IMPROVEMENTS IN THE CONSTRUCTION OF LOCOMOTIVE AND OTHER STEAM BOILERS, AND IN PARTS CONNECTED THERE- WITH.
Year: 1877

page_text: LETTERS PATENT to Francis Bristow, of Wandsworth, in the County of Surrey,
Boiler Maker, for the Invention of "IMPROVEMENTS IN THE CONSTRUCTION OF
LOCOMOTIVE AND OTHER STEAM BOILERS, AND IN PARTS CONNECTED THERE-
WITH.
Sealed the 16th November 1877, and dated the 2nd August 1877.
PROVISIONAL SPECIFICATION left by the said Francis Bristow at the
Office of the Commissioners of Patents on the 2nd August 1877.
.
FRANCIS BRISTOW, of Wandsworth, in the County of Surrey, Boiler Maker.
"IMPROVEMENTS IN THE CONSTRUCTION OF LOCOMOTIVE AND OTHER STEAM
BOILERS, AND IN PARTS CONNECTED THEREWITH."
The object of this Invention is to economize fuel and prevent smoke in locomotive
and other similar tubular boilers. For this purpose I, firstly, stay the fire-box or
other surfaces which require and are exposed to the heat of flame or gases by
means of stays of a peculiar construction. The outside end of the stay is
secured or screwed into the outer fire-box plate; the part of the stay in the water
space is by preference not screwed, in order that dirt may not so easily settle on it;
the other part, or end of the stay, consists of an enlarged cylindrical part screwed
through the inner copper fire-box and resting with a flange or shoulder on the inside
thereof;
this enlarged part is formed with a recess from the inside and enters into
the water space. I thereby gain an increase of surface, namely, the interior of the
recess exposed to and taking up the heat; and an increased surface, namely, a
portion of the exterior of the aforesaid enlarged part of the stay exposed to the water,
giving out the heat thereto; the surfaces are at the same time effectually stayed,
and the flange on the inside of the stay prevents the coal and coke from scraping
against the copper fire-box. The stays may conveniently be roughed out by the
steam hammer and finished in the lathe. When inserted, the outer end is rivetted
over.

page_text: For ordinary locomotive fire-boxes I may place these stays, say, about seven
inches from centre to centre, and make the enlarged part about four inches diameter.
To the copper tube plate in the fire-box, just below the lowest row of tubes, I fit
a deflecting shield or guard, or fender plate, which may conveniently be in two
halves and suspended by hooks so as to be easily removed when required; it rises
in a curve, receding back from the tube plate, and causes the flame and gases to
take a longer route before entering the lowest, say, the three lowest rows of tubes;
I further box in the upper corner between the same tube plate and the crown of the
inner fire-box, so that the upper tubes, say, three rows of same, are enclosed thereby.
I fit a door to this box for inspecting the tube. In the smoke box I similarly box
in all the tubes, except one or more top rows, say, the two uppermost rows, and I
also fit this box with a door. The consequence of this arrangement is that the heat
and flame in the fire-box first passes over the deflecting shield, then through the
lower rows of tubes to the smoke box, then back to the front by the middle rows of
tubes, and then from front to back or chimney end through the top rows of
tubes.
I prefer to make the chimney short and slightly smaller at the top than at the
root, and of cast brass or other suitable metal.
To the top of the fire-box I fit a "dust cock" of a peculiar construction, viz.,
with two ways through the plug and with corresponding branches to the boxed-in
parts in the fire-box and the smoke box; when it is desired to blow out the slight
amount of ashes accumulated in the said boxed-in parts, first set the cock so as to
blow the ashes from the back box to the front box, thence turn the cock the other
way against a suitable stop, and the steam will then be let into the front box and
blow the contents of same through the uppermost rows of tubes and thence out
through the chimney.

page_text: "
SPECIFICATION in pursuance of the conditions of the Letters Patent filed by
the said Francis Bristow in the Great Seal Patent Office on the 2nd February
1878.
_FRANCIS BRISTOW, of Wandsworth, in the County of Surrey, Boiler Maker.
'IMPROVEMENTS IN THE CONSTRUCTION OF LOCOMOTIVE AND OTHER STEAM
BOILERS, AND IN PARTS CONNECTED THEREWITH.'
"
The object of this Invention is to economize fuel and prevent smoke in locomotive
and other similar tubular boilers. For this purpose I, firstly, stay the fire-box or
other surfaces which require staying and are exposed to the heat of flame or gases
by means of stays of a peculiar construction.
On the accompanying Drawing, Figure 1, which is a longitudinal section through
a locomotive boiler constructed according to my Invennion, I have shewn such stays
as applied to the fire-box flat surfaces; A, A, are the stays. Figure 2 is an enlarged
view. The outside end of the stay is secured or screwed into the outer fire-box
plate B; the part of the stay in the water space is, by preference, and as here shown
clearly in Figure 2, not screwed in order that dirt may not so easily settle on it; the
other part or end of the stay consists of an enlarged cylindrical part screwed through
the inner copper fire-box C, C', and resting with a flange or shoulder on the inside
thereof; this enlarged part is formed with a recess from the inside and enters into
the water space. I thereby gain an increase of surface, namely, the interior of the
recess exposed to and taking up the heat of the fire; and an increased surface,
namely, a portion of the exterior of the aforesaid enlarged part of the stay exposed
to the water giving out the heat thereto; the surfaces B and C are at the same time
effectually stayed and held together, and the flange on the inside of the stay
prevents the coal and coke from scraping against the copper fire-box. These stays
may conveniently be roughed out by the steam hammer and finished in the lathe.
When inserted the outer end is rivetted over, as shewn.
For ordinary locomotive fire-boxes I may place these stays, say, about seven
inches from centre to centre, and make the enlarged part about four inches outside
diameter.
To the copper tube plate C' in the fire-box, just below the lowest row of tubes, I
fit a deflecting shield or guard, or fender plate D, which may conveniently be in two
halves and suspended by hooks so as to be easily removed when required; it rises
in a curve, receding back from the tube plate C₁, and causes the flame and gases to
take a longer route before entering the lowest, say, the three lowest rows E, E, E, of
tubes.
It may be protected against the fierce heat by means of fireproof material,
as shewn in dotted lines; or the deflecting shield D may be in the form of an arched
water bridge communicating with the water spaces at each side of the fire-box; this
water bridge may communicate with the water space by means of hollow trunnions
at the lower part of the bridge, which can thus be swung up or down and adjusted
any angle.
to
I further, by means of the box F, close or box in the upper corner between the
same tube plate C¹ and the crown C" of the inner fire-box, so that the upper tubes,
say, three rows of same, G, G, G, are enclosed thereby. I fit a door to this box for
inspecting the tubes. This door may be hinged on, but I prefer to make it in two
parts g and g sliding past each other and guided at top and bottom, as shewn. In
the smoke box I similarly, by means of a casing H, box in all the tubes except onc
or more top rows, say, the two uppermost rows, and I also fit this box with a door
which may be hinged on, but by preference made in two parts, h and h¹, sliding
past each other, and also guided at top and bottom, as shown. The consequence of
this arrangement is that the heat and flame in the fire-box first pass over the
deflecting shield D, then through the lower rows (E, E, E,) of tubes to the smoke
box, then back to the front by the middle rows of tubes, and then from front to
back or chimney end through the top rows of tubes.

page_text: I prefer to make the chimney short and slightly smaller at the top than at the
root, as shewn in Figure 1, and of cast brass or other suitable metal.
To the top of the fire-box I fit a "dust cock" of a peculiar construction. A cock of
this description is shewn in section at Figure 3; it is made with two ways, a and b,
through the plug and with corresponding branches, A and B, to the boxed-in parts in
the fire-box and the smoke box at Fand H, Figure 1, respectively; when it is desired
to blow out the slight amount of ashes accumulated in the said boxed-in parts, first
set the cock so as to blow the ashes from the back box H to the front box F, then
turn the cock the other way against a suitable stop, and the steam will then be let
into the front box F and blow the contents of same through the uppermost rows of
tubes and thence out through the chimney.
And having thus described and ascertained the nature of this my Invention, I
declare that I claim,-
Firstly. The construction of stays substantially as and for the purposes set
forth.
Secondly. The guard plate D in combination with the boxes F and H applied to
tubular boilers, substantially as and for the purposes set forth.
Thirdly. The dust cock applied and operating substantially as set forth.
In witness whereof, I, the said Francis Bristow, have hereunto set my hand
and seal, this Seventeenth day of January, in the year of our Lord One thousand 2
eight hundred and seventy-eight.
TD NAIS
DRISTON