IMPROVEMENTS IN APPARATUS CONNECTED WITH STEAM BOILERS
Year: 1867

page_text: LETTERS PATENT to Robert David Napier, of 20, Church Row, Limehouse,
in the County of Middlesex, for the Invention of "IMPROVEMENTS IN
APPARATUS CONNECTED WITH STEAM BOILERS."
Sealed the 30th August 1867, and dated the 9th March 1867.
PROVISIONAL SPECIFICATION left by the said Robert David Napier at
the Office of the Commissioners of Patents, with his Petition, on the
9th March 1867.
I, ROBERT DAVID NAPIER, of 20, Church Row, Limehouse, in the County
of Middlesex, do hereby declare the nature of the said Invention for "Iм-
PROVEMENTS IN APPARATUS CONNECTED WITH STEAM BOILERS," to be as follows:-
This Invention has for its object improvements in apparatus connected with
steam boilers. In order to prevent steam boilers priming, that is to say,
to prevent the steam passing away from the boiler carrying water with it, I
cause the steam after leaving the boiler to pass through a vessel which I call
a separator. The passage which admits the steam is so directed that if water
enters the separator along with the steam it is by its impetus carried away
from the passage by which the steam is led away from the separator. The
water entering the separator in this manner returns to the boiler by a passage
provided for the purpose.

page_text: In the arrangement I prefer a casing is mounted on the top of the boiler,
the steam is led in on one side and conducted away by another passage on the
same side of the casing and above the passage by which it enters. From
the bottom of the casing a pipe of large diameter passes into the boiler to
lead back the priming water. When steam is blown into water or other
liquid with a view either to get rid of waste steam or of heating the liquid it
is frequently desirable to avoid noise, for this purpose I cause the steam to
pass from a smaller to a larger pipe and at the same time to draw into this
larger pipe sufficient liquid for its condensation; in this way steam may be
passed into water or liquid without noise.
SPECIFICATION in pursuance of the conditions of the Letters Patent, filed
by the said Robert David Napier in the Great Seal Patent Office on
the 9th September 1867.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, ROBERT DAVID
NAPIER, of 20, Church Row, Limehouse, in the County of Middlesex, send
greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her Letters
Patent, bearing date the Ninth day of March, in the year of our Lord One
thousand eight hundred and sixty-seven, in the thirtieth year of Her reign, did,
for Herself, Her beirs and successors, give and grant unto me, the said Robert
David Napier, Her special licence that, I, the said Robert David Napier,
my executors, administrators, and assigns, or such others as I, the said Robert
David Napier, my executors, administrators, and assigns, should at any time
agree with, and no others, from time to time and at all times thereafter during
the term therein expressed, should and lawfully might make, use, exercise,
and vend, within the United Kingdom of Great Britain and Ireland, the
Channel Islands, and Isle of Man, an Invention for "IMPROVEMENTS IN
APPARATUS CONNECTED WITH STEAM BOILERS," upon the condition (amongst
others) that I, the said Robert David Napier, my executors, or administrators,
by an instrument in writing under my, or their, or one of their hands and seals,
should particularly describe and ascertain the nature of the said Invention,
and in what manner the same was to be performed, and cause the same to be
filed in the Great Seal Patent Office within six calendar months next and
immediately after the date of the said Letters Patent.
NOW KNOW YE, that I, the said Robert David Napier, do hereby
declare the nature of the said Invention, and in what manner the same is

page_text: to be performed, to be particularly described and ascertained in and by the
following statement thereof, that is to say :-
The first part of my Invention has for its object to separate priming water
from steam on its passage from a boiler to an engine or other place, and to
cause the water so separated to return to the boiler. For the above purpose
the steam is made to pass through a vessel, which I call a separator, which is
connected to the boiler by two pipes or passages of which one is the inlet pipe
for the steam and communicates between the steam space in the boiler and
the top of the separator, or as high in it as may be convenient, while the other
which is the return pipe for the water leads from the bottom of the separator,
or as low as may be convenient in it, to any convenient position below the
level of the water in the boiler. The outlet pipe by which the steam leaves
the separator is so situated with regard to the inlet pipe that the steam in
passing from the one to the other must suddenly change its direction of
motion, while the water which may have been in combination with the steam
is carried forward by reason of its greater relative density and momentum till
falling to the bottom or coming in contact with and running down the sides
of the separator it is conveyed back to the boiler by the return pipe. This
part of my Invention will be better understood by reference to the accompany-
ing Drawing, Figure 1, which represents a sectional elevation of a portion
of a boiler fitted with a separator according to my Invention.
A is the separator; B, the inlet pipe by which the steam enters the
separator; C, the return pipe by which the water is conveyed back to the
boiler; and D is the outlet pipe by which the steam leaves the separator. I
prefer to make the inlet pipe considerably larger than the outlet. The return
pipe I prefer to make somewhat larger or at least as large as the inlet pipe,
for I have found experimentally that when these dimensions are not main-
tained the separator is liable to fill with water from time to time, and it then
ceases to separate the water which comes over with the steam. If the return
pipe is made very much smaller than the inlet pipe the vessel A will not
practically act as a separator. It is generally desirable to have a gauge glass
on the separator by which the attendant may be at all times informed of the
beight of the water in it, and I sometimes put a stop valve on the return pipe
for the purpose of ascertaining the rate at which the water is passing through
the separator, which can be done by shutting the stop valve for a short time
and observing the rate at which the separator then fills with water.
One great advantage of the arrangement described for dynamically drying
steam is that the steam space in a boiler does not require to be nearly so
large as when an ordinary steam chest is used, and another advantage is that

page_text: when properly constructed the passage of water with steam from a boiler to
an engine becomes nearly if not quite an impossibility.
In the second part of my Invention, which has for its object the getting
rid of waste steam without the noise usually attendant on blowing steam
either into water or air, I make use of the momentum of steam in passing
from a pipe or passage into a larger pipe to produce a partial vacuum in the
larger pipe, and by this means to create a current of water into it of sufficient
volume to condense the steam. The large pipe above mentioned is the escape
pipe, and is open at the end for the free escape of the condensed steam and
water which the steam has drawn in. I prefer that the outer end of the
escape pipe should be near the water line or under it, and I also prefer for the
purpose in view when fitting ships or vessels to use a pipe which is independent
of the usual waste steam pipe in connection with the safety valve.
The accompanying Drawing, Figure 2, represents in section a waste steam
pipe according to this part of my Invention and connected to the side of a
vessel.
A is the waste steam pipe; B, the enlarged pipe, and C a pipe of which
the end F must be below the surface of the water; D represents the water
level outside, but the pipe B may be either under the water level or con-
siderably above it. The steam on passing through the nozzle E into the
enlarged pipe B produces a partial vacuum in it which causes the water to
rush through the pipe C into B where it condenses the steam and is im-
pelled outwards by the impetus imparted to it by the condensed steam. By
this arrangement any quantity of steam can be blown off with hardly any
perceptible noise. The getting rid of waste steam quietly is frequently of
great moment, as for instance in cases of collision or when a steamer has to
be suddenly stopped to avoid one, or in foggy weather when it is important
that the signals of other vessels should be beard.
The same arangement is also applicable when steam is blown into water or
liquid for the purpose of heating it.
In witness whereof, I, the said Robert David Napier, have hereunto
set my hand and seal, this Thirty-first day of August, in the year of
our Lord One thousand eight hundred and sixty-seven.
ROB. D. NAPIER. (LS.)