IMPROVE- MENTS IN STEAM BOILERS
Year: 1881

page_text: LETTERS PATENT to Joseph Linington Rastrick, of Draper's Gardens,
Throgmorton Street, in the City of London, for an Invention of "IMPROVE-
MENTS IN STEAM BOILERS."
PROVISIONAL SPECIFICATION left by the said Joseph Linington Rastrick
at the Office of the Commissioners of Patents on the 3rd October 1881.
JOSEPH LININGTON RASTRICK, of Draper's Gardens, Throgmorton Street, in the
City of London. " IMPROVEMENTS IN STEAM BOILERS."
The Invention has for its object improvements in that class of boiler in which a
descending hollow leg or water chamber is attached to the bottom of a cylindrical
boiler, and projects downwards below the fire bars; and my Invention relates to a
peculiar construction of parts whereby the deposit of scale or other foreign matter
on the crown and sides of the furnaces is prevented, joints or rivetted parts within
the furnace or furnaces are avoided, with the exception of a single joint which is in
such a direction and position as not to be injuriously affected by expansion and
contraction, and a freer communication and consequently circulation of the water
is obtained between the body of the boiler and the descending water chambers.
For this purpose, instead of forming the body of the boiler and the descending
water chambers as distinct and separate structures, which when completed are
rivetted together and communicate with each other only by holes formed in a
plate fixed between the two parts, I, according to one arrangement, form the boiler
with a pair of descending water chambers formed in such manner that a single
plate without joint or seam is presented to the fire; and I form the upper part and
the sides of the body of the boiler cylindrical, but from about the centre of such
cylinder I divide the lower part of the boiler into two parts, the inner sides of
which are preferably formed to curves similar to those of the sides of the body,
thereby producing two symmetrical portions, the sides of each of which approach
each other at their lower parts and gradually merge into the descending water
chambers; the plates forming these two parts or divisions of the boiler body meet
along the centre line of the boiler above the fire and are rivetted together.
The joints of the descending water chambers are placed below the fire bars, and
are consequently not injuriously affected by expansion and contraction. The fire
bars are placed just below the boiler body, and on a level or thereabouts with the
upper portions of the descending water chambers, and they are placed between and
on the outside of such descending chambers.
Suitable stays are fixed in the interior of the boiler as may be required.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent filed by
the said Joseph Linington Rastrick in the Great Seal Patent Office on the
3rd April 1882.
JOSEPH LININGTON RASTRICK, of Draper's Gardens, Throgmorton Street, in the
City of London. IMPROVEMENTS IN STEAM BOILERS."
16
The Invention has for its object improvements in that class of boiler in which a
descending hollow leg or water chamber is attached to the bottom of a cylindrical
boiler, and projects downwards below the fire bars; and my Invention relates to a
peculiar construction of parts whereby the deposit of scale or other foreign matter
on the crown and sides of the furnaces is prevented, joints or rivetted parts within
the furnace or furnaces are avoided, with the exception of a single joint which is
in such a direction and position as not to be injuriously affected by expansion and
contraction, and a freer communication and consequently circulation of the water
is obtained between the body of the boiler and the descending water chambers.
For this purpose, instead of forming the body of the boiler and the descending 1
water chambers as distinct and separate structures, which when completed are
rivetted together and communicate with each other only by holes formed in a plate
fixed between the two parts, I-form-the-boiler-with_a_pair of descending water
chambers formed-in-such-manner that a single plate without joint or scam is
presented to the fire, and I form the upper part and the sides of-the-body-of-the-
boiler cylindrical, but from about the centre of such cylinder I divide the lower
part of the boiler into two parts, the inner sides of which are preferably formed to
curves similar to those of the sides of the body, thereby producing two symmetrical
portions, the sides of each of which approach each other at their lower parts, and
gradually merge into the descending water chambers; the plates forming these
two parts or divisions of the boiler body meet along the centre line of the boiler
above the fire and are rivetted together.
The joints of the descending water chambers are placed below the fire bars, and
are consequently not injuriously affected by expansion and contraction. The fire
bars are placed just below the boiler body and on a level or thereabouts with the
upper portions of the descending water chambers, and they are placed between and
on the outside of such descending chambers. Suitable stays are fixed in the
interior of the boiler as may be required.
And in order that my said Invention may be more clearly understood and
readily carried into effect, I will proceed, aided by the accompanying Drawings,
more fully to describe the same.
i

page_text: a plate fixed between the two parts, I form each boiler with a pair of descending
water chambers b, b, formed in such manner that a single plate without joint or
seam is presented to the fire, and I form the upper part and the sides of the body a
of the boiler cylindrical, but from about the centre a' of such cylinder I divide the
lower part of the boiler into two parts, the inner sides of which are preferably
formed as shewn to curves similar to those of the sides of the body a, thereby
producing two symmetrical portions, the sides of each of which approach each
other at their lower parts, and gradually merge into the descending water
chambers b, b; the plates forming these two parts or divisions of the boiler body a
meet along the centre line a¹ of the boiler above the fire, and are rivetted together
and to a plate a which is fixed, as shewn, to the crown of the boiler.
The joints of the descending water chambers b, b, are placed below the fire bars,
and are consequently not injuriously affected by expansion and contraction. The
fire bars c, c, are placed below the boiler body a, and on a level or thereabouts
with the upper portions of the descending water chambers b, b; suitable stays f,f,
are fixed in the interior of the boiler as may be required.
In the modification shewn at Figure 3 the upper half of the body of the boiler
is shewn connected by longitudinal joints a³ with the lower half thereof, and at
Figures 4 and 5 the several boilers are shown connected to two steam chambers or
superheaters.
Having thus described the nature of my said Invention, and the manner in
which I carry the same into effect, I would have it understood that what I claim
is the improvements in steam boilers, substantially as heroin described.
In witness whereof, I, the said Joseph Linington Rastrick, have hereunto
eet my hand and seal, this Eighth day of March, in the year of our Lord
One thousand eight hundred and eighty two.