IMPROVEMENTS IN STEAM BOILERS
Year: 1874

page_text: LETTERS PATENT to George Weir and James Weir, both of Glasgow,
in the County of Lanark, North Britain, Engineers; for the Inven
tion of "IMPROVEMENTS IN STEAM BOILERS,"
Sealed the 28th May 1875, and dated the 17th December 1874.
"
PROVISIONAL SPECIFICATION left by the said George Weir and
James Weir at the Office of the Commissioners of Patents, with
their Petition; on the 17th December 1874.
ነ
We, GEORGE WEIR and JAMES WEIR, both of Glasgow, in the
County of Lanark, North Britain, Engineers, do hereby declare the
nature of the said Invention. for “IMPROVEMENTS IN STEAK BOILERS,”.
be as follows, that is to say :-
This Invention has for its objects to prevent injury to steam boilers
from unequal expansion when being first heated;, and generally to
secure greater efficiency and uniformity of action by improved means. of
causing circulation of the water therein.
Price 8d1

page_text: The Invention will be very advantageous to marine boilers to whic
it will in general be more conveniently although not exclusively
applicable.
In boilers with internal fires, or heated otherwise than on their under
sides, the water in the bottom of the boilers remains cold for a long time
after lighting the fires, and the upper parts of the boilers become con-
siderably heated and expanded before the bottom parts, so that very
injurious strains are produced between the different parts.
By the present Invention the unequal heating is prevented by making
the water circulate from the time of lighting the fires, the apparatus for
this purpose consisting, according to one modification, of one or more
nozzles fixed in suitable positions at the lower parts of the boiler and
supplied with steam from a separate boiler. On board ship it will
generally be convenient to obtain the requisite steam from a small
donkey boiler or from a boiler of a steam winch. Inside the main boiler
there is fixed over the steam nozzle a casing with a second larger nozzle,
and with perforations to admit water between the two nozzles, whilst
keeping back any obstructing matters, an arrangement which will induce
a stronger current accompanied by less noise. In the pipe leading to
the nozzle there is a check valve which closes on the steam getting up
in the boiler, and a screw spindle may be applied in connection with this
valve to make it serve as a stop valve also. When the boilers are steaming,
all or part of the feed water may be passed through the nozzle so as to
promote circulation.
Where there are several boilers together steam can be first got up in
one, and be used for producing circulation in the others before steam
is up in them; or in one of a series of boilers steam may be maintained
at a higher pressure than in the others and be employed in continuously
keeping up circulation in the others.
•

page_text: . 4
WHEREAS Her most Excellent Majesty Queen Victoria, by Her
Letters Patent, bearing date the Seventeenth day of December, in the
year of our Lord One thousand eight hundred and seventy-four, in the
thirty-eighth year of Her reign, did, for Herself, Her heirs and suc-
cessors, give and grant unto us, the said George Weir and James Weir,
Her special licence, that we, the said George Weir and James Weir,
our executors, administrators, and assigns, or such others as we, the
said George Weir and James Weir, our 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 STEAM
BOILER upon the condition (amongst others) that we, the said. George
Weir and James Weir, our executors or administrators, by an
instrument in writing under our, or their, or one of their hands and
seals, should particularly describe and ascertain the nature of the said
Invention, and in what manner 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 immediately after the date of the said Letters
Patent.
'
"
"
NOW KNOW YE, that we, the said. George Weir and James Weir,
do hereby declare the nature of our 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:-
Our said Invention has for its objects to prevent injury to steam boilers
from unequal expansion when being first heated, and generally to secure
greater efficiency and uniformity of action by improved means of causing
circulation of the water therein.
Our Invention will be very advantageous to marine boilers to which
it will in general be more conveniently although not exclusively
applicable.
'
In boilers with internal fires, or which are heated otherwise than on
their under sides, the water in the bottom of the boilers remains cold
for a long time after lighting the fires, and the upper parts of the boilers

page_text: become considerably heated and expanded before the bottom parts,
So that very injurious strains are produced between the different parts.
It is generally admitted by engineers and others connected with the
working of steam ships, that the unequal expansion of the metal of the
boiler whilst raising steam is the cause of the leakage which very
commonly takes place at the landings and rivets in the bottom of the
boiler shell, and about the furnace landings below the fire-bars.
By our present Invention however the unequal heating of the boilers
is prevented by making the water circulate in an effective manner from
the time of lighting the fires, the apparatus for this purpose consisting,
according to one modification, of one or more nozzles fixed in suitable
positions at the lower parts of the boiler and supplied with steam from
a separate boiler. On board ship it will generally be convenient to
obtain the requisite steam from a small donkey boiler, or from the boiler
of a steam winch.
And in order that our said Invention and the manner of performing
the same may be properly understood, we hereunto append a Sheet
of explanatory Drawings, to be herein-after referred to, and representing
various modifications of apparatus which we propose employing. In these
Drawings the same reference numerals are used to mark the same or like
parts wherever they are repeated.
Figure 1 of the Drawings is a section of a simple steam nozzle 4,
and Figure 2 is a section of a compound nozzle which we prefer and
which we find very suitable and efficacious in practice.
Figure 3 is a section of a compound induction nozzle combined with
a number of distributing nozzles.
Figure 4 is a transverse vertical section of a cylindrical boiler with
three internal furnaces 1, 2, 3, constructed in cylindrical flues.
In the arrangement shown in Figures 2 and 4, the steam first enters
a primary nozzle 4 formed at right angles to an inlet pipe branch 5 fixed
inside the boiler shell 6. In front of and covering the primary nozzle 4
there is a second larger one 7, formed with a grating 8 through which
some of the water of the boiler enters to combine with the steam jet; and
in a similar way a third still larger nozzle 9 is fixed in front of the second
one 7, and more water of the boiler has access through a grating 10 to
this third nozzle. The apparatus will work sufficiently well with only

page_text: two nozzles 4 and 7 or even with only a single one 4, as shown in
Figure 1, but with the three a stronger current is produced with less noise
and tremor.. Outside the boiler in the pipe or fitting 11, connecting the
steam pipe 12 with the boiler, there is arranged a check valve 13 which
closes on the pressure due to steam formed in the boiler, eventually
becoming greater than that in the steam pipe 12; and a screw spindle 14
working through a stuffing-box is applied in connection with this valve
13 to make it serve as a stop valve also. When the boiler is steaming,
all or part of the feed water may be passed through the nozzle 4, or as
we prefer, through a separate simpler nozzle 15 fixed at a higher or more
convenient part of the boiler. This nozzle 15 may either be uncovered
or it may be encircled, as shown by the upper enlarged end 16 of a pipe
17, leading from the lowest part of the boiler, so that the inductive
action of the jet from the nozzle 15 may cause the water to pass up
the pipe 17 from the bottom of the boiler. Where extreme simplicity
is desired the steam inlet may have a stop-cock 18, as shown in

page_text: box, and outside of the boiler is fitted with a handle 2 and pulle y
26, for being worked directly by hand or by means of a cord.
Where there are several boilers together steam can be first got up in
one, and be used for producing circulation in the others before steam
is up in them; or in one of a series of boilers steam may be main-
tained at a higher pressure than in the others, and be employed in con-
tinuously keeping up circulation in the others, even after steam is up in
them, as well as during the time it is being got up.
Having thus particularly described our said Invention and the manner
of performing the same, we have to state that we do not restrict our-
selves to the precise details herein described and delineated, and that we
disclaim the imperfect mode that has been tried of attaining our
objects by withdrawing water by means of a pump from one part of a
boiler and reintroducing it at another part without current inducing
nozzles; but that what we believe to be novel and original and claim as
the Invention secured to us by the herein-before in part recited Letters
Patent is, the causing of circulation of the water in steam boilers when
being heated up from a cold condition by means of jets of steam or
water suitably directed by nozzles fitted inside the boiler as herein-
before described.
In witness whereof, I, the said James Weir, on behalf of the said
George Weir, and myself, have hereunto set my hand and seal,
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this Fifteenth day of June, in the year of our Lord One thousand
eight hundred and seventy-five.
Witness,
EDMUND HUNT,
I
Patent Agent,
Glasgow.
JAMES WEIR. (L.s.)