Improvements in and relating to Cornish Boilers.
Year: 1892

page_text: Date of Application, 21st June, 1892-Accepted, 23rd July, 1892
COMPLETE SPECIFICATION.
Improvements in and relating to Cornish Boilers.
I RUDOLF MÜLLER, of Reiherstieg Hamburg in the Empire of Germany,
Engineer 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 :-
.
This invention relates to boilers usually known as Cornish boilers in which one
or more large fire tubes extend from the one end of the boiler to the other, and it
consists principally in arranging within each of the said fire tubes, lengthwise
therein an additional boiler or vessel, extending as far as possible along the fire
tube but of smaller diameter than the latter and supported so as to leave an annular
space for the passage of the fire gases. This inner boiler or large water tube is
filled with water and is in communication with the main boiler at intervals by
means of short cross tubes extending direct across the annular fire gas space which
separates the inner boiler from the main boiler.
With this invention it is preferable to employ an outside firing by arranging the
furnace in front of the boiler in place of within the fire tube or tubes; by this
means the inner boiler may be extended further to the front in the fire tube than
would otherwise be the case.
The invention further contemplates the removal of ashes etc. from the annular
fire space before mentioned by means of steam jets arranged as described.
The invention is illustrated in the annexed drawings in which
Fig. 1 is a longitudinal section of a single tube Cornish boiler with outside firing
and fitted with the inner boiler the nature of which has been described. Fig. 2 a
horizontal central section thereof. Fig. 3 is a cross section.
A represents the fire tube of a Cornish boiler. B is the inner boiler or large
water tube therein. This inner boiler extends outward at the rear end of the fire
tube and through the brickwork at the flues at the back, and is provided at its
end with a removable plate or door for the purposes of cleaning. At its front end
it terminates in a conical or substantially conical plate with rounded point to
present the least amount of salient corners to the fire gases, which are divided and
pass along the sides of the fire tube around the inner boiler. The spent gases
divide at P and pass through flues arranged in the brickwork to the chimney.
To remove ashes and cinders which when carried along by the fire gases may
fall upon and rest on the top of the boiler B or also in the lower part of the fire
tube A, a steam pipes passes from the steam dome in a suitable manner to lie
along the upper surface of the boiler B and along the lower surface of the fire
tube A. This pipes is provided with branch pipes s¹ as shown and is perforated,
and the branch pipes also. A valve vis arranged at a suitable place in the pipe s,
on opening this valve, steam enters the pipes and issues from the perforations
blowing out the ashes which have collected in the neighbourhood of the pipe.
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
I claim is;-
In a Cornish boiler the combination with the fire tube A of an inner boiler
or water tube B arranged lengthwise therein to leave an annular space for passage
of the fire gases, the said inner boiler being connected to the main boiler by pipes
crossing the said annular space substantially as set forth.
2). In a Cornish boiler, the combination with the fire tube and an inner boiler
or water tube longitudinally arranged in said fire tube, of a steam pipes arranged

page_text: as described for the removal of ashes and other matters which may settle in the fire
tube or upon the water tube.
Dated this 20th day of June 1892.
HERBERT & Co.,
18, Buckingham Street, Strand, London, W.C., Agents to Applicant.