A New and Improved Safety Valve for Heating and Domestic Boilers, such as Kitchen Boilers and the like
Year: 1894

page_text: Date of Application, 2nd Mar., 1894
Complete Specification Left, 20th Apr., 1894-Accepted, 25th May, 1894
PROVISIONAL SPECIFICATION.
A New and Improved Safety Valve for Heating and Domestic
Boilers, such as Kitchen Boilers and the like.
I, WILLIAM PARKER, of Ashdune, Catford Hill, in the County of Kent,
Engineer, do hereby declare the nature of this invention to be as follows:-
:-
My invention has for its object the production of a safety valve of cheap and simple
construction not liable to derangement and which will afford immediate relief in
the event of any undue increase of pressure in a boiler designed for heating water
rather than to generate steam as for example a kitchen boiler or a green-house
boiler, or boilers for heating public buildings.
My safety valve comprises a vessel with closed top and with a tubular branch or
passage opening into the vessel and adapted to be connected to a boiler so as to
place the interior of the boiler in communication with the interior of the covered
vessel.
From the lower part of the covered vessel a pipe or passage leads to another
pipe or passage extending in an upward direction to a height depending upon the
maximum pressure that is to be permitted to accrue in the boiler.
The extremity of the pipe or passage has a downward direction and enters or has
or may have below it a vessel into which it can discharge.
The closed vessel and the pipe or passage communicating with its lower part are
charged up to a suitable level with mercury; so that if then an undue rise of
pressure in the boiler occurs the fluid (steam or water) in the boiler will press on
the surface of the mercury in the closed vessel and force it down raising the level
of the mercury in the pipe or passage, and if the pressure be greater than that the
apparatus is adapted to resist, the mercury will be forced out of the pipe or passage
into the vessel placed below the higher open end of the pipe or passage thus at
once allowing the fluid contents of the boiler to freely escape, and relieve the
boiler of pressure whilst the mercury can afterwards be replaced in the closed
vessel and pipe or passage for re-use.
As will be evident a safety valve such as above described may be variously
modified as respects the details of construction.
Dated this 2nd day of March 1894.
COMPLETE SPECIFICATION.
A New and Improved Safety Valve for Heating and Domestic
Boilers, such as Kitchen Boilers and the like.
I, WILLIAM PARKER, of Ashdune, Catford Hill, in the County of Kent,
Engineer, do hereby declare the nature of this invention and in what manner the
same is to be performed to be particularly described and ascertained in and by the
following statement :-
My invention has for its object the production of a safety valve of cheap and simple
construction not liable to derangement and which will afford immediate relief in
the event of any undue increase of pressure in a boiler designed for heating water

page_text: rather than to generate steam as for example a kitchen boiler or a greenhouse
boiler, or boilers for heating public buildings.
My safety valve comprises a vessel with closed top and with a tubular branch or
passage opening into the vessel and adapted to be connected to a boiler so as to
place the interior of the boiler in communication with the interior of the covered
vessel.
From the lower part of the covered vessel a pipe or passage leads to another
pipe or passage extending in an upward direction to a height depending upon the
maximum pressure that is to be permitted to accrue in the boiler.
The extremity of the pipe or passage has a downward direction and enters or
has or may have below it a vessel into which it can discharge.
The closed vessel and the pipe or passage communicating with its lower part are
charged up to a suitable level with mercury; so that if then an undue rise of
pressure in the boiler occurs the fluid (steam or water) in the boiler will press on
the surface of the mercury in the closed vessel and force it down, raising the level
of the mercury in the pipe or passage, and if the pressure be greater than that the
apparatus is adapted to resist, the mercury will be forced out of the pipe or passage
into the vessel placed below the higher open end of the pipe or passage, thus at
once allowing the fluid contents of the boiler to freely escape, and relieving the
boiler of pressure, whilst the mercury can afterwards be replaced in the closed
vessel and pipe or passage for re-use.
As will be evident a safety valve such as above described may be variously
modified as respects the details of construction. A convenient form is shown in
the appended vertical sectional drawing in which A. is a saddle boiler with tank B
above and circulating pipes C and D as well understood. To the boiler A is shown
applied my improved safety valve whereof a is the mercury-containing vessel, with
closed top b, branch c connected to the boiler, so as to place the interior of the
boiler in communication with the vessel a pipe d leading from the lower part of the
vessel and connecting it with the upright pipe e, the height of which will depend
upon the maximum pressure that is to be permitted to accrue in the boiler, and the
consequent greatest height of column of mercury to be accommodated without
escape under normal working conditions. f is a vessel into which the mercury g
will be discharged if forced out of the pipe e as set forth. is an aperture in the
chamber a normally closed by a screw plug h¹. On the plug being taken out any
scale or fur that may have accumulated within the chamber a or connection c can
be easily removed, after which the plug can be replaced.
Having now particularly described and ascertained the nature of the said inven-
tion and in what manner the same is to be performed I declare that what I
claim is :―
1. Providing boilers such as hereinabove referred to with a safety valve_com-
prising a mercury-containing chamber in communication with the interior of such
boiler and with a stand pipe the arrangement being such that should excessive
pressure arise in the boiler the mercury will be discharged so as to afford relief
by allowing fluid to escape from the boiler and that the mercury will be collected
for re-use.
2. My improved mercurial safety valve as described and illustrated for the
purpose specified.
Dated this 20th day of April 1894
WILLIAM PARKER.
W. Lloyd Wise,
46, Lincoln's Inn Fields, London, W.C.