IMPROVEMENTS IN STEAM BOILERS
Year: 1883

page_text: (Void by reason of the Patentee having neglected to file a Specification in
pursuance of the conditions of the Letters Patent.)
PROVISIONAL SPECIFICATION left by the said Henry Johnson at the Office
of the Commissioners of Patents on the 30th May 1883.
HENRY JOHNSON of Burgess Hill in the County of Sussex, Architect
"IMPROVEMENTS IN STEAM BOILERS."
The object of the present improvements in steam boilers is to accelerate the
generation of the steam and facilitate its maintenance at working pressure
whereby a considerable economy in fuel is effected.
To this end the invention consists in the use of dividing plates or water casings
which are so arranged with respect to the flue tubes that the products of com-
bustion will be directed backwards and forwards or in a circuitous direction
through the several sets or groups into which the flue tubes are divided, and the
heat of the products of combustion will be fully utilized before they escape to the
smoke stack.
According to my invention the several sets of flues are arranged to open at
either end into chambers within which are situate the dividing plates or water
casings above referred to, which act as baffles for directing and returning the
products of combustion, and by this arrangement the said water casings or baffles
may be easily fitted in place or repaired.
In applying my invention to the boiler of an ordinary locomotive, for example,
I place a transverse vertical water baffle at the back of the furnace causing the
gases of combustion to divide and pass around the baffle into two sets of flue tubes,
one set on each side of the boiler, and I arrange two of such water baffles within
the smoke box, dividing it thereby into 3 separate compartments, the products
of combustion issuing from the two sets of flue tubes above named being deflected
Prine 71

page_text: and returned to the chamber formed by or situate immediately behind the baffle
plate near the furnace. In this chamber the two streams of heated gases unite
and return to the central compartment of the smoke box and thence to the smoke
stack.
The spaces at each side of the fire box are occupied preferably by vertical water
pipes by or around which the heated gases are carried before passing through the
several sets of flue tubes.
These water pipes are screwed through the top and bottom plates of the fire-box
or combustion chamber, and the water casings or baffles forming the divisions of
the several chambers are suitably stayed and secured to the adjacent parts of the
boiler. The flue tubes are screwed through the end plates of the boiler, or the
flues may be otherwise formed and fixed.
The door of the smoke box is utilized to form a part of the chambers at that end
of the boiler, being constructed to shut against and on the projecting division
plates and water casings.
The water casing next the furnace precludes any heat from passing to the smoke
box direct from the furnace.
The boiler may be made in any form and the several flues may be so connected
as to return the heat in opposite directions successively within the boiler or
consecutively from side to side, or from top to bottom, or from end to end thereof.
In order to allow of the greatest possible number of flue pipes to be screwed
through the end plates of the boiler without interference from the water casings
forming the divisions or baffles, these latter may have plates of iron attached and
projecting to form a suitable connection with the end plates of the boiler, but
otherwise the water casings will abut closely against the end plates of the boiler.
The water casings are fitted with suitable pipes and junctions at bottom to
admit water to the interior of the casing as it is pumped into the boiler, and with
pipes or outlets at the top to allow the steam to escape, the water in the casing
always remaining at the same level as the water in the boiler. By disconnecting
these pipes and junctions the water casings can be readily removed to allow the
flues to be examined.
This system can be readily adapted to the boilers of existing locomotive, traction,
portable or fixed or other engines for the purpose of economizing fuel and
repeating the heat of the gases from the furnace before they escape to the shaft.
*The diameters of the tubes in the several sets will be suitably proportioned to
produce efficient results, the total tube area being made about the same in all
the sets