IMPROVEMENTS IN SETTING BOILERS AND IN SAFETY VALVES FOR THE SAME."
Year: 1867

page_text: LETTERS PATENT to William Henry Parsons, Engineer, of Port Tennant
Copper Works, Swansea, in the County of Glamorgan, for the Invention
of "IMPROVEMENTS IN SETTING BOILERS AND IN SAFETY VALVES FOR THE
SAME."
PROVISIONAL SPECIFICATION left by the said William Henry Parsons
at the Office of the Commissioners of Patents, with his Petition, on the
18th March 1867.
I, WILLIAM HENRY PARSONS, Engineer, of Port Tennant Copper Works,
Swansea, in the County of Glamorgan, do hereby declare the nature of the
said Invention for "IMPROVEMENTS IN SETTING BOILERS, AND IN SAFETY VALVES
POR THE SAME," to be as follows:-
This Invention has for its object improvements in setting boilers, and in
safety valves for the same. Boilers which are set in brickwork in the
ordinary way are very liable to corrosion at and about the points where the
brickwork comes in contact with them.

page_text: Now according to my Invention in place of setting boilers on brickwork I
support them on metal rollers mounted in frames and set at suitable distances
apart. The arrangement is more especially applicable to cylindrical boilers
fired internally. I set the frames, say, at about six or eight feet the one
from the other, and each frame carries two rollers, one on each side of the
centre line of the boiler, and the rollers are so formed as to bear evenly on the
curved surface of the boiler.
In constructing safety valves according to my Invention I form the valve
of a mushroom-like form, the stem enters into the boiler through the passage
to which the valve is fitted, and has the weight suspended from it within the
boiler around the root of the stem, the valve is made to fit its seating whilst
a considerable portion of the head overhangs all round. By this construction
the valve is caused to give a very free escape to the steam as soon as the
pressure to which it is weighted is attained.
SPECIFICATION in pursuance of the conditions of the Letters Patent, filed
by the said William Henry Parsons in the Great Seal Patent Office,
on the 17th September 1867.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, WILLIAM
HENRY PARSONS, Engineer, of Port Tennant Copper Works, Swansea, in the
County of Glamorgan, send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her Letters
Patent, bearing date the Eighteenth day of March, in the year of our Lord
One thousand eight hundred and sixty-seven, in the thirtieth year of Her
reign, did, for Herself, Her heirs and successors, give and grant unto me,
the said William Henry Parsons, Her special licence that I, the said William
Henry Parsons, my executors, administrators, and assigns, or such others as
1, the said William Henry Parsons, 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 "IMPROVE-
MENTS IN SETTING BOILERS, AND, IN SAFETY VALVES FOR THE SAME," upon the
condition (amongst others) that I, the said William Henry Parsons, my
executors or administrators, by an instrument in writing under my, or their,

page_text: 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 I, the said William Henry Parsons, do hereby
declare the nature of the said Invention, and in what manner the same is
to be performed, to be particularly described and ascertained in and by the
following statement thereof, that is to say :-
This Invention has for its object improvements in setting boilers, and in
safety valves for the same. Boilers which are set in brickwork in the ordinary
way are very liable to corrosion at and about the points where the brickwork
comes in contact with them.
Now according to my Invention in place of setting the boilers directly on
brickwork I support them on rollers according to the arrangement I prefer.
I set up cast-iron frames, say, at about six or eight feet the one from the
other, and each frame carries two rollers, one on each side of the centre line
of the boiler; and the rollers are so formed as to bear evenly on the curved
surface of the boiler.
In constructing safety valves according to my Invention I form the valve
of a mushroom-like form, the stem enters into the boiler through the passage
to which the valve is fitted, and has the weight suspended from it within the
boiler. Around the root of the stem the valve is made to fit its seating,
whilst a considerable portion of the head overhangs all round. By this con-
struction the valve is caused to give a very free escape to the steam as soon as
the pressure to which it is weighted is attained. It is not essential that the
valve should have a stem descending down into the boiler as the weight or.
pressure may be otherwise applied to the valve.
And in order that my said Invention may be most fully understood and
readily carried into effect I will proceed to describe the Drawings hereunto
annexed.

page_text: either side, and the boiler bears on the rollers, as is shown. When the
boiler expands and contracts it is able to move freely, and has no tendency
to derange the brickwork, and the boiler is not able to corrode externally, not
being in contact with. brickwork. The frames c, c, and rollers d, d, are
shown separately at Figures 3.
A modification of the arrangement is shown at Figures 4 and 5, Figure 4
being a longitudinal section, and Figure 5 a transverse section; here the cast-iron
frames c are bolted to the boiler, and the frames bear on the rollers at their
two ends, the rollers being supported on flat plates on the side walls of the
setting. The frames and rollers which are used in this arrangement are
shown separately to a larger scale at Figures 6.
A safety valve constructed according to my Invention is shown at Figure 7,
and a vertical section of the same valve is shown at Figure 8.
a, a, is a
casting on which the valve seat is formed; it is fitted to an opening formed in
the boiler, and firmly bolted down by its flange a¹, so as to make a steam-
tight joint. 6 is the valve; 6', a stem fixed to it and projecting down into the
boiler, it has the weight 6 suspended from it; and is the overhanging head
of the valve on which the steam acts as soon as it begins to escape to assist
in lifting the valve to allow the steam to blow off freely.
Figure 9 is a side view, and Figure 10 a vertical section of a safety valve
to which a spring is applied in lieu of a weight. a is the casting with the
valve seat upon it as before; b is the valve; the stem of the valve b¹ is fixed
in a bridge piece at the bottom of the casting a, it passes up freely through a
hole in the centre of the valve, and receives the coiled spring 6 which presses
on the upper surface of the valve with a force which is capable of some
adjustment by means of the screw nut 6. At the top of the valve is a steam-
tight cover to prevent the escape of steam by the passage through which
the stem 6 passes.
Figure 11 is a side view, and Figure 12 a vertical section of an arrange-
ment in which the stein 6¹ projects upwards from the valve, and has suspended
from it the annular weights 6 which surround the casting a.
Figure 13 is a side view, and Figure 14 a back view, of an arrangement in
which the action of the steam in lifting the valve when it has once been raised
from its seat is aided by a lever. In this arrangement also the stem b¹ of the
valve projects upwards; it is jointed to the bell-crank lever c, which has a fixed
fulcrum at d; the weight is suspended from the upper arm of the lever.
Valves arranged according to my Invention are more especially applicable
as second valves, which are not required to operate until the pressure has

page_text: been allowed to rise to an undue extent, and are then required to relieve the
pressure as rapidly as possible.
In witness whereof, I, the said William Henry Parsons, have hereunto
set my hand and seal, this Sixth day of September, in the year of our
Lord One thousand eight hundred and sixty-seven.
WILLIAM HENRY PARSONS. (L.s.)