An Improved Water Tube Boiler.
Year: 1897

page_text: An Improved Water Tube Boiler.
I, WILLIAM EDGAR BERRY, of 172 Great Clowes Street Higher Broughton,
Manchester, Engineer, do hereby declare the nature of this invention to be as
follows: :-
This invention relates to an improved water tube boiler.
In carrying out my invention may employ three drums which form the base
of the boiler connected together by several rows of tubes, which tubes may be
either curved or straight as desired; or a combination of straight and curved
tubes may be employed. I also provide a single steam drum situated above the
three bottom drums and connected to each other by one, two, three or more rows
of tubes which also may be either curved or straight; or a combination of straight
and curved tubes may also be employed.
The bottom drums are mounted at a suitable distance from the ground to enable
the fire grates to be situated between the drums and below the tubes connecting
them; a fire brick lining being placed above the tubes.
By this arrangement therefore, the products of combustion are caused to pass
the whole length of the drums and around the connecting tubes until they join in
a common combustion chamber situated at the back of the boiler from whence
they return, between the spaces formed by the tubes connecting the steam drum
to the bottom drums, to the front of the boiler, and thence into the flues.
Several of the rows of tubes connecting the steam drum to the lower drums
might also be bent or crossed to intercept the gases, or firebrick deflectors might
be used to lengthen the time that the gases are in contact with the tubes.
Or I may lengthen the contact of gases with the tubes by taking the gases from
both furnaces to a small chamber at the back of the boiler having an opening
communicating with one of the spaces formed by the rows of tubes connecting the
three lower drums to the steam drum, so that the gases will come to the front of
the boiler along that space and return to the back by the other space formed by
the tubes.
Of course either space may be used for conveying the gases to the front of the
boiler, depending upon the requirements, suitable brickwork being erected for
this purpose.
The intercepting tubes or firebrick deflectors first described may also be used
with this form of draught.
The first method or what I would term the direct draught may be used where
quick steam raising is a necessity. The second method or wheel draught may be
used where economy is the first consideration. Or a third method would he
obtained by combining methods one and two, this being carried out by
suitable dampers fixed in position, so that either methad one or method two may
he adopted at will in the firing of the boiler, thus providing for the various con-
tingencies of steam making.
A mud drum may be used at the back end of the boiler or a blow off pipe and
cock may be attached to each of the three drums.

page_text: For a medium sized boiler the three bottom drums may be connected to two
steam drums, these steam drums being connected on the steam and water sides by
tubes. The tubes connecting the steam drums to the lower drums may be
arranged as before described and the draught employed may be arranged on
similar lines as in the smaller type, that is to say, coming from the back to the
front along the two outer spaces formed by the tubes and returning to the back by;
the central space and vice versa. The wheel draught described may also be
employed or the combination of straight and wheel draught as previously
described.
Or for a large size boiler the three bottom drums may be connected to three
steam drums in a similar manner, and the same systems of draught adopted.
I may also apply a steam superheater at the back end of the boiler where the
gases are hottest instead of a brick deflector or keep the deflector in position and
fix the superheater in the combustion chamber and thus reduce the loss by radia-
tion. The tubes of the superheater may be placed either vertically or horizontally
and be connected to the steam drum or drums by the necessary valves and pipes
to regulate the superheating. At the outlet end or along the outside rows of tubes
but a little distance away, a series of tubes to heat the feed water may be placed.
It is to be understood however, that I do not limit myself to the precise conṛ
struction and arrangement of the drums and tubes, steam superheater and feed
water heater described, as it is obvious that they can be easily varied without
departing from the scope of my invention.
Dated this 26th dox of Tonn
1807
JOHNSONS,
Petitioner's Agents, 115 St. Vincent Street, Glasgow.
I, WILLIAM EDGAR BERRY, of 172 Great Clowes Street, Higher Broughton,
Manchester, Engineer, do hereby declare the nature of this invention, and in
what manner the same is to be performed, to be particularly described and ascer-
tained in and by the following statement:-
'
A
This invention relates to an improved water tube boiler.
But in order that my said invention may be more readily understood and easily
carried into effect I will proceed to describe the same with reference to the accom-
panying drawings in which
Fig. 1 is a sectional elevation.
Fig. 2 a sectional end elevation.
Figs. 3 and 4 are similar views of the boiler but having the mud drums all of
the same or nearly the same diameters and the addition of a superheater and feed
water heater.
•
Figs. 5 & 6 are similar views of a modification and
Figs. 7 & 8 are similar views of a further modification.
Referring to Figs. 1 and 2 of the said drawings. the boiler is. composed
fundamentally of three mud drums M1 M2 M³ mounted at some distance. apart and
connected to each other by one or more rows of straight or curved tubes TT,
preferably the former.
-
These three mud drums M¹ M² M³ which may be of different diameters are
connected to one common steam drum S. D as shewn in Figs. 1 and 2; the con-
nections between the steam and the mud drums being made by either straight
or curved tubes T¹ T¹, preferably the former..
The grates G G which are two in
f
number are placed at the proper distance

page_text: below the tubes T T connecting to the three mud drums M1 M2 M3 thus overcoming
the principal objection to the use of water tube boilers for Marine and Land work
viz the amount of water storage above the parts immediately exposed to the action
the fires and at the same time adding to the efficiency of the boiler by taking
fuller advantage of the convection currents. The tubes T T by reason of their
position are more liable to require replacement than the rest of the tubes in the
boiler. Special arrangements are therefore made for replacing them expeditiously.
The middle mud drum M2 may be made of such a diameter, that the tubes T T
can be withdrawn into it and replaced from it. Access to this mud drum being
provided in the usual way by means of a manhole placed preferably in either end
of it. Or as shewn in Figs. 3 & 4 the middle drum M2 may be made equal in
diameter or slightly larger or smaller than the outer mud drums M, and M³.
Where this method of construction is adopted, the drums M', & M³ may be mado
in two parts and bolted together or a series of holes may be drilled at H H coaxial
with the tubes and the tubes entered from these; the holes being fitted with screw
plugs or covering flanges or the tube holes in one of the mud drums may be
enlarged to such a size that the tube may be placed in the larger hole and angled
into position. The tube end being fitted with a ferrule of ductile material and
tube end and ferrule expanded together into the drums. Or the tubes may have a
short enlarged part to fit into the drum with the larger holes.
The products of combustion are led from the grates G G amongst the tubes to the
back end of the boiler and where a quick steaming boiler is a necessity, these may
pass to the front of the boiler and away to the chimney or funnel through the
opening F, deflectors D D of suitable material may be placed as shewn to obstruct
the passage of the gases i.e. to lengthen the time in which the gases will be in
contact with the heating surfaces. Tubes may also be bent for this purpose. In
other cases where economy is a consideration the products of combustion may pass
to the back end of the boiler to a small chamber C Fig. 1 having an opening to one
of the spaces S¹ S² formed by the tubes connecting the three lower drums to the
steam drum S D so that the gases may pass to the front of the Boiler along that
space and return to the back end by the other and thence to the chimney. Either
space may be used for conveying the gases to the front end of the boiler depending
upon local requirements, suitable brickwork being erected for this purpose. The
intercepting tubes or deflectors will also he used with this form of draught.
The first method or direct draught and the second method or wheel draught may
be combined by placing suitable dampers so that either method may be used at will
to suit the requirements of steam raising. Where the feed water carries a larger
amount of solids in suspension a smaller mud drum may be used, this will be
placed at right angles to the existing mud drums and connected to them below at
the back end; a suitable blow off pipe and cock being provided. Or blow off pipes
and cocks may be fitted at either end of the mud drums M' M² M³.
The chief losses in water tube boilers are those due to radiation and in the escape
of gases at a comparatively high temperature to the chimney or funnel.
A superheater SH Figs. 3 & 4 is provided to reduce the former, this is pro-
vided with the necessary valves to regulate the amount of the superheat. The
radiant heat may be further absorbed by providing a sheet metal covering to the
boiler as shewn on the left hand portion of sectional end elevation Fig. 2. The
whole of the passage P (which might be provided on the other side of the boiler as
well) is utilized for the heating of the air supplied to the furnaces. In Figs. 3, 4
5 & 6 only part of the space provided is used, while to reduce the temperature of
escaping gases feed heaters F H Figs. 3, 4, 5 & 6 may be fitted.
As a modification the boiler may consist as shewn in Figs. 5 & 6 of three mud
drums M, M2 M3 mounted at some distance apart and connected to each other by
one or more rows of straight or curved tubes T T, preferably the former.
These three mud drums M1 M2 M3 are connected to two steam drums S¹ D¹, S² D².
The connections between the steam and the mud drums are made by either straight
or curved tubes T¹ T¹ preferably the former, while the steam drums are connected

page_text: together both on the steam and the water sides by straight or curved tubes or a
combination of bent and straight tubes T2 T³.
The mud drums may be made all of one size or of different sizes as fully set
forth with regard to Figs. 1 to 4. The draught may also be arranged on the samo
principles as therein described on the direct and also on the wheel draught system
in which case the gases may be brought to the front of the boiler by the
spaces S1, S2 and returned to the back by the central space $3 or vice versa, or on
the combination method, while a superheater and feed water may be applied to
reduce the losses previously described. The air supplied to the furnaces may be
also heated, as previously described.
A further modification of my improved water tube boiler consists of three mud
drums M1 M2 M3 as shewn in Figs. 7 and 8 mounted as previously described and
connected with tubes to three steam drums S¹, D¹, S2 D2, S3 D³. These steam
drums being connected together by one or more rows of tubes on the steam sides
and water sides, these tubes T2 Ta being bent or straight or bent and straight
The mud drums M1 M2 M³ may be all of one size or of different sizes as before.
The draught may be arranged on the system first described and a superheater,
feedwater heater and arrangement made for the heating of the air, may also be
applied if desired.
Having now particularly described and ascertained the nature of my said
invention and in what manner the same is to be performed, I declare that what
I claim is: -
1. In water tube boilers, the arrangement of the steam and mud drums sub-
stantially as hereinbefore described and shewn in Figures 1, 2, 3, and 4 of the
accompanying drawings.
2. In water tube boilers, the modified arrangement of the steam and mud drums,
substantially as hereinbefore described and shewn in Figures 5 and 6 of the
accompanyin drawings.
3. In water tube boilers, the modified arrangement of the steam and mud drums,
substantially as herein before described and shewn in Figs. 7 and 8 of the accom-
panying drawings.
4. In water tube boilers, the arrangement and position of the fire grates
relatively to the mud drums, substantially as herein before described and shewn
in the accompanying drawings.
5. In water tube boilers, the arrangement of the draught, either direct or on the
wheel system or a combination of both, substantially as hereinbefore described and
shewn in the accompanying drawings.
6. In water tube boilers, arranging the superheater, feedwater heaters and air
supply heating passage, substantially in the manner as herein before described and
shewn in the accompanying drawings.
Doted this 26th day of Octation 1007
JOHNSONS,
Applicants Agents 115 St. Vincent St. Glasgow.