Improvements in or relating to Boiler Tubes for Steam Boilers.
Year: 1890

page_text: Date of Application, 5th June, 1890
Complete Specification Left, 5th Mar., 1891-Accepted, 5th June, 1891
PROVISIONAL SPECIFICATION.
Improvements in or relating to Boiler Tubes for Steam Boilers.
I, TOMMASO AGUDIO of 95 Bd Beaumarchais, Paris in the Republic of France,
do hereby declare the nature of this invention to be as follows:-
The object of this invention is to improve the heating apparatus of steam boilers
fitted with suction pipes by a novel arrangement of boiler tubes which is an improve-
ment upon what is known under the name of the Tenbrinck system.
When applied to the fire-box of a locomotive engine (which is the purpose for
which these improvements are mainly intended although of course they are
applicable with equal advantage to steam boilers of other descriptions), the boiler
tubes connected according to this improved system are no longer arranged vertically
as in the principal Patent but are almost parallel to the plane of the grate. They
are of cylindrical or semi-elliptic section the gases generated by combustion being
by such an arrangement caused to flow round the fire-box, without preventing a
portion of such gases from passing through the spaces between the tubes.
Each tube instead of joining directly the walls of the fire-box or boiler is
connected at each end to a collecting pipe which pipes in their turn are connected
with the boiler by junction pieces or tubes.
The method of fitting together the Tenbrinck boiler tubes and the collecting
pipes is the same as that generally adopted for connecting tubes with the tube
plates; but in counter-sinking the circular orifices in the thickness of the walls
of the collectors, care should be taken to make such orifices slightly flaring
inwardly. A tight fit between the walls of the boiler tubes and the edges of
the surrounding orifices is obtained by means of a mandril passed into each of
the openings after the insertion of the tubes.
The advantages of this improved arrangement of boiler tubes may be summarized
as follows:-
1st. The heat concentration chamber of the ordinary Tenbrinck system is
retained above the grate.
2nd. The gases as they pass through the interstices between the boiler tubes
(which, by surrounding, they heat) are enabled to meet the main current thereby
producing the gaseous mixture necessary for promoting combustion.
3rd. The boiler tubes being set at certain distances apart prevents cinders
from falling down onto the back surfaces of the Terbrinck tubes which they
do in the ordinary arrangement, thus rendering the tubes less capable of
absorbing heat.
4th. The large amount of heat absorbed by these Tenbrinck boiler tubes
necessarily reduces the temperature of the gases to a great extent before the
latter come in contact with the tube plate which plate is thereby more effectively
protected as are also the longitudinal pipes.
5th. The very rapid currents of water caused by the lower collecting pipe in
the Tenbrinck tubes generates a general stir in the mass of water enveloping
the fire-box thereby rendering the walls of the latter capable of more thorough
action and less liable to injury from the fire.
6th. The large direct heating surface necessarily in a very great measure
assists the generation of steam the part it performs being in fact greater even
Owing to this fact
than that of the fire-box or of the whole series of tubes.
the length of the longitudinal boiler tubes may be reduced while retaining

page_text: practically undiminished the heating power of the boiler and considerably
increasing its power of generating steam.
Dated this 5th day of June 1890.
W. P. THOMPSON & BOULT,
Agents for the Applicant.
COMPLETE SPECIFICATION.
Improvements in or relating to Boiler Tubes for Steam Boilers.
[, TOMMASO AGUDIO of 95 Bd Beaumarchais, Paris in the Republic of France,
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 this invention is to improve the heating apparatus of steam
boilers fitted with suction pipes by a novel arrangement of boiler tubes which
is an improvement upon what is known under the name of the Tenbrink
system.
In the accompanying drawing
Figure 1 is a sectional eleration.
Figure 2 is a sectional plan of this arrangement of boiler tubes.
Figure 3 is a section of a Tenbrink boiler tube at its junction with a collecting
pipe, and
Figure 4 represents the same junction in a plan.
When applied to the fire box of a locomotive engine (which is the purpose for which
these improvements are mainly intended although of course they are applicable
with equal advantage to steam boilers of other descriptions), the boiler tubes a b
12 connected according to this improved system are not arranged vertically
but are almost parallel to the plane of the grate (Figs. 1 and 2). They are of
cylindrical or semi-elliptic section (Fig. 4) the gases generated by combustion
being by such an arrangement caused to flow round the fire-box without
preventing a portion of such gases from passing through the spaces between the
tubes.
Each tube a¹² 12 instead of joining directly the walls of the fire box
or boiler is connected at each end to a collecting pipe (Figs. 1 2 and 3) which
pipes in their turn are connected with the boiler by junction pieces or tubes C D
CDEFEF a³ are strengthening rivets.
The method of fitting together the Tenbrink boiler tubes a ba¹¹ a² b² and the
collecting pipes A B A B is the same as that generally adopted for connecting
tubes with the tube plates; but in countersinking the circular orifices c d c¹ d' e² d²
in the thickness of the walls of the collectors A B A' B', care should be taken to
make such orifices slightly flaring inwardly. A tight fit between the walls of the
boiler tubes and the edges of the surrounding orifices is obtained by means of a
mandril passed into each of the openings e fe' f' ef after the insertion of the
tubes.
The advantages of this improved arrangement of boiler tubes may be summarized
as follows:-
1st. The heat concentration chamber of the ordinary Tenbrink system is retained
above the grate.
2nd. The gases as they pass through the interstices between the boiler tubes a b
aab (which, by surrounding, they heat) are enabled to meet the main current
thereby producing the gaseous mixture necessary for promoting combustion.
3rd. The boiler tubes being set at certain distances apart prevents cinders from
falling down. onto the back surfaces of the Tenbrink tubes which they do in
the ordinary arrangement, thus rendering the tubes less capable of absorbing heat.

page_text: 4th. The large amount of heat absorbed by these Tenbrink boiler tubes
necessarily reduces the temperature of the gases to a great extent before the latter
come in contact with the tube plate which plate is thereby more effectively protected
as are also the longitudinal pipes.
5th. The very rapid currents of water caused by the lower collecting pipe in the
Tenbrink tubes generates a general stir in the mass of water enveloping the fire-
box thereby rendering the walls of the latter capable of more thorough action and
less liable to injury from the fire.
6th. The large direct heating surface necessarily in a very great measure assists
the generation of steam the part it performs being in fact greater even than that of
the fire-box or of the whole series of tubes. Owing to this fact the length of the
longitudinal boiler tubes may be reduced while retaining practically undiminished
the heating power of the boiler and considerably increasing its power of generating
steam.
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 improved arrangement of boiler tubes according to the Tenbrink system
consisting of a series of boiler tubes practically parallel to the grate with intervals
between them and connected by their ends to collecting pipes communicating
with the boiler, substantially as described and illustrated in the accompanying
drawings.
Dated this 5th day of March 1891
W. P. THOMPSON & BOULT,
Agents for the Applicant.