IMPROVEMENTS IN THE
Year: 1855

page_text: LETTERS PATENT to Hugh Greaves, of New Palace Yard, in the City of
Westminster, Civil Engineer, for the Invention of "IMPROVEMENTS IN THE
"
Sealed the 25th March 1856, and dated the 13th October 1855.
PROVISIONAL SPECIFICATION left by the said Hugh Greaves at the
Office of the Commissioners of Patents, with his Petition, on the 13th
October 1855.
I, HUGH GREAVES, of New Palace Yard, in the City of Westminster, Civil
Engineer, do hereby declare the nature of the said Invention for "IMPROVE-
MENTS IN THE CONSTRUCTION OF STEAM BOILERS" to be as follows:-
This Invention relates principally to the construction of steam boilers of the
form usually adapted to locomotive steam engines, and commonly known'as
"multitubular boilers," and is designed for the purpose of 'allowing or producing
a more perfect and uniform circulation of the water and steam in such boilers.
In carrying out this Invention, I connect the fire box side of the tube plate,
by means of a pipe or pipes, with the inside of the roof or crown of the inner
shell of the fire box, and in some cases I apply similar pipes on all sides of the
fire box, so as to allow of still better circulation. I likewise connect by a pipe
that part of the water space which is below the fire door to that part of the
water space which is above the said door. This pipe may be placed either

page_text: inside or outside of the fire box, or it may be carried up through the water
space; I also employ a conical tubular column or tubes passing through the
fire, being suspended from the crown or cover of the inside of the fire box, and
provided with a blow-off cock at the bottom, and a circulating plate or tube
inside the said pipe. The circulating pipe or pipes from the side or sides of
the fire box may be connected either with the column, above mentioned, or with
the crown of the fire box; or a pipe may be fixed at about the centre of the
tubes in the barrel part of the boiler, so as to carry the saturated steam and
water to the surface. One of the central tubes-may be connected with one of
the circulating pipes above named, and pierced with small holes for the
admission of water, and carried to the centre (longitudinally) of the tubes, so
as to assimilate the temperature of the water in the barrel of the boiler with
that at the fire box end of the boiler. The feed water with which the boiler
is supplied may be thrown direct into the vertical column. A circulating pipe
may also be taken from the centre or any other part of the tube plate at the
smoke box end of the boiler, passing through the smoke box, and communi-
cating, with the steam space above the water. The method which I employ
of connecting the circulating tubes with the boiler plate is by cutting a screw
thread externally upon the end of the said pipes, and passing a nut.or screwed
collar thereon, which nut or collar is also provided with an external thread, by
which it is screwed into the boiler plate. I likewise connect the lower part of
the barrel of the boiler by pipes to the fire box, or the tubes may pass through
the smoke box, and communicate with the steam space in the upper part..
SPECIFICATION in pursuance of the conditions of the Letters Patent, filed
by the said Hugh Greaves in the Great Seal Patent Office on the 25
12th April 1856.-
“་
TO ALL TO WHOM, THESE PRESENTS SHALL COME, I, HUGH
GREAVES, of, New Palace. Yard, inthe, City of Westminster, Civil Engineer,
sendigreeting.ai matatawa
WHEREAS: Her mosto Excellent Majesty Queen Victoria, by Her Letters 30
Patent; bearingodate the. Thirteenth day of October, in the year of our
Lord One thousand eight hundred and fifty-five, in the nineteenth year of
Her, reign; did;..for Herself, Her heirs and successors, give and grant: unto
me, theirsaid Hugh Greaves, Her-special license that I, the said Hugh
Greaves, my executors;; administrators, and assigns, or such other's as I, the 35

page_text: said Hugh Greaves, my executors, administrators, or assigns, should at any
time agree with, and no others, from time to time and at all times there-
after 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 "IMPROVE-
MENTS IN THE CONSTRUCTION OF STEAM BOILERS," upon the condition (amongst
others) that I, the 'said Hugh Greaves, by an instrument in writing under
my hand and seal, 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 I, the said Hugh Greaves, 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,
reference being had to the accompanying Drawings, and to the letters and
figures marked thereon, that is to say:-
7. My said Invention relates principally to the construction of steam boilers of
the form usually adapted to locomotive steam engines; and commonly known as
"multitubular boilers," and is designed for the purpose of allowing or pro-
ducing a more perfect and uniform circulation of the water and steam'in such
.boilers.
1-1
:
1. 225
In carrying out this Invention, I connect the fire box of the tube plate
by means of a pipe or pipes with the inside of the roof or crown of the inner
shell of the fire box, and in some cases' I 'apply similar pipes on all sides of the
fire box, so as to allow of still better circulation; I likewise connect by a pipe
that part of the water space which is below the fire door to that part of the
water space which is above the said door. This pipe may be placed either
inside or outside of the fire box, or it may be carried up through the water
space, or the fire door ring, may be made of cast malleable iron, and' cast
hollow to act as a tube: The circulating pipes I likewise propose to make of
cast malleable iron, in preference to other metals. I also employ' a' conical
tubular column or tubes passing through the fire, being suspended from the
crown. or cover of the inside of the fire box, and provided with a blow-off cock
at the bottom, and a circulating tube inside the said pipe. The circulating pipe
or pipes from the side or sides of the fire box may be connected either with
the column above mentioned or with the the crown of the fire box: A pipe is
fixed at about the centre of the tubes in the barrel part of the boiler; so as to
carry the saturated steam and water to the surface. One of the central tubes
may be connected with one of the circulating pipes above named, and pierced

page_text: with small holes for the admission of water, and carried to the centre (longi-
tudinally) of the tubes, so as to assimilate the temperature of the water in the
barrel of the boiler with that at the fire box end of the boiler. The feed water
with which the boiler is supplied may be thrown direct into the vertical
column. A circulating pipe may also be, taken from the centre or any other.
part of the tube plate at the smoke box end of the boiler, passing through.the
smoke box, and communicating with the steam space above the water. The
method which I employ of connecting the circulating tubes.with the boiler
plate is by cutting a screw thread externally upon the end of the said pipes
and passing a nut or screwed collar thereon, which nut or collar is also
provided with an external thread, by which it is screwed into the boiler plate.
I likewise connect the lower part of the barrel of the boiler by pipes.to.the.fire
box, or the tubes may pass through the smoke box, and, communicate with the
steam space in the upper part.
And in order that my said Invention may be fully understood, I shall now.
proceed more particularly to describe the same, and for that purpose I shall
refer to the several Figures on the Sheet of Drawings hereunto annexed,
the same letters of reference indicating corresponding parts throughout the
Figures.
Figure 1 of the Drawings represents a longitudinal vertical section of my
improved steam boiler; and Figure 2 is a corresponding transverse section of
the same, taken through the fire box.
A, A, are a series of pipes which connect the upper part of the inner
shell of the fire box B to the roof thereof, and serve, by producing a better
circulation of the globules of steam as fast as they are formed, to allow of their
easily rising to the surface. By this means the lodgment of steam, which it
has been found in practice takes place at or about the part or level C of the
fire box, is prevented, and the consequent burning of the fire box, arising by
reason of the steam (which is a non-conductor) interposing in place of the
water, is obviated. Any convenient number of these pipes may be used, and
they may be arranged round the two sides and front of the fire box; one or
more similar pipes D may also be arranged so as to connect that portion of
the water space below the fire door E with the portion above it, or with the
roof of the fire box. This pipe or pipes may be conducted either inside or out-
side the fire box, or through the water space, as found most desirable.
A central pipe or tube F extends from one tube plate to the other, and is
perforated with holes or slots, in order to convey the water which is heated
and the steam generated amongst the tubes G to the surface by the pipe H,
which is placed inside the fire box, and connects one end of the tube F with

page_text: the crown of the fire box. In place of having .a+ single perforated pipe of a
larger size than the ordinary tubes, two or more perforated pipes may be
employed of the same dimensions as the rest of the tubes. A pipe I placed in
the smoke box connects that end of the perforated pipe with the surface. One
or more, circulating pipes K.are.employed for connecting the lower portion of
the fire box.with the bottom of the main barrel of the boiler, for the purpose
of affording a free.circulation of the water and globules of steam generated in
the lower portion. of the water space immediately behind the back of the fire
box. By this means the tube plate and the ends of the tubes near the tube
plate. are relieved from a great portion of the steam, which otherwise in the
ordinary locomotive engine boilers ascends in contact with the tube plate, and
by interposing a film of steam or non-conductor to the tube plate.in place of
water, which is a conductor of heat, causes the rapid deterioration of the tube
plate. L is a pipe or slightly conical tube, suspended from the roof of the fire
box, and having an internal tube M inserted therein. The arrows in these
pipes or tubes, as well as in those herein-before referred to, indicate the direc-
tion of the circulating currents. Pipes or tubes may also, if found desirable,
be connected with the conical tube, and the sides of the fire box, or with the
front and back ends of the same. A blow-off cock N may be fitted on to the
bottom of the conical tube L.
The internal pipe M, which is placed in the centre of the tube L, and con-
nected thereto, serves to carry the water from the surface, and to keep up a
constant circulation. The feed water, when found desirable, may be forced
into the pipe L before entering the body of the boiler, by which means it will
become considerably heated before being actually brought in contact with the
water in the boiler.
The detail, Figure 3, represents on a larger scale the mode I adopt for
securing the several circulating tubes to the fire box and boiler plate. I solder
on to each end of the tube to be fitted a screwed collar a, or a screw thread
may be cut on the end of the tube itself, and on to this collar or screw
thread is passed a nut b, which is screwed internally and externally. The
external thread of the nut screws into a hole tapped into the plate c, to
which the end of the tube is to be fitted, whilst the internal screw thread is
screwed over the external thread on the collar, which is soldered or otherwise
secured on to the end of the pipe to be fitted. By this means a simple mode
of attachment is obtained, producing also a perfectly steam and water tight
joint.
Having now described and particularly ascertained the nature of my said
Invention, and the manner in which the same is or may be used or carried

page_text: into effect, I would observe, in conclusion, that I do not confine or restrict
myself to the precise details. or. arrangements which I have had occasion to
describe or refer to, as, many variations may be made therefrom without
deviating from the principles or, main features of my said Invention; but what
I consider, to be novel and original, and therefore claim as the Invention
secured to me by the herein-before in part recited Letters Patent, is,-.
First,, the application and use of circulating pipes.or tubes in locomotive or
multitubular boilers, for the purpose of producing a better circulation of the
water and steam contained therein, as herein-before described, and illustrated
by the Drawings
**
Second, the peculiar mode of attaching or securing the ends of the circulat-
ing, tubes, as herein-before described, and illustrated by Figure 3 of the
Drawings
In witness whereof, 'I, the said Hugh Greaves, have hereunto set my hand
and seal, the Twelfth day of April, One thousand eight hundred and
fifty-six.
5
Signed by the said 'Hugh Greaves, in the
presence of
*
J. HENRY JOHNSON,
47, Lincoln's Inn Fields.
3..
"H. GREAVES. (L.B.)