Improvements in the Construction of Fire Boxes of Steam Boilers.
Year: 1885

page_text: Improvements in the Construction of Fire Boxes of Steam
Boilers.
I, SAMSON Fox, of the Leeds Forge, New Wortley, Leeds, in the County of
York, Engineer and Ironmaster, do hereby declare the nature of my said invention
for "IMPROVEMENTS IN THE CONSTRUCTION OF FIRE-BOXES OF STEAM BOILERS,"
to be as follows:-
.
Fire boxes of steam boilers of the locomotive type are usually built up of parts
rivetted together, a mode of construction that involves considerable labour, besides
which the rivetted joints are liable to leakage.
Now according to my invention I dispense with rivetted joints in such fire
boxes, which to this end are made in one piece as I proceed to describe.
A plate of any suitable metal such as mild steel, of appropriate shape and
thickness, is heated to a suitable degree, then pressed by and between a series
of male and female dies operated by hydraulic power or otherwise, such dies being
of forms that will by successive pressing operations impart to the metal the
shape of the required fire box. The metallic plate is reheated previous to each
successive pressing operation.
When a plain fire box is required with sides and crown thinner than the shell
of the boiler in which it is to be used, in order that the part in which the tubes
are to be inserted may give a better bearing than a thin plate would afford, such
part is made thicker than the other parts, the extra thickness being at the inner
or fire side of the box, and those parts of the sides intended to receive stays are
formed with ribs so as to provide therein the same number of screw threads or a
hold equal to that afforded in the boiler shell, thus preventing liability to stripping
of the stays at one end before the other.
A corrugated fire box can be produced by the use of male and female dies
appropriately formed, the part for the reception of the tubes is left plain and is
made of extra thickness as previously described with respect to a plain fire box,
and provision is made for the reception of the stays on the outside ridges forming
the corrugations which parts are made of equal thickness with the shell of the
boiler to which the fire box is to be applied for the purpose above referred to.
Dated this ŏġ1st dow of T....' AD 100%

page_text: Improvements in the Construction of Fire-boxes of Steam
Boilers.
I, Samson Fox, of the Leeds Forge, New Wortley, Leeds, in the County of
York, Engineer and Ironmaster, 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:-
Fire boxes of steam boilers of the locomotive type are usually built up of parts
rivetted together, a mode of construction that involves considerable labour, besides
which the rivetted joints are liable to leakage.
Now according to my invention I dispense with rivetted joints in such fire
boxes, which to this end are made in one piece as I proceed to describe.
A plate of any suitable metal, such as mild steel of appropriate shape and
thickness is heated to a suitable degree, then pressed by and between a series of
male and female dies operated by hydraulic power or otherwise, such dies being
of forms that will by successive pressing operations impart to the metal the shape
of the required fire-box. The metallic plate is reheated previous to each successive
pressing operation..
When a plain fire-box is required with sides and crown thinner than the shell
of the boiler in which it is to be used, in order that the part in which the tubes
are to be inserted, may give a better bearing than a thin plate would afford, such
part is made thicker than the other parts, the extra thickness being at the inner
or fire side of the box, and those parts of the sides intended to receive stays are
formed with ribs or projections so as to provide therein the same number of screw
threads or a hold equal to that afforded in the boiler shell, thus preventing liability
to stripping of the stays at one end before the other.-A corrugated fire box can
be produced by the use of male and female dies appropriately formed, the part for
the reception of the tubes is left plain and is made of extra thickness as previously
described with respect to a plain fire box, and provision is made for the reception
of the stays on the outside ridges forming the corrugations, which parts are made
of equal thickness with the shell of the boiler to which the fire box is to be
applied, for the purpose above referred to.
In the accompanying drawings, Figs. 1. and 2. represent approximately a form
of metallic plate a. for the manufacture of a fire box in one piece according to my
invention. This plate a, while in a heated state is placed upon a female die b
shewn in plan in Fig. 3. Sheet 1. and in sectional elevation in Fig. 4, and is guided
into position thereon by aid of the projecting parts 61. A male die c, Fig. 4,
(a cross section of which in the line 1. 1. is shewn in Fig. 3) is operated by
hydraulic or other suitable power and caused to press the plate a, into the female
die wherein it assumes a dished form as shewn in Fig. 4. The metallic plate
(which is marked with the letter a, in all subsequent Figures illustrating the
various operations) is reheated previous to each operation. Fig. 5, shews in
sectional elevation male and female dies d, e-Fig. 6, is a cross section of the

page_text: same on the line 2..2. of Fig. 5.-Fig. 7, is a plan of the female die e.-This pair
and the following pair of dies shown at f, g, in Fig. 8, (the latter in vertical
section) are for effecting the closing in of the open end of a, and stretching it by
degrees into a rectangular form and for gradually reducing the radius of the
corners. Fig. 9, is a plan of Fig. 8. one half being in section on the line-3. 3. of
Fig. 8. Fig. 10 shews in elevation a male die h, and in sectional elevation a
corresponding female die i, and Fig. 11. is a plan of the same, half in cross section
on the line 4, 4, of Fig. 10.-Fig. 12, shews in elevation another male die j, and in
sectional elevation the corresponding female die k, and Fig. 13, is a plan of the
same, one. half being in cross-section on the line 5, 5, of Fig. 12. These are for
further reducing the radius of the corners of a-Fig. 14, shews in elevation
another male die l, and in sectional elevation a corresponding female die m, and
Fig. 15, is a plan of the same with one half in cross section on the line 6-6, of
Fig. 14. This pair is for reducing the corners of the plate a, (now a partially
formed fire-box) to the radius required. The male die l, is built up in sections so
that the central part 1. may be withdrawn immediately the pressing operation
is performed thus enabling the remaining sections to collapse sufficiently or to be
easily removed to allow of the contraction of the now nearly completed fire box
due to cooling. The fire box being of one thickness throughout or approximately
so is next subjected to the pressing of such parts as require to be reduced in
thickness. Fig. 16, is a plan of a male die n, Fig. 17 shews the same in elevation
and a corresponding female die o, in sectional elevation, the latter being provided
with a bottom part p, to support the box whilst under treatment. Fig. 18, shews
in cross section the male die n, on the line 7. 7. in Fig. 17, built up in parts in a
similar manner to the die 2, shewn in Figs. 14 and 15, this die n, is provided with
projections n 1. and on being pressed into the fire box a, forms alternate recesses a 2,
and projections a 3, therein (as shewn in Figs. 20. 21. 22) such projections being
for the insertion of staybolts, while the part a 1, into which the tubes are to be
inserted remains of the normal thickness that obtained previous to this operation.
Fig. 19, is a plan of the female die o, which is shewn in two parts, but may be in
one if desired. Fig. 20. Sheet 2. shews in vertical section on the line 8. S. of
Fig. 22, a fire box as completed by the above described process. Fig. 21, is an
elevation at right angles to Fig. 20, one half being in section on the line 9. 9. of
Fig. 22, which latter is a plan of the underside, a 3, are the projections or ribs for
receiving the stay bolts, rendering the fire box at these parts about equal in
thickness to the outer shell of the boiler, thus affording equal hold therein for the
Baid stays. The plain part a 1, Figs. 20, and 21, which remains of the thickness
that obtained when the box left the dies l, m, Figs. 14, and 15, forms what is
known as the tube plate in fire boxes of ordinary construction. Fig. 23, is a
section of the fire box to an enlarged scale shewing the projecting ribs a 3, and
stay bolts therein. When a fire box of the corrugated type is required the last
described operation is omitted, and the partially formed fire box after being treated
by the dies l, m, is re-heated and subjected to the action of dies such as shewn in
the three following Figures. Fig. 24, shews male and female corrugating dies q, r,
the latter being in vertical section and provided with a bottom part s. for corru-
gating the crown of the box. The bottom of the male die q, has corresponding
configuration to that of s,-Fig. 25, is a sectional plan of the male die q, on the
line 10. 10. of Fig. 24, and Fig. 26, a sectional plan of the female die r, also on
the line 10. 10. Fig. 27, is a vertical section of a corrugated fire box on the
line 11,-11, Fig. 29, as produced by the above described process. Fig. 28, is an
elevation at right angles to Fig. 27. one half being in section on the line 12. 12,
of Fig. 29. (this latter being a plan of the underside) the plain and thick part a 4,
is to receive the tubes. Fig. 30, shews to an enlarged scale a section of the corru-
gated parts with staybolts inserted therein. The firing hole shewn in dotted
lines t, in both kinds of fire boxes Figs. 21, and 28, is formed afterwards, a portion
around such opening in the corrugated form being flattened for receiving the joint
ring usually placed between the fire box and the outer shell of the boiler.

page_text: Having now particularly described and ascertained the nature of my said
Invention and in-what manner the same is to be performed, I declare that what
Į claim is :—.
The manufacture of a fire box for a steam boiler of the locomotive type formed
without rivetted joints (with or without ribs or projections, and with or without
corrugations) of a plate of metal of suitable shape by heating and. pressing or
stamping substantially as hereinabove described.
Dated this 22nd day of April 1886.
L.
Witness,
THO E. CRAVEN, C.E.,
Fel. Inst. Patent Agents,
24, Victoria Chambers, Leeds.
SAMSO