Improvements in Sectional or Water Tube Steam Boilers.
Year: 1889

page_text: Date of Application, 24th Jan., 1889
Complete Specification Left, 12th Oct., 1899-Accepted, 16th Nov., 1839
PROVISIONAL SPECIFICATION.
Improvements in Sectional or Water Tube Steam Boilers.
I GEORGE TANGYE of the firm of Tangyes Limited of Cornwall Works Soho
in the County of Stafford Engineers do hereby declare the nature of this Invention
to be as follows:-
In sectional or water tube steam boilers as ordinarily constructed great incon-
venience arises in consequence of leakage at the junction of the "headers" or boxes
(to which the tubes of the boiler are connected) with the steam drum at the top of the
boiler and with the mud drum at the bottom of the boiler.
My said invention has for its object principally to remedy the defect referred to and
to produce a boiler simple in construction practically free from leakage and economical
in the production of steam. Boilers constructed according to my said invention may
be transported in parts of little weight which parts can afterwards be readily put
together with but little aid of skilled workmen.
My said invention consists in constructing certain parts of the said boilers in the
ways hereinafter described.
33
constructing the "headers" or nearly vertical channels or boxes into which the
parallel rows of tubes open I employ straight tubes square or rectangular in cross
section. I make these tubes of steel or iron but preferably of steel the said tubes
either being solid drawn that is without weld or made from welded plates. When I
use steel I prefer solid drawn tubes when I use iron welded tubes may be conveniently
employed. The lower end of the "header" in communication with the steam chest is
closed the upper end being opened and fixed in the manner hereinafter described in an
opening in the steam drum. The upper end of the "header" opening into the mud
drum is closed and the lower open end is fixed in the mud drum in the manner
hereinafter described.
The open end of each "header" may be contracted into a cylindrical or slightly
tapering figure or separate contracted and tapering junction pieces may be fitted to
and fixed in the open ends of the square or angular "headers." The said separate
junction pieces may be fixed on the headers by riveting or otherwise.
In order to effectually fix the contracted ends of the "headers" in the steam drum
and mud drum respectively so as to avoid the leakage attendant on the ordinary
method of fixing them 1 proceed as follows. I give to the drum at each place where
a "header" is to be fixed. a double thickness of metal by riveting or otherwise fixing
to the said part a disc of sheet metal preferably of about three times the diameter of
the contracted ends of the "headers." I prefer to make the metal of the drum
concave around each of the holes in which a "header" is fixed and I make the disc
referred to either flat or of concavity less deep than the concavity in the drum. By
this arrangement the two thicknesses of metal are separated and the contracted end
of the "header" when in position has two bearings which not only give great rigidity
to the fixing thereby preventing the injurious action of strains by the expanding and.
contracting of the "header" but also give a double security against leakage.
Dated this 24th day of January.

page_text: COMPLETE SPECIFICATION.
Improvements in Sectional or Water Tube Steam Boilers.
I GEORGE TANGYE of the firm of Tangyes Limited of Cornwall Works Soho in the
County of Stafford Engineers do hereby declare the nature of my Invention and in
what manner the same is to be performed to be particularly described and ascertained
in and by the following statement :-
In sectional or water tube steam boilers as ordinarily constructed great incon-
venience arises in consequence of leakage at the junction of the "headers" or boxes
(to which the tubes of the boiler are connected) with the steam drum at the top of
the boiler and with the mud drum at the bottom of the boiler..
My said invention has for its object principally to remedy the defect referred to and
to produce a boiler simple in construction practically free from leakage and economical
in the production of steam. Boilers constructed according to my said invention may
be transported in parts of little weight, which parts can afterwards he readily put
together with but little aid of skilled workmen.
"
My said invention consists in constructing certain parts of the said boilers in the
ways hereinafter described.
In constructing the "headers
or nearly vertical channels or boxes into which the
parallel rows of tubes open I employ straight tubes square or rectangular in cross
section. I make these tubes of steel or iron but preferably of steel the said tubes.
either being solid drawn, that is, without weld or made from welded plates. When I
use steel I prefer solid drawn tubes; when I use iron welded tubes may be conveniently
employed. The lower end of the "header" in communication with the steam chest
is closed the upper end being open and fixed in the manner hereinafter described in
an opening in the steam drum. The upper end of the "header" opening into the
mud drum is closed and the lower open end is fixed in the mud drum in the manner
hereinafter described.
.
The open end of each "header" may be contracted into a cylindrical or slightly
tapering figure or separate contracted and tapering junction pieces may be fitted to
and fixed in the open ends of the square or angular "headers." The said. separate
junction pieces may be fixed on the headers by riveting or otherwise.
In order to effectually fix the contracted ends of the "headers" in the steam drum
and mud drum respectively so as to avoid the leakage attendant on the ordinary
method of fixing them, I proceed as follows. I give to the drum at each place
where a "header" is to be fixed a double thickness of metal by riveting or otherwise
fixing to the said part a disc of sheet metal preferably of about three times the diameter
of the contracted. ends of the "headers." I prefer to make the metal of the drum
concave around each of the holes in which a "header" is fixed and I make the disc
referred to either flat or of a concavity less deep than the concavity in the drum. By
this arrangement the two thicknesses of metal are separated and the contracted end of:
the "header" when in position has two bearings which not only give great rigidity to
the fixing thereby preventing the injurious action of strains by the expanding
and contracting of the "header" but also give a double security against leakage.
I will now proceed to describe with reference to the accompanying Drawings the
manner in which my invention is to be performed.
Figure 1 represents in longitudinal vertical section a sectional or water tube boiler
containing the improvements constituting my invention and Figures 2 and 3 represent
transverse sections of the same taken at opposite ends of the boiler; Figure 4
represents partly in cross section and partly in front elevation a portion of the boiler
drawn to a larger scale the said Figure 4 exhibiting the method of connecting the
front headers or boxes to the steam drum or dome and Figure 5 represents a section
of the steam drum or dome and one of the headers and the water tubes opening into
it taken in a plane at-right angles to that in which the section of Figure 4 is taken.
The same method of connecting the front headers or boxes with the steam chest or
'

page_text: drum is also applicable as hereinafter described to the connecting of the back headers
to the mud drum.
The same letters of reference indicate the same parts in the several Figures of
the Drawings.
a a a are the parallel front headers or boxes closed at bottom and open at top the
open tops being fitted into the bottom of the steam chest or dome c and 6 (see
Figure 1) are the back headers or boxes of a nearly similar construction closed at
top and open at bottom the said open bottoms being fitted into the top of the mud
drum d. Into each of the front and back headers ab the ends of a series of eight*
(or more) water tubes e e are fitted and expanded (see Figures 4 and 5) the several
rows of water tubes ee being parallel. The tubes e e of each row are arranged one
above the other in a vertical plane and the tubes are arranged side by side. in the same
plane, that is, opposite to each other as seen in Figure 4. Each of the parallel
headers a and b is made of a straight tube square or rectangular in cross section (see
the cross section of one of the headers in Figure 4) the tubes from which the
headers are made being either solid drawn or made from welded plates. The open
end of each header does not open directly into the steam dome (or mud drum) but
a separate contracted or slightly tapering piece or neck d' is fitted in and fixed by
rivetting to the open end of the header and the contracted part of the said neck
is fitted into the steam dome (or mud drum). The base of each separate contracted
piece or neck d is square or angular to fit in the square or angular header but
the upper part of the contracted piece or neck d² is cylindrical to fit in the
circular hole in the steam drum (or mud drum). Instead of making the contracted
ends or necks d separate from the headers they may be made in one piece with
the headers by shaping the open ends of the headers.
We fix the contracted ends or necks ď of the headers a in the steam drum or
dome c (or mud drum) in the following manner. Across the steam drum or dome c
at the place where the several headers are to be fixed a trough shaped depression
or pocket is made by a stamping or pressing process, the metal of the dome
being pressed inwards as best seen in the section Figure 5. Under the trough
shaped depression a separate plate 9 is rivetted at its edges and ends to the
dome c the middle of the said plate g having a depression of the same shape as but
shallower than that marked made in the bottom of the steam dome but a flat plate
instead of the trough plate g represented in the Drawing may be used. There is
thereby produced two thicknesses of metal separated a short distance apart and the
contracted ends or necks of the headers a are fitted in holes and expanded in the
holes made in the two thicknesses of metal as best seen in Figures 4 and 5. Two
bearings for the contracted ends or necks d² of the headers a are in this way made
which double bearings give great rigidity to the fixing and prevent the injurious
action of strains by the expanding and contracting of the headers and also give a
double security against leakage.
Instead of producing a double thickness of metal in the steam dome by making a
continuous trough shaped depression extending from side to side of the said dome
and rivetting a trough shaped or flat plate under the said depression as described
and represented the double thickness of metal may be produced by making a con-
cavity in the steam dome around each of the holes in which a header is fixed and
rivetting a disc either flat or with a concavity less deep than that in the dome
under the said concavity in the dome but I prefer to use the arrangement described
and shown in the drawings.
I connect the contracted ends or necks d of the back headers b to the mud
drum d by fixing them in a double thickness of metal the said double thickness
of metal being produced in either of the ways hereinbefore described and illustrated
with respect to the connecting of the contracted ends or necks of the front headers a
to the steam drum or dome c.
I am aware of Knight's Specification No. 17804 of 1888 and I claim nothing
described or claimed therein.

page_text: Having now particularly described and ascertained the nature of my inven-
tion and the manner in which the same is to be performed I declare that I claim
as: my invention of "Improvements in sectional or water tube steam boilers" :-
The methods herein before described and illustrated in the accompanying Drawings
of connecting the front headers to the steam dome or drum and the back headers
to the mud drum of the said boilers; that is to say, forming a double thickness
of metal at the parts where the headers are to be connected to the steam drum
or dome and mud drum and the production thereby of a double bearing for the
contracted ends or necks, of the said headers for the purposes and substantially as
herein before described and illustrated.
Doted this: Fighth date of On
-1980