Improvements in Tubulous Boilers.
Year: 1894

page_text: Date of Application, 6th June, 1894
Complete Specification Left, 6th Mar., 1895-Accepted, 6th Aor., 1895
PROVISIONAL SPECIFICATION.
Improvements in Tubulous Boilers.
We, DAVID PURVES, of Wyborne Gate, Birkdale, Southport, and ALFRED
BLECHYNDEN, of Cavendish Park, Barrow in Furness, both in the County of
Lancaster, Engineers, do hereby declare the nature of this invention to be as
follows:-
:-
Our invention has reference to certain improvements in tubulous boilers.
It relates principally to boilers having an upper horizontal steam and water chamber
and two lower horizontal water chambers or drums which are connected to the
upper by groups of sloping or upright tubes.
In one form of boiler constructed according to our invention we arrange for a
part of the length sloping water tubes of comparatively large diameter to form a
close wall on each side of the fire grate either by enlarging the central portions of
the tubes or contracting the ends or in other ways and we form either in the upper
steam and water chamber or about the rear of same a combustion chamber, a group
or groups of longer water tubes being employed to connect the lower drums with
the top of said chamber. We prefer also to form a close wall at the rear, of water
tubes of large diameter one end of each being secured at one end in the top of the
combustion chamber and at the other end in a small water drum connected to the
lower water drums while in the upper steam or water chamber and communicating
with the combustion chamber before mentioned are number of horizontally
arranged fire tubes or a flue to conduct the heat and gases to the chimney.
In another arrangement instead of forming the sloping water tubes as a close
wall we arrange them with interstices between them for the heat and flames from
the grate to pass through (though preferably still employing them of larger
diameter in the centre than at the ends) and at the back of the fire grate we form
a wall of refractory material up to the bottom of the upper chamber thus causing
the gases to pass through the sloping tubes into a combustion chamber formed
between them and a close row of longer water tubes formed on each side of the
length or a portion of the length of the boiler some of said tubes being secured to
flanges or ears formed on the side of the upper steam and water chamber so that
they communicate with same (or they may be otherwise connected to same) while
the others are secured to the top of the combustion chamber formed on said upper
steam and water chamber.
In another arrangement we form a combustion chamber in the upper steam and
water chamber which communicates with a combustion space behind the wall of fire
resisting material if such is employed by means of short tubes or necks through
which the gases pass.
In another arrangement instead of the short tubes last mentioned communicating
with a combustion chamber which in turn communicates with tubes, the short tubes
may communicate with a flue which runs the length of the upper water and steam
chamber, or in place of the central flue cross tubes may be arranged in the upper
chamber so that the gases can pass through same from the combustion spaces formed
between the sloping tubes and the close row of tubes outside of same.
In another form we may employ. two or more flues in the upper chamber instead
of a single fluc such flues being connected by necks or tubes to the combustion
chambers at the end of the furnace or at the sides of same and we may employ
with this or with any of the arrangements above described two or more rows of

page_text: sloping tubes connecting the lower water chamber with the upper such tubes being
arranged with interstices between them at the top and bottom respectively so that
the gases are compelled to take a tortuous course through them. With this
arrangement an outer wall of water tubes is preferably employed.
In place of a single upper steam and water chamber we may construct the boiler
with two or more of same and connect them by tubes with two or more lower water
chambers.
Dated thie 6th day of June 1894
We, DAVID PURVES, of Wyborne Gate, Birkdale, Southport, and ALFRED
BLECHYNDEN, of Cavendish Park, Barrow in Furness, both in the County of
Lancaster, Engineers, 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 :-
Our invention has reference to certain improvements in tubulous boilers.
It relates principally to boilers having an upper horizontal steam and water
chamber and lower horizontal water chambers or drums which are connected to the
upper by groups of sloping or upright tubes.
To clearly explain our invention we will describe it with reference to the
accompanying drawings.
In one form of boiler constructed according to our invention and illustrated at
Figs. 1 and 2 we arrange for a part of the length of same sloping water tubes a of
comparatively large diameter to form a close wall on either side of the fire grate
either by enlarging the central portions of the tubes or contracting the ends or in
other ways such tubes connecting the lower drums with the upper steam and
water drum c and we form either in the upper steam and water chamber c or about
the rear of same a combustion chamber d, a group or groups of longer water tubes e
being employed to connect the lower drums with the top of the chamber d. We
prefer also to form a close wall at the rear, of water tubes of large diameter one
end of each being secured in the top of the combustion chamber d and at the other
end in a small auxiliary water drum g connected to the lower water drums in some
suitable way such as by tubes h while in the upper steam or water chamber c and
communicating with the combustion chamber before mentioned are a number of
horizontally arranged fire tubes i or a flue to conduct the heat and gases to the
chimney. The space between the tubes a and e may be closed by metal plates or
fire brick walls or by other suitable means.
In the arrangement illustrated in Figs. 3 and 4 instead of forming the water
tubes a as a close wall we arrange them with interstices between them for the heat
and flames from the grate to pass through (though preferably still employing them
of larger diameter in the centre than at the ends) and at the back of the tire grate
we form a wall of refractory material up to the bottom of the upper chamber c
thus causing the gases to pass, through the tubes a into a combustion chamber
formed between them and a close row of longer water tubes m formed on each side
of the length or a portion of the length of the boiler said tubes being secured to
flanges or ears n formed on the side of the upper chamber e so that they com-
municate with same or they may be otherwise connected to same as by the tubular
chamber n' Figs. 5 to 12 or by bending the tubes as at n² Fig. 7 while the other
tubes e are secured to the top of the combustion chamber d formed in the upper

page_text: chamber c. In place of the refractory wall k we may employ a wall formed of
close tubes such as connected to a drum such as g.
In the arrangement shown in Figs. 5 and 6 we form a combustion chamber d¹ in
the upper steam and water chamber which communicates with a combustion space
behind the wall of fire resisting material (if such is employed) by means of short
tubes or necks o through which the gases pass.
The gases also after learing the chamber may pass into the combustion
chamber d by means of short tubes por further necks such as o may be employed.
The boiler shewn in these figures is double ended the firing taking place from
both ends and the necessary parts being duplicated.
In the arrangement shewn in Figs. 7 and 8 instead of the short necks or tubes
last mentioned communicating with a combustion chamber which in turn com-
municates with tubes, the short tubes p, or it may be necks such as o, may
communicate with a flue 9 from the combustion chambers which run the
length of the upper chamber c or in place of the central flue √ cross tubes may be
arranged in the upper chamber such as would be seen if the flue q were removed
and the cross tube (or flues) were extended so as to cross the diameter of the
chamber e the gases passing through same from the combustion spaces and passing
out to a flue formed on the upper side of the chamber c, or the tubes or flues may
be arranged in other ways.
Or we may employ two or more flues such as y in the upper chamber instead of
a single flue such flues being connected by necks or tubes to the combustion
chambers d at the end of the furnace or the chambers at the sides of same and we
may employ with this or with any of the arrangements above described except
where a close wall is required two or more rows of sloping tubes connecting the
lower water chamber with the upper such tubes being arranged with interstices
between them at the top and bottom respectively so that the gases are compelled
to take a tortuous course through them. Such an arrangement shown in Figs. 9
and 10 where four rows of tubes a are employed two being of smaller diameter than
the others. A baffle or apron plater may also be employed in order to prevent
the gases passing away too quickly.
In the arrangement shown in Figs. 11 and 12 the combustion chamber d is shown
as being formed by a walls of fire resisting material built out from the boiler the
upper steam and water chamber c being a plain tubulous boiler or it may be a flue
boiler.
In place of a single upper steam and water chamber we may construct the boiler
with two or more of same and connect them by tubes with two or more lower water
chambers.
Having now particularly described and ascertained the nature of our said inven-
tion and in what mauner the same is to be performed we declare that what we
claim is :-
1. The construction of tubulous boiler having sloping or upright tubes connecting
water drums with a steam and water chamber provided with fire tubes or a flue or
flues, a combustion chamber being provided between the grate and the fire tubes
substantially as described.
2. The construction of tubulous boilers having sloping or upright tubes connecting
water drums with a steam and water chamber provided with a flue or flues,
connected to combustion chambers on the outsides of the upright or sloping tubes
by means of short tubes or necks substantially as described.
3. The construction of tubulous boiler having sloping or upright tubes connecting
water drums with a steam and water chamber provided with fire tubes or flues,
connected with combustion chambers on the outside of the upright or sloping tubes
substantially as described.
4. The construction of tubulous boiler having sloping or upright tubes connecting
water drums with a steam and water chamber provided with fire tubes or a flue or
flues, and a combustion chamber formed in or partly in or at the rear of the steam

page_text: or water chamber and communicating with said tubes flue or flues substantially as
described.
5. The employment with tubulous boilers of the type described of a wall at the
end of the fire grate and a row or rows of tubes enclosing said fire grate and
having interstices between them substantially as and for the purpose set forth.
6. The employment with tubulous boilers of the type described of a close wall of
tubes connecting the upper steam and water drum with an auxiliary water drum
substantially as described.
==
7. The various arrangements or constructions of tubulous boilers substantially as
described and illustrated in the drawings.
Dated the 6th day of March 1895.
PHILIP M. JUSTICE,
55 & 56, Chancery Lane, London, Chartered Patent Agent,
For the Applicants.