IMPROVEMENTS IN APPARATUS FOR PREVENTING THE EXPLOSION OF STEAM BOILERS, FOR MEASURING THE PRESSURE OF STEAM AND OTHER FLUIDS, AND IN HEATING WATER FOR THE SUPPLY OF STEAM BOILERS
Year: 1854

page_text: LETTERS PATENT to Joseph Hulme, of the City of Manchester, Engineer,
for the Invention of "IMPROVEMENTS IN APPARATUS FOR PREVENTING THE
EXPLOSION OF STEAM BOILERS, FOR MEASURING THE PRESSURE OF STEAM
AND OTHER FLUIDS, AND IN HEATING WATER FOR THE SUPPLY OF STEAM
BOILERS."
Sealed the 6th February 1855, and dated the 8th August 1854.
PROVISIONAL SPECIFICATION left by the said Joseph Hulme at the
Office of the Commissioners of Patents, with his Petition, on the 8th
August 1854.
I, JOSEPH HULME, of the City of Manchester, Engineer, do hereby declare
the nature of the said Invention for "IMPROVEMENTS IN APPARATUS FOR PRE-
VENTING THE EXPLOSION OF STEAM BOILERS, FOR MEASURING THE PRESSURE OF
STEAM AND OTHER FLUIDS, AND IN HEATING WATER FOR THE SUPPLY OF STEAM
BOILERS," to be as follows:-
The first of my improvements consists in preventing the explosion of a steam
boiler, by attaching thereto a disk of sheet metal that will explode or burst at
a given pressure; for instance, if a boiler is employed for raising steam to
forty pounds pressure, I attach thereto a disk of six inches, or other suitable
diameter, which disk shall be capable of resisting a pressure of forty-one or
more pounds to the square inch. By this means, if the steam in the boiler is

page_text: allowed to become sufficiently powerful, it bursts the disk and allows the steam
to blow off. In preparing these disks, I propose first to test the metal by
suitable chemical agents, and then to test the strength thereof by steam
power or mechanical agents. My improvements in apparatus for measuring
the pressure of steam and other fluids consist in a piston, against the upper
surface of which the fluid acts. This piston fits in a cylinder and has a rod
passing through a stuffing box. Near the upper end of the rod is a slot,
through which passes one end a double lever; whose fulcrum is attached to the
boiler or to the said cylinder, but is capable of being moved nearer to or
further from the centre of the piston rod; a balance weight is suspended to
the outer end of the double lever. When this apparatus is applied to a boiler
to ascertain the pressure of the steam within it, the distance of the fulcrum to
the centre of the piston is adjusted until the action of the steam on the piston
balances the weight; the weight may also be applied to the piston rod,
thereby dispensing with the lever. My improvements in heating water for
the supply of steam boilers consist in putting the water to be heated in an
open shallow vessel of thin sheet metal; this vessel is heated by a fire, and the
water when heated is pumped into the boiler in the ordinary manner.
soon as the boiler has received a sufficient supply of hot water, the pump is
stopped and the shallow vessel is raised off the fire.
As
SPECIFICATION in pursuance of the conditions of the Letters Patent, filed
by the said Joseph Hulme in the Great Seal Patent Office on the 7th
February 1855.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, JOSEPH
HULME, of the City of Manchester, Engineer, send greeting.
.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her Letters
Patent, bearing date the Eighth day of August,. in the year of our Lord
One thousand eight hundred and fifty-four, in the eighteenth year of
Her reign, did, for Herself, Her heirs and successors, give and grant unto
me, the said Joseph Hulme, Her special license that I, the said Joseph
Hulme, my executors, administrators, and assigns, or such others as I,
the said Joseph Hulme, 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

page_text: "IMPROVEMENTS IN APPARATUS FOR PREVENTING THE EXPLOSION OP STEAM
BOILERS, FOR MEASURING THE PRESSURE OF STEAM AND OTHER FLUIDS, AND IN
HEATING WATER FOR THE SUPPLY OF STEAM BOILERS," upon the condition
(amongst others) that I, the said Joseph Hulme, 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 Joseph Hulme, 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, that is to say:
The nature of my Invention of improvements in apparatus for preventing
the explosion of steam boilers consists in the application of a sheet metal
disk, one surface of which is exposed to the action of the steam in the boiler,
and the other to the atmosphere, which disk explodes or bursts when the steam
attains too great a pressure.
Secondly, in certain improved apparatus for measuring the pressure of steam
and other fluids, consisting of a piston and weighted lever, whereby the actual
pressure of the fluid is determined.
And, lastly, my improvements in heating the water for the supply of steam
boilers consists in suspending an open shallow vessel over a fire, into which
vessel the water to be heated is supplied; this water, when sufficiently heated,
is pumped into the boiler in the ordinary manner, and when a sufficient
quantity of water has been pumped into the boiler, the vessel may be raised off
its seating until more is required.
Having thus stated the nature of my Invention, I will proceed to describe
the manner of performing the same; reference being had to the accompanying
Drawings, and to the letters and figures marked thereon.
DESCRIPTION OF THE DRAWINGS.
Figure 1 is a vertical section through my improved apparatus for pre-
venting the explosion of steam boilers; Figure 2 is an elevation, and Figure 3
a plan, of the same. a is a box attached to the steam boiler or to the feed
pipe of a steam engine; b is a thin sheet metal disk, bolted between the
flanche of the box a and the annular flanche c, to which is attached or cast
the cross piece d; this cross piece supports the button e, which bears on the
centre of the disk b, to prevent it rising when the pressure of the steam

page_text: becomes sufficiently great to influence the centre of the disk. The thickness
of the disk is determined according to the pressure required on the boiler to
which my improved apparatus is applied; for instance, if a boiler be employed
for raising steam of forty pounds pressure on the square inch, the disk should
be capable of resisting a pressure of about forty-two pounds on the square
inch; consequently, if the steam in the boiler is allowed to acquire sufficient
force, the steam bursts or explodes the disk, and then makes its escape through
the cover c', or into an off-pipe. I propose to place the apparatus above
described in a case, to which no one but the owner or other competent person
has access, thereby to a great extent preventing the explosions of steam boilers
caused by excess of pressure. The notches, marked f in the flanche c and
flanche of the box a, are made to enable the thickness of the disk b to be
guaged without taking the apparatus to pieces. In preparing these disks,
which I prefer to make of wrought iron, I propose first to test the metal by
suitable chemical agents, in order to ascertain the component parts of the
metal, and then to test the strength thereof by steam power or by mechanical
agents.
Figure 4 represents an elevation of my improvements in apparatus for
measuring the pressure of steam and other fluids. g is part of a boiler; his
a short cylinder, connected to the boiler by the stop-cock i, and supported
by the bracket j; within the cylinder h is a piston k, fixed to the rod I, which
passes above through a stufling box, and is furnished below with a hook m.
The rod is connected above by the link o to the lever n, whose fulcrum is
at n', and the link 2 connects the lever n to the weighted lever P, whose
fulcrum is at p'. The mode of operation is as follows:-When the stop-
cock i is opened to admit steam to the cylinder h, the weight is moved by tho
attendant along the lever p, until the pressure of the steam on the piston k is
exactly balanced; the stop-cock i is then closed, and weights are hung to the
hook m until the weight on the lever p is balanced; consequently, if the are
of the piston k be four inches, and one hundred pounds are required to
counterbalance the weight on the lever p, it is evident that the steam in the
boiler is at twenty-five pounds pressure.
Figure 5 represents a modification of the above-described improved appa-
ratus for measuring the pressure of fluids. This combination is suitable for
measuring low pressure steam, and as many of the parts are similar to those
shewn in Figure 4, they are marked with similar letters of reference. In the
present arrangement the compound levers are dispensed with, and the weight
is attached to a prolongation of the lever n. The mode of operation for ascer-
taining the pressure of the steam is precisely similar to that above described.

page_text: My improvements in apparatus for heating water for the supply of steam
boilers is shewn in section in Figure 6, in which r is a shallow open vessel,
supported on the seating s, and suspended to the levert, to the other end of
which is suspended the rod u. This rod has a hook at the lower end, and to it
is attached one end of a chain or cord v, the other end of which is attached
to the elbow lever w. x is a chain or cord connecting the elbow lever w with
the floater of the boiler to which this improved heating apparatus is applied.
The water to be heated is supplied through the pipe y, and is a spout for
conveying the heated water from the vessel r to the cistern, from which it is
pumped into the boiler in the ordinary manner. When the level of the
water in the boiler is sufficiently high the pumping is stopped; and the floater,
acting on the cord or chain a, draws the rod u into a vertical position, thereby
bringing the hook at its lower end under the crank A, which is constantly
revolving in the direction of the arrow; by this means the rod is drawn down
and the vessel r raised off its seating, where it remains until more water is
required in the boiler, when the vessel is again brought on its seating and
the pump set to work.
Having thus described the nature of my Invention, and the manner of per-
forming the same, I wish it to be understood that I do not confine myself to
the exact details described; but what I claim is,―
First, the sheet metal disk marked b, when used in the manner and for the
purpose described, in reference to Figures 1, 2, and 3.
Secondly, the improved apparatus shewn and described, in reference to
Figures 4 and 5, for measuring the pressure of steam and other fluids.
And, lastly, the improved apparatus for heating water for the supply of steam
boilers, as shewn and described in reference to Figuro 6.
In witness whereof, I, the said Joseph Hulme, have hereunto set my
hand and seal, this Sixth day of February, One thousand eight hundred
Witness to the signature of Joseph Hulme,
H. B. BARLOW,
Patent Agent,
Manchester.
JOSEPH HULME. (L.S.)