IMPROVEMENTS IN STEAM GENERATORS, AND IN FURNACES THEREFOR
Year: 1870

page_text: PROVISIONAL SPECIFICATION left by William Robert Lake at the
Office of the Commissioners of Patents, with his Petition, on the
30th June 1870.-A communication from abroad by S. Lloyd
Wiegand, of Philadelphia, Pennsylvania, United States of America.
I, WILLIAM ROBERT LAKE, of the Firm of Haseltine, Lake, & Co.,
Southampton Buildings, London, Patent Agents, do hereby declare the
nature of the said Invention for "IMPROVEMENTS IN STEAM GENERATORS,
AND IN FURNACES THEREFOR," a communication, to be as follows:-
This Invention consists partly in forming boilers with their heating
surfaces composed of tubes suspended in the furnace from an upper
vessel or vessels in compartments so small as to render them safe from
any possibility of explosion, and making the compartments to com-
municate with each other in such a manner that a circulation is
maintained through the several compartments while the cleanliness
of the heating surfaces and the rapid and economical generation of
steam are increased.
In additions to the improvements above stated this Invention embraces
an improved form of cap or cup for the lower terminations of the

page_text: 1
suspended tubes which afford larger space for the passage of the cir-
culating currents, also an improved connection for uniting the several.
vessels possessing great facility of application and renewel of joints,
and great flexibility and durability when in use.
Included in this Invention is a mode of forming tanks of small cross
sectional area in folds or coils so as to cheaply make small portable
boilers with few joints, and a new mode of making a furnace in sections,
or staves specially applicable to locomotive, marine, and river service
in conjunction with the steam generator herein described.
The upper vessels or tanks of which this generator is composed are
made in two or more compartments which are horizontal, or nearly so,
and of small cross sectional area and are directly over each other. The
water is introduced in the second compartment, the tubes forming the
heating surfaces are inserted into the bottom of the lowest compartment.
The lower ends of the tubes are closed by screw caps of an inverted
conical shape below the screwed portion, and with channels opening
upward through the oblique sides of the cone from the apex or central
portion of the cone, the boshes formed by the oblique sides of the cone
between the channels serve to support in central position a guide for
conducting a current of fluid from the second compartment through a
suitable aperture in the bottom thereof downward to the bottom of the
cap, whence the current rises through the channels in the caps already
described, and passing up the annular space between the tube and guide
into the lowest compartment of the tank. The guide for conveying the
currents downward through the centres of the tubes may be either a
simple cylindrical tube open at both ends, or may be made in the form
of a spiral coil having a clear central space or channel extending within
the coils from the top to the bottom, and having coils made inclined
upward from the centre outward. This form of coil deflects the
descending current towards the centre, and the ascending current out-
ward toward the tube in which the coil is placed, thus avoiding any
interference between the descending and ascending currents. It also
permits, when the water level in the steam generator has fallen into the
tubes, a flow of water to return from the ascending column in the tube
through the interstices between the coils of the spiral guide to the
descending column in the centre of the guide, thus maintaining a
circulation in the tubes after the water level has fallen below the tank
or upper vessel. An aperture or apertures in the partition plate forming

page_text: the bottom of the second compartment, and the top of the lower com-
partment made at a point or points remote from the place of introduction
of the feed water permits the current of mingled steam and water which
rises from the annular spaces in the tubes when heat is applied to
them to pass from the lower to the second compartment of the tank
where the steam separates from the water; or there may be other
chambers connected by suitable necks placed above the second chamber,
into which the mingled steam and water rise, and the steam is with-
drawn from the highest part of the tank or vessel at a point or points
remote from the aperture communicating from the lower compartment
of the tank to the compartment above it. A flow of water horizontally
is produced towards the steam outlet in the upper compartment, and in
the course of this flow the steam and water separate. The separation
of the steam and water is facilitated by placing oblique obstructions or
bars, which are so inclined as to deflect the water and allow the steam
to pass over the top of them.
When a small boiler or steam generator is to be made it is formed
with one tank in the shape of a spiral coil in a horizontal plane with a
flue between the several coils thereof, or it may be made in folds in
a labyrinthian annular or other form so as to make the tank of sufficient
length to afford a proper distance for the horizontal flow of the water
in the compartments or chambers of the tank, and at the same time to
be conveniently applicable to a furnace.
When a large generator is to be made it is best done by uniting a
number of tanks formed in compartments, as herein-before described,
to a common feed pipe, and a common steam drum with flues between
the several tanks.
The device employed for connecting the tanks to the feed pipe and to
the steam drum is another feature in this Invention; a tubular return
bend is made with bearing faces formed in the shape of spherical concave
zones surrounding the inlet and outlet thereof, and applied to short tubes
or collars having correspondingly formed surfaces, which short tubes or
collars are in turn applied to suitable spherical seats surrounding the
apertures in the tanks in the feed pipes and in the steam drum; this
return bend is clamped centrally by any known means against the short
tubes, thus holding them to their seats on the tanks and steam drum
and feed pipe, and forming a conveniently applied and cheap fluid

page_text: connection of sufficient flexibility to avoid strain from expansion and
contraction of the various parts of the generator.
When used for purposes of navigation I set these boilers in furnaces
formed of vertical staves tongued and grooved together and made
hollow to contain water; these staves are put in fluid communication
with a feed or supply pipe and the tanks of the steam generator by
means of the connecting pieces or return bends, and short spherical
faced tubes, such as herein-before described, applied at the upper and
lower ends of the staves. A vertical partition extending nearly to the
top and bottom in the cavity of each of the staves serves to divide and
separate the ascending and descending currents produced by heating
the water therein. By making these staves of small cross sectional area
risk of disastrous explosion is avoided, and by grooving and tongueing
them together sufficient play is afforded to avoid any straining from
expansion and contraction without a possibility of flame passing the
interstices between the staves.