IMPROVEMENTS IN FIXING SALT PANS AND IN ARRANGING THE FURNACES UNDER THE SAME
Year: 1872

page_text: PROVISIONAL SPECIFICATION left by Joseph Parks at the Office
of the Commissioners of Patents, with his Petition, on the 4th May
1872.
I, JOSEPH PARKS, of Wincham Boiler Works, Northwich, in the
County of Cheshire, do hereby declare the nature of the said Inven-
tion for "IMPROVEMENTS IN FIXING SALT PANS AND IN ARRANGING THE FURNACES
UNDER THE SAME," to be as follows:-
"
The object of the Invention is, first, to economise fuel and consume
smoke; secondly, to arrange the furnace under the pan in such a
manner that free access to any part of the pan for the purpose of repairs
can be had without the loss and risk attending the present mode of
working. The system usually adopted is to build a number of flues
leading from the several furnaces (generally consisting of three or
four under each pan), and place the pan on the walls of the flues. The
common size of pan is about 70 feet × 24 feet × 2 feet deep anḍ
weighs about 16 tons. They are provided with a number of rings
round the sides for the purpose of lifting the pan during the repairs,.
and it frequently happens that great damage is done to the flues and
pan in the process of lifting and lowering them.
.

page_text: The present form of flue also occupies a considerable space of heating
surface, and in case of any leakage occurring the brine which leaks
out percolates into the brickwork, forms masses of salt, and rifts the
walls to pieces.
In course of time the flues and spaces under furnaces get choked up
with salt accumulating in this manner, and it frequently happens that
the pans are actually lifted off their seatings by the salt forming large
masses, technically called "cats," which are caused by the leakage as
before described.
Now the present improvement consists in dispensing with flues :
altogether, with the exception of such flues as may be necessary for
conducting the smoke to the chimney after it has left the pan. This is
done by placing the pan on the four outside walls, and supporting the
central parts of the pan on columns about 6 feet high. By so doing
any portion of the pan can be readily inspected and repaired without
lifting, and the whole surface of the bottom is exposed to the heat
without the loss of the space now occupied by the flue walls and furnace
"solids." The front portion of the pan is supported on columns which
at about 2 feet from the ground carry the furnace bars and fittings on
brackets cast on the columns. The back end of the furnace bars rest
on the cross wall which is only carried up to the level of the fire-bars.
Between each pair of columns a furnace is fixed so that five columns
suffice for four furnaces. The furnaces may be separated from each other
for the length of the bars, if desired, and an air hole or flue for admission
of air to the back part of the fire may be used so as to assist the com-
bustion of the fuel, or in lieu of these walls one or more hollow pipes
may be fixed, so as to rest on the side bearers of the furnace, and they
not only support the pan but by perforating them with small holes and
allowing the air to enter the pipe from beneath the furnace a constant
supply of air for assisting the combustion may be obtained in lieu of
the flues above mentioned which are usually adopted.
The advantages therefore consist in forming the whole space under the
pan into one large chamber, which has the effect of not only using all
the surface of the pan as heating surface but allows of better and more
free combustion of fuel than can be effected in flucs. Any portion of
the pan can be repaired at little cost and the injurious effects arising
from leakage as before described are totally avoided. The columns are
connected together by T iron bearers. These bars are for the purpose

page_text: of assisting in supporting the pan when the thinness of the plates require
it. A jacket may be used round an iron chimney to warm brine before
entering the pan, and in case a brick chimney is used tubes or a small
flue tank may be applied for the same purpose.
°
This principle of fixing pans has the advantage of doing away
altogether with the lifting of the pans during repairs, and also gives
facility for using cast-iron pan rims which are much cheaper than
wrought-iron ones, and as the salt has a much less effect on them they
will wear a longer time.