Improvements in Boiler Furnaces or Flues.
Year: 1892

page_text: Date of Application, 30th Nov., 1892
Complete Specification Left, 6th Dec., 1892-Accepted, 15th Apr., 1893
PROVISIONAL SPECIFICATION.
Improvements in Boiler Furnaces or Flues.
We, ANTHONY JOHN DAVISON, of Rosedale, Wallwood Road, Leytonstone in
the County of Essex, Consulting Engineer, and JOSEPH CHRISTOPHER JOBLING,
of Ventnor House, Leytonstone, in the same County, Engineer, do hereby declare
the nature of this invention to be as follows:-
This invention has reference to improved constructions of boiler furnaces or flues
(hereinafter referred to as boiler flues) that are capable of offering considerable
resistance to collapse whilst affording an efficient heating surface with small
liability to deposit of scale.
For this purpose the boiler flue is constructed for the greater part of its length
with a number of connected plain cylindrical portions, each alternate one of which
is of greater diameter than the remaining ones so that as seen in longitudinal section
the flue will be of crenellated form; or the portions of the flue plate of larger
diameter may be made of outwardly curved or circular shape in longitudinal section.
The portions of the flue having the larger diameter may be constructed with
external annular strengthening flanges.
In the accompanying drawings,
Fig. 1 shows partly in side elevation, and partly in longitudinal section one
construction of boiler flue according to this invention.
This flue, which is of circular form in cross section and is shown provided with
external strengthening ribs or flanges 1, is composed for the greater part of its
length of a number of short plain cylindrical portions 2 alternating with other
plain cylindrical portions 2b of larger diameter so that the flue is of crenellated form
in longitudinal section, the annular flanges 1 being formed on the portions 2b of
larger diameter. The ends of the flue may be enlarged as shown or be otherwise
suitably formed for attachment to a boiler, or boiler and combustion chamber as
well understood.
Fig. 2 is a similar view to Fig. 1 showing a slightly modified construction,
according to which the cylindrical portions 25 of the flue are made of greater
diameter relatively to the other portions 2" than in the construction shown in Fig. 1,
and the strengthening flanges 1 are dispensed with.
Fig. 3 is a side view partly in longitudinal section illustrating a construction of
boiler flue somewhat resembling that shown in Fig. 1 but in which the alternate
portions 2° of larger diameter and on which annular flanges 1 are formed, are each
of outwardly curved or circular form in cross-section so as to offer very great
resistance to collapse under the action of external pressure.
As will be seen boiler flues of the constructions shown and described, besides
offering considerable resistance to collapse, have no narrow pockets or receptacles
for accumulation of scale or deposit like corrugated boiler flues. They may
advantageously be each made by rolling down a metal plate of suitable dimensions
to either of the cross sections shown, then bending the plate to a cylindrical form,
and welding the adjacent edges together.
..
Nb1000

page_text: COMPLETE SPECIFICATION.
Improvements in Boiler Furnaces or Flues.
We, ANTHONY JOHN DAVISON, of Rosedale, Wallwood Road, Leytonstone in
the County of Essex, Consulting Enginer, and JOSEPH CHRISTOPHER JOBLING,
of Ventnor House, Leytonstone, in the same County, 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 has reference to improved constructions of boiler furnaces or
flues (hereinafter referred to as boiler flues) that are capable of offering con-
siderable resistance to collapse whilst affording an efficient heating surface with
small liability to deposit of scale.
For this purpose the boiler flue is constructed for the greater part of its length
with a number of connected plain cylindrical portions, each alternate one of which
is of greater diameter than the remaining ones so that as seen in longitudinal
section the flue will be of crenellated form; or the portions of the flue plate of
larger diameter may be made of outwardly curved or circular shape in longitudinal
section. The portions of the flue having the larger diameter may be constructed
with external annular strengthening flanges.
In the drawings filed with our Provisional Specification,
Fig. 1 shows partly in side elevation, and partly in longitudinal section one
construction of boiler flue according to this invention.
This flue which is of circular form in cross section and is shown provided with
external strengthening ribs or flanges 1, is composed for the greater part of its
length of a number of short plain cylindrical portions 2ª alternating with other
plain cylindrical portions 2° of larger diameter so that the flue is of crenellated
form in longitudinal section, the annular flanges 1 being formed on the portions 2"
of larger diameter. The jends 3 of the flue may be enlarged as shown or be
otherwise suitably formed for attachment to a boiler, or boiler and combustion
chamber as well understood.
Fig. 2 is a similar view to Fig. 1 showing a slightly modified_construction,
according to which the cylindrical portions 2b of the flue are made of greater
diameter relatively to the other portions 2ª than in the construction shown in
Fig. 1, and the strengthening flanges 1 are dispensed with.
Fig. 3 is a side view partly in longitudinal section illustrating a construction of
boiler flue somewhat resembling that shown in Fig. 1 but in which the alternate
portions 2b of larger diameter and on which annular flanges 1 are formed, are each
of outwardly curved or circular form in cross-section so as to offer very great
resistance to collapse under the action of external pressure.
As will be seen boiler flues of the constructions shown and described, besides
offering considerable resistance to collapse, have no narrow pockets or receptacles
for accumulation of scale or deposit like corrugated boiler flues. They may
advantageously be each made by rolling down a metal plate of suitable dimensions
to either of the cross-sections shown, then bending the plate to a cylindrical form,
and welding the adjacent edges together.
Having now particularly described and ascertained the nature of the said inven-
tion and in what manner the same is to be performed we declare that what we
claim is :-
A boiler flue composed for the greater part of its length of a number of short
plain cylindrical portions such as 2ª alternating with other portions such as 2° that
are of greater diameter than the portions 2ª and are either of plain cylindrical

page_text: form as in Fig. 1 and in Fig. 2, or of curved or circular form, as in Fig. 3, with
or without external strengthening ribs or flanges such as 1 substantially as
described and shown.
Dated this 5th day of Decembar 1900.
A. J. DAVISON,
By L. W., per F. B.
J. C. JOBLING,
By L. W., per F. B.