AN IMPROVED METHOD (OF FIXING AND UNFIXING THE TUBES OF STEAM BOILERS
Year: 1865

page_text: PROVISIONAL SPECIFICATION left by Samuel Soutar at the Office of the
Commissioners of Patents, with his Petition, on the 6th September 1865.
A communication from abroad by Daniel McDowell, of Kingston,
Jamaica.
I, SAMUEL SOUTAB, of Turnham Green, in the County of Middlesex, do
hereby declare the nature of the said Invention for "AN IMPROVED METHOD (OF
FIXING AND UNFIXING THE TUBES OF STEAM BOILERS," (a communication to me
from abroad by Daniel M Dowell, of Kingston, Jamaica,) to be as follows:...
This Invention relates to an improved method of fixing and unfixing the
tubes of steam boilers. It is a well known fact that a great many accidents
occur to boilers in consequence of the tubes being allowed to remain too long
without being taken out and cleaned, and the interior of the boiler properly
examined and if need be repaired, and it is generally admitted that the great
reason they are allowed to remain so long is owing to the expense incurred
by their removal and replacing. It is frequently the case that tubes which
are very little the worse, and would have lasted several years longer, have
been entirely or almost destroyed by taking them out, and in many instances
the tubes are allowed to remain until the steaming qualities of the boiler
are entirely destroyed rather than incur the expense of replacing them. By
the proposed arrangement the above-mentioned evils will be removed. In
the first place the tubes can be fitted in their places in less than one-quarter

page_text: of the time generally taken for such purpose, and in the next place they can
be made to fit both tube plates perfectly tight, so that there will be no danger
of cracking or bursting the ends in drifting them, which is very often the
case when tubes do not fit tightly into the tube plate. The greatest benefit
of all will be the facility with which the tubes can be taken out when required,
cleaned, and put back again. In carrying out this Invention one end of the
tube (the end next to the smoke box) is to be enlarged one-eighth of an
inch in diameter more than the rest of the tube, the enlargement to extend
about 1 inches from the end, which will be enough to allow a mandrill to
be applied to drift it up in the usual way. It will at once be seen that the
holes in the tube plate at the smoke-box end will be th of an inch larger than
those at the fire-box end; thus the tube entering from the smoke-box end will
pass through a hole th of an inch larger than itself until the last inch or
so, then it will enter the two plates tightly, and a blow or two of the hammer
will set it up to its place. It may be argued that this arrangement would
considerably weaken the tube plate at the smoke-box end by reducing the
spaces between the tubes th of an inch less than the other, but such will
not be case, as the plate at the smoke-box end is not exposed to the direct
action of the fire as is the plate at the fire-box end, therefore there is no
necessity for its being the same strength; but admitting that it does weaken
it, it will be easy to add as much to the thickness of the plate as would give
it the same sectional area as the other. The Inventor considers th of an
-inch enlargement is enough for the largest tube, and not too much for the
'smallest, as that will allow of the tube being incrusted to the extent of th
of an inch on the surface (one-eighth on the diameter), which is quite as
much as should be allowed to accumulate on any tube before it is taken out
especially where economy of fuel is an object. Any person who is acquainted
with the repairs of tubular boilers will see at once the advantages which this
system of tubing presents.