Improvements in and relating to the Tubes of Steam Boilers.
Year: 1897

page_text: Date of Application, 6:h May, 1897-Accepted, 12th June, 1897
COMPLETE SPECIFICATION.
Improvements in and relating to the Tubes of Steam Boilers.
I. WILLIAM SAYER of "The Mount," Uttoxeter Road, Derby in the County of
Derby, 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 :-
The object of my invention is to effect certain improvements in and relating to the.
tubes of steam boilers working on what is generally known as the flashing system,
that is to say where a small quantity of water only is admitted to the tubes at a time
and converted into steam as it circulates through them; my said improvements being
designed to provide as large a heating surface of tube as possible combined with the
best form to resist pressure when highly heated, and, at the same time to reduce the
capacity of the tubes for holding water to a minimum, to provide means for absorbing
and storing the heat as will be hereinafter explained and also to provide ready access
to the tubes for cleaning purposes.
In describing my invention reference will be had to the accompanying sheet of
drawings, similar letters of reference indicating corresponding parts.
Figure 1 is a longitudinal section or plan on line a. a. of Figure 2 through two
tubes constructed according to my invention.
Figure 2 is a cross section on line b. b. of Figure 1.
In carrying out my said invention I form each tube A of a circular cross section
and arrange a central core B inside same leaving an annular space D between the
core and the tube, any suitable fixing devices such as E, E, being employed for fixing
the core centrally of the tube. The nut F securing the piece G and holding the
core in position the said piece G being threaded at the end G¹ for convenience
in fixing connections from one tube or set of tubes to another outside the
fire-box.
The cores or centre pieces B may be of any light metal having good heat absorbing
and storing properties such as aluminium, or, they may be made hollow and of any
other metal if desired.
Boilers may be made up of any number of these tubes arranged inside a suitable
fire-box or furnace each tube end communicating horizontally or vertically with the
next; the water being admitted or forced in small quantities as desired in the lower
tube or tubes and circulating upwards in the direction of the arrows from one tube
or set of tubes to the next through the whole of them, and being converted into
steam on its way through them. All the internal spaces of the boiler being kept
as small as possible to effect the rapid conversion of the water into steam.
Cores may also be arranged in the bends A' if desired although to avoid
complicated parts I prefer to simply reduce the diameter of the bends so that
their sectional area will correspond or be in proportion to that of the annular space
between the core and the main tube as illustrated.
It will be evident that a boiler constructed as herein described may be made very
light in proportion to its power, which advantage combined with the simplicity of
working on the flashing system will make it particularly adaptable to purposes where
great power, simplicity and lightness are the great considerations.

page_text: Having now particularly described and ascertained the nature of my said inven-
tion and in what manner the same is to be performed I declare that what I
claim is
The improvements in and relating to the tubes of steam boilers consisting of
en ploying tubes of a circular cross section in combination with a central core having
an annular space between each core and tube substantially as and for the purposes
described and illustrated.
Dated this 5th day of Mov 1907
W. SWINDELL,
Imperial Chambers, Albert Street, Derby, Agent for the Applicant.