IMPROVEMENTS IN STEAM BOILERS.
Year: 1884

page_text: We EDWARD HENRY NICHOLSON and ARTHUR THOMAS ALLCOCK of Newark
upon Trent. in the County of Nottingham. Engineers. do hereby declare the nature
of our Invention for IMPROVEMENTS IN STEAM BOILERS. and in what manner
the same is to be performed, to be particularly described and ascertained in and
by the following statement :-
Our Invention is for Improvements in Steam Boilers and relates especially to
those which have to be taken to pieces and packed in a small compass for
convenience of transport, and to reduce the weight and dimensions of such pieces.
That our Invention may be the better described and ascertained we have hereunto
appended 1 Sheet of drawings. Figure 1 is a vertical longitudinal section, Figure 2
a transverse section on the line x-x and Figure 3 a transverse section on the line y-y
of one section or division of a Boiler made in accordance with our Invention ;
Figure 4 is a longitudinal section and Figure 5 a partial end elevation and a partial
cross section of a complete Biler showing one method of grouping and seating two
such sections or divisions as are shown in Figures 1-2 and 3.
Each of these sections or divisions consists of two subsections A and A¹, the
lower one A being made in two parts a and a' which are bolted together with a
faced joint at b and furnished with the lower and upper tube plates c and c¹ through
which run the fire tubes d. The upper subsection A¹ is also made in two parts all
and all in a similar manner and bolted together at 61, the lower part all only is
provided with a tube plate c which carries the "Field Tubes "e: the upper part a¹ll
is furnished with a crown plate of ordinary construction. The two subsections A
and A' are connected together by a water tube B secured by lock nuts f to the
tube plates cl and c" and may be furnished with an inner circulating tube g reaching
nearly to the bottom of the subsection A. One method of arranging and seating
two such sections or divisions as above described is shown in Figures 4 and 5 where
the arrows mark the direction of the draught, the hot gases ascending through the
fire tubes d of the subsection A over the fire grate G and passing about the "Field
Tubes e of the upper subsection A', thence round the Field Tubes of the next
upper subsection and down through the fire tubes of its lower subsection to the
chimney H
"
The lower subsections are connected together by a water pipe W and the upper
subsections by a steam pipe S so that the water line of all the sections or divisions
may be at a level, and a free communication afforded between them.

page_text: t
In Figure 6, No. 1 shows a modification of a section or division, the subsections A
and A¹ being composed in three parts each; consisting, in the lower subsection A
of the shell a bolted by the flanged and faced joints b to the lower and upper tube
plates, c and cl, and in the upper subsection A¹ of the shell a bolted by the flanged
and faced joints b' to the lower tube plate c¹¹ and an ordinary crown plate.
The lower subsection A instead of having fire tubes passing through it is fitted
with "Field Tubes" e, and is connected with the upper subsection A' by three
water tubes B which are shown more clearly in the sectional plan Figure 7. The
water tubes B are connected to the tube plates c' and c" by flanged and faced
joints h secured with bolts. No. 2 in Figure 6 shows a section or division
constructed in a similar manner to No. 1 except that the water tubes B are
connected to their tube plates by lock nuts f in the same manner as described in
Figure 1.
In section or division No. 3 the water tubes B are secured in their tuhe plates
by expanding them in a slightly conical hole, the upper and lower subsections A¹
and A being further secured together by long stays & passing through the crown
and bottom tube plates and also through the water tubes B. The lower subsection A
of No. 8 is fitted with fire tubes & through which the hot gases rise after passing
amongst the lower Field Tubes e of sections or divisions No's 1 and 2, as shown
by the arrows, thence into the upper flue amongst the Field Tubes of sections or
divisions No's 3-2 and 1 and on to the chimney H.
The lower subsections are connected together by the water pipes W, shown
more clearly in the sectional plan Figure 7, and the upper subsections are connected
together by the steam pipes S. In building up the subsections A and A¹ we would
have it clearly understood that we do not contine ourselves to the exact number of
parts a and a¹ and of joints band b¹ as shown in Figures 1 and 0 as these may be
varied according to the size of the boiler required and the limit of weight and size
allowed for transport. In some cases also it may be advisable to use more than
two subsections to make up each section or division, three or more subsections can
be employed connected together by water tubes and fitted with either fire or Field
Tubes according to the direction of the draught.
Any number of sections or divisions so constructed may be employed according
to the power of the Boiler required, the lower subsections being connected together
at the bottom by water pipes W and the upper ones at the top by the steam
pipes S.
Having now particularly described and ascertained the nature of our said
Invention and in what manner the same is to be performed we declare that what
we claim is:—
The construction of Steam Boilers consisting of one or more sections or divisions,
each of such sections or divisions consisting of two or more subsections connected
together by one or more water tubes, and formed in parts or segments bolted
together; in combination with either Fire tubes or Field tubes or with both,
substantially as above shown and described, or any mere modification thereof.
Dated this 14th day of February 1884.