steam of comparatively higher pressure and
temperature exhausts into the feed heater, whilst on the pressure of the

page_text: exhaust steam diminishing below a predetermined limit the check
valves 17 close and prevent the pressure in the feed heater from
becoming reduced. There may be two or more such separate feed
heaters arranged for different pressures, and the feed water may be
passed first through the one with the lowest pressure, and then in
succession through each with higher pressure, being in any case either
mixed with the steam or passed through tubes or passages heated by
the steam. Also the steam may be admitted into the feed heater or
heaters at periods more or less before the usual period of main exhaust,
as may be found most advantageous in practice.
In the case of compound engines the principle thus indicated may be
carried so far as to apply for heating the feed water some of the steam
after it has acted in the high-pressure cylinder 1 and without its having
acted in the low-pressure cylinder 2. For this purpose the very simple
arrangement shown by blue lines in Figures 3 and 4 may be con-
veniently adopted. It is assumed that the jacket 19 of the low-pressure
cylinder 2 is filled with steam from the intermediate receiver or low-
pressure valve casing, in other words with the steam exhausted from
the high-pressure cylinder 1. A pipe 20 with a check valve is led from
the jacket 19 and into the hot well 21, wherein it dips below the water
level, and is fitted with a large rose for dispersing the steam amongst
the water, the hot well being thus used as a feed heater.
By a third improvement applicable along with the first or second
improvement or separately the entrance into the main condenser is made
at the bottom thereof, and, by preference, so that the entering steam
blows through a shallow layer of the water of condensation, which last
is thereby rendered hotter than it otherwise would be.
A fourth improvement relates to the pumping of very hot feed water
into the boiler, which is attended with practical difficulty from the
vaporisation of the water under the diminished pressure due to the
sucking action of the pump; and it consists in using two or more
successive pumps with an air vessel between them, or preferably with
a substitute for an air vessel herein-after described as the fifth improve-
ment. Thus in the arrangement shown in Figures 1 and 2 the feed
water is led by the pipe 12 first to a centrifugal pump 22, and thence
by a pipe 23 to the usual feed pumps 24.
A fifth improvement consists in using on the delivery pipes of the
feed pumps 22, 24, and instead of air vessels which do not act satis-

page_text: factorily with hot water, either flexible metallic diaphragms, or the
arrangement shown in section in Figure 6, Sheet 1, consisting of a
plunger 25 working through a stuffing box and with a spring 26
applied externally, the object being to avoid the effects of the concussive
action of the pump's reciprocation.
The next part of the Invention relates to the working of steam
expansively through two or more cylinders in succession. One if not
the principal advantage of working steam through a number of cylinders
consists in there being a much smaller change of temperature in each
cylinder than there is in a single cylinder in which the steam is worked
to the same degree of expansion. There has, however, been consider-
able difficulty particularly with single sets of such cylinders when
starting or reversing or working very slowly, which difficulty has
greatly interfered with the otherwise advantageous extension of the
system.
By an improvement constituting the sixth of this Invention reducing
valves (various kinds of which are well known as applied to other
purposes) are fitted in connection with the second valve casing or with
each valve casing excepting the first, the reducing valve to each casing
being weighted or proportioned to admit thereto steam of the diminished
pressure suitable for working the corresponding cylinder. The reducing
valve or valves will receive the steam from the main steam pipe by a
branch or branches which may be fitted with a stop valve or valves,
whereby the steam can be shut off from the reducing valves when the
engines have not to be frequently started or reversed; or the reducing
valves may be arranged with the full-pressure steam constantly admitted
to them, but being in such case, by preference, weighted or proportioned
to admit somewhat lower pressures than those in the casings when the
engines are working regularly, so that the valves will act only when the
pressures in the casings are deficient.
The kind of reducing valve I prefer to employ is a proportional one,
that is, one arranged to supply steam of a pressure having a certain
ratio to the boiler pressure whatever the boiler pressure may be. Such
valves are shown as applied to three-cylinder compound engines in
Figure 1, and as enlarged and in vertical section in Figure 7 on Sheet 1,
and along with them similar proportional valves are shown for allowing
any excess of pressure to escape directly to the condenser. Steam from
the main steam pipe 27 has access by a branch 28 to a space 29

page_text: between a valve 30 and a piston 31.
The valve 30 opens into a space
communicating by a short branch 32 with the valve casing of the
second cylinder 2, and the other side of the piston 31 is in communica-
tion with the condenser by the pipes 33, 34, 35. The valve 30 and
piston 31 are proportioned relatively to each other to suit the intended
proportions between the pressures in the valve casing of the high-
The result
pressure cylinder 1, and in that of the next cylinder 2.
will be that whenever the steam in the latter casing gets below what it
should be the valve 30 will open and admit sufficient fresh steam to
correct the pressure.
A valve 36 and piston 37 are exposed to the
condenser pressure by the pipes 34, 35, the piston 37 having its outer
side in communication with the steam pipe 28 by a branch 38. The
valve 36 and piston 37 being suitably proportioned will correct an excess
of pressure should it occur in the valve casing of the second cylinder by
opening an escape for it to the condenser. A branch pipe 39 puts the
valve casing of the third cylinder 3 in communication with a set of
valves similar to those just described, but the steam for making up
deficiency of pressure is supplied by the branch pipe 40 in communica-
tion with the next higher valve casing, instead of from the high-pressure
steam pipe 28.
Figure 8 is a vertical section of a more compact arrangement of the
valves, which will be easily understood on comparing the reference
numerals with those in Figure 7.
The herein-before described arrangements are not adapted for certain
varieties of compound engines in which difficulties occur on starting or
reversing from the condenser vacuum not being low enough or from
there being too great a back pressure. These last-named difficulties can,
however, be overcome by appliances, Letters Patent for which I applied
for on 16th November 1871 (No. 3096).
Having thus particularly described the 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 the herein-before in part recited Letters Patent is,―
1. The applying of an adjustable valve in the entrance to the
condenser and the mixing of the water of condensation with the
exhaust steam before the latter passes that valve, as hercin-before
described.

page_text: 2. The arrangements herein-before described as constituting the second
improvement.
3. The making of the entrance to the main condenser at the bottom
thereof, as herein-before described.
4. The using of two or more successive pumps for pumping very hot
feed water, as herein-before described.
5. The applying of flexible metallic diaphragms or plungers controlled
by springs instead of air vessels upon hot water feed pipes, as herein-
before described.
6. The fitting of reducing valves in connection with the second valve
casing or each valve casing excepting the first of compound engines,
each such valve being in communication with the main steam pipe or
with the next higher valve casing, as and for the purposes herein-before
described.
In witness whercof, I, the said James Weir, have hereunto set
my hand and seal, this Nineteenth day of January, in the
year of our Lord One thousand eight hundred and seventy-.
two.
Witness,
EDMUND HUNT,
Patent Agent,
Glasgow.
JAMES WEIR. (L.S.)