Improvements in Steam Generators.
Year: 1896

page_text: Improvements in Steam Generators.
I, JOHN SAMPSON, of 41 Effra Road, Brixton, London, S.W., Engineer, do
hereby declare the nature of this invention to be as follows:-
Amongst the characteristics recognised as desirable in a water tube steam
generator are (a) that it should be compact, light, cheap to manufacture, easily
accessible for cleaning and repairs; and should comprise separate interchangeable
sections or elements, adapted to be individually capable of easy removal and
replacement or substitution without disturbing other parts of the boiler; (b) that
regard being had to the high steam pressures commonly adopted, the boiler should
be composed, as far as possible, of tubes of relatively small diameters with the
view of more fully ensuring lightness, strength and immunity from disastrous
explosions, and that the ends of the tubes where they are attached to other parts
of the boiler should be rolled or expauded therein, union or flange joints being
liable to give trouble especially when exposed to extreme heat of fires under
forced draught; (c) that the construction should be such as to permit of any
defective tube being readily removed and a new one fitted without injury to or
removal of any other tube or part of the boiler; (d) that the furnace or firebox
should be such as to ensure a satisfactory combustion of the firegases with ordinary
coal and stokers; (e) that the arrangements for promoting combustion of fuel and
circulation of water should be such as not only to give satisfactory results at slow
speeds under natural draught but also to enable the boiler to be without danger
worked under forced draught as an express boiler, and that in this connection, the
tubes exposed to the greater heat should be ensured a plentiful supply of water;
(f) that the construction should be such as to obviate rigidity as also undue
strains such as are liable to arise owing to the extreme and rapid changes of
temperature and pressure to which water tube boilers are subjected; (9) that in
order to obviate as far as possible the considerable reduction in comparative
efficiency which is liable to occur from carbonaceous or other non conductive
deposits on the outer surfaces of the tubes of boilers of the type referred to after
they have been under steam for a relatively short period (especially when burning
bituminous coal) there should be provision for properly cleaning the tube surfaces
with facility and despatch whilst the boiler is under working pressure and the fires
are burning; and (4) that with the view of keeping the internal surfaces of the
tubes as free as possible from deposit means should be provided for effecting
purification of the water in the boiler in an automatic and continuous manner.
Now my invention has reference to an improved construction of sectional water
tube steam generator designed to fulfil the requirements above indicated. It
comprises a feed collector and a steam and water vessel I will call the steam drum,
which are connected by a number of curved tubes I will call furnace crown tubes,
and by a number of interchangeable sections or elements each of which comprises
a vertical or inclined header adapted to be secured by a cone, flange, spigot oz
other suitable joint or connection to the feed collector, a horizontal or inclined
header adapted to be connected in like manner by any suitable joint or connection
to the steam drum, and any convenient number of curved tubes which connect the
wo headers, the ends of the curved tubes being attached to the headers in some
uitable way, for example by being expanded therein. The headers can be

page_text: eylindrical, oval, rectangular or of other suitable cross section. In those sides-
of the headers opposite to the sides at which the ends of the curved tubes enter
them, there are provided plugs, screws or doors for the purpose of affording access
for examination, cleaning or removal of tubes, or for expanding tube ends. The
headers may be constructed of wrought or cast iron, or steel, or other suitable
material. They are arranged side by side in close contact thereby forming a front
and a crown to the boiler. The feed collector is fitted with plugs, screws or
suitable doors to afford access for the purposes of cleaning, examining, and
expanding the lower ends of the furnace crown tubes and for the removal of these
tubes whose upper ends are expanded into the steam,.drum. Below the.steam
drum is a vessel (herein called the sediment chamber) which is connected with the
steam drum by tubes (herein called downcast tubes) which may be of any con-
venient number and diameter arranged side by side, with their external surfaces
in mutual contact thereby forming a wall. The sediment chamber is fitted with
suitable baffles for the purpose of facilitating the separation of the impurities'
contained in the water. Pipes are provided connecting the sediment chamber with
the feed collector, one pipe being fitted at each side of the boiler. The horizontal:
or approximately. horizontal headers may be arranged to discharge the steam and
water into the steam drum either above the normal water level of the boiler, or
below, in which latter case an additional steam drum or chamber.may be provided."
The steam drum is fitted with suitable bafflers.
For the purpose of forming a furnace crown and diverting the passage of the
fire gases in order to ensure efficient combustion, firebricks or tiles are arranged
over the furnace crown tubes in such a way as to be easily removable and that their
number can be varied according to the rate of combustion required and the quality
of coal used, a door being fitted in the casing to enable this to be done. For the
purpose of regulating the quantity of water admitted to the furnace crown tubes
and the bent tubes of the sections of elements during the process of circulation in
the boiler, there are provided cone ferrules constructed of slightly larger diameter
than the said tubes and sprung into place, a gap being cut in the lower part of
each ferrule to ensure drainage of water from the tubes when the boiler is emptied.
These ferrules also serve to prevent reversal of the circulating current. For the
purpose of diverting the fire gases there is provided a baffling arrangement
comprising a horizontal shaft or spindle to which a number of V-shaped or
otherwise conveniently formed vertical bafflers are attached, the shaft or spindle
being so placed in the boiler that the bafflers fit in between the heating tubes
of the elements at the gaps formed between the elements, and suitable levers being
provided that can be worked from the outside whereby the angle of the bafflers
can be adjusted.
The heating tubes of the elements can be cleaned by steam jet in the usual
manner through the smoke box door, but in order that the external surfaces of the
said tubes may be more thoroughly cleaned, bearings are provided in a position
eccentric to the axis of the curve of the tubes to be cleaned; into these bearings
the spindle of a compound brush somewhat resembling a comb, with bristles on its
teeth, and which can be kept in the stokehold, can be shipped so that by means of
suitable levers the brush can be worked in an upward and downward direction
thereby sweeping the soot from the surfaces of tubes.
Feed water is injected into the steam drum and descends the downcast pipes into
the sediment chamber where the impurities are deposited, clean water rising over
the bafflers and through connecting pipes into the feed collector whence a portion of
it passes into the furnace crown tubes and thence into the steam-drum and a portion
into the vertical headers and thence by the curved tubes of the elements and the
horizontal headers into the steam drum. The water is separated from the steam
by means of the bafflers and again descends, together with the feed water, through
the downcast tubes into the sediment chamber and so forth. A blow-off pipe is
connected to the sediment chamber for the purpose of blowing out the sediment'or
water from the boilers.
j

page_text: The headers, steam drum, feed collector and sediment chamber are suitably
connected together by stay rods to prevent undue straining of the joints between.
the headers and the feed collector and steam drum by expansion of the tubes
connecting the headers.
My invention enables a large amount of tube heating surface to be conveniently.
fitted into a small space.
Improvements in Steam Generators.
I, JOHN SAMPSON, of 41 Effra Road, Brixton, in the County of London,
Engineer, do hereby declare the nature of this invention and in what mauder the
same is to be performed to be particularly described and ascertained in and by
the following statement :-
Amongst the characteristics recognised as desirable in a water tube steam
generator are (a) that it should be compact, light, cheap to manufacture, easily
accessible for cleaning and repairs, and should comprise separate interchangeable
sections or elements adapted to be individually capable of easy removal and
replacement or substitution without disturbing other parts of the boiler; (b) that,
regard being had to the high steam pressures commonly adopted, the boiler should
be composed, as far as possible, of tubes of relatively small diameters with the
view of more fully ensuring lightness,, strength, and immunity from disastrous
explosions, and that the ends of the tubes, where they are attached to other parts
of the boiler, should be rolled or expanded therein, union or flange joints being
liable to give trouble, especially when exposed to the extreme heat of fires under
forced draught; (c) that the construction should be such as to permit of any
defective tube being readily removed and a new one fitted without injury to or
removal of any other tube; (d) that the furnace or firebox should be such as to
ensure a satisfactory combustion of the fire-gases with ordinary coal and stokers;
(e) that the arrangements for promoting combustion of fuel and circulation of water
should be such as not only to give satisfactory results at slow speeds under natural
draught but also to enable the boiler to be worked without danger under forced
draught as an express boiler, and that, in this connection, the tubes exposed to the
greater heat should be ensured a plentiful supply of water; (f) that the
construction should be such as to obviate rigidity as also undue strains such
as are liable to arise owing to the extreme and rapid changes of temperature and
pressure to which water tube boilers are subjected; (g) that in order to obviate,
as far as possible, the considerable reduction in evaporative efficiency, which is
liable to occur from carbonaceous or other non-conductive deposits on the outer
surfaces of the tubes of boilers of the type referred to, alter they have been under
steam for a relatively short period (especially when burning bituminous coal), there
should be provision for properly cleaning the tube surfaces with facility and
despatch whilst the boiler is under working pressure and the fires are burning;
(h) that, with the view of keeping the internal surfaces of the tubes as free as
possible from deposit, means should be provided for effecting purification of the
water in the boiler in an automatic and continuous manner; and (i) that the water
carried over with the steain from the heating tubes should be discharged into the
steam drum or header above the water line therein.

page_text: Now my invention has reference to an improved construction of sectional
water tube steam generator designed to fulfil the requirements above indicated
and which I shall now describe in detail with the aid of the accompanying
drawings, wherein
Fig. 1 is a vertical longitudinal section of a steam generator constructed according
to this invention.
Fig. 2 is a front elevation thereof partly in section and with the front casing
removed.
Fig. 3 is a front view of the steam drum and sediment chamber, with their
connecting tubes, removed from the remainder of the boiler.
Fig. 4 is a plan of the boiler with the uptake removed...
Figures 5 to 12 inclusive are detail views drawn to larger scales,
Figs. 5 and 5 are respectively a vertical section and a cross section of one of the
vertical headers and some of the attached parts;
Figs. 6 and 64 are respectively a longitudinal section and a front elevation showing
the joint between one of the horizontal headers, and a junction piece on the steam
drum and
Fig. 7 is a plan of the sediment chamber with the vertical tubes secured thereto
in section;
Figs. 8 and 9 are respectively an elevation and a longitudinal section illustrating
a ferrule applied to the lower end of a tube.
Figs. 10 and 11 are respectively a part elevation and a horizontal section of a
baffling arrangement for diverting the fire gases; and
Fig. 12 is a part elevation of a brush for sweeping the heating tubes.
The remaining figures are hereinafter referred to.
The steam generator comprises a feed collector 1 consisting of a horizontal
box-like receptacle, and a steam and water vessel 2 (herein called the steam drum)
which are connected by a number of curved tubes 3 (herein called furnace crown
tubes) that are ensured a plentiful supply of water, and by a number of inter-
changeable sections or elements each of which comprises a vertical or inclined
header 4 adapted to be secured by a cone, flange, spigot, or other suitable joint or
connection to the feed collector 1, a horizontal or inclined header 5, adapted to be
connected in like manner by any suitable joint or connection to the steam drum 2,
and any convenient number of curved tubes 6 which connect the two headers, the
ends of the curved tubes 6 being attached to the headers 4 and 5 in some suitable
way, as for example by being expanded therein. The headers can be of cylindrical,
oval, rectangular, or other suitable cross sention. In the example shown, the
headers 4 are vertical and connected to the feed collector 1 by screwed unions 4",
and the headers 5 are inclined and connected by means of plates 5º, (Figs. 6, 64)
screwed on the tube ends, and studs and nuts, to a steam and water collector 5 that
is secured over a perlorated portion of the steam drum 2, both sets of headers being
of oval form in cross section.
In those sides of the headers opposite to the sides at which the ends of the eurved
tubes enter them, there are provided plugs, screws or doors-screw plugs 7 are shown
in Fig. 5-for the purpose of affording access for examination, cleaning, or removal
of tubes, or for expanding tabe ends. "The headers 4 and 5 may be constructed of
wrought or cast iron, steel, or other suitable material. They are arranged side
by side in close contact thereby forming a front and a crown to the boiler. The
feed collector 1 is also fitted with plugs, screws, or suitable doors-screw plugs 7
are shown to afford access for the purposes of cleaning, examining, and expanding
the lower ends of the furnace crown tubes 3 and for the removal of these tubes.
whose upper ends are expanded into the steam drum 2, and, in the example shown
extend upward above the level of the water in the said drum. Below the steam
drum 2 is a vessel 9 (herein called the sediment chamber), which is connected with
the steam drum 2 by tubes 10, which may be of any convenient number and diameter
arranged side by side with their external surfaces in mutual contact, thereby
forming a wall. The steam drum 2 is also connected with the sediment chamber 9

page_text: in the example shown, by three downcast tubes 11 placed outside the heating space
of the boiler; if desired, however, instead of this preferred arrangement, the
tubes 11 may be omitted, in which case the tubes 10 will be used as downcast tubes
and will then terminate below, instead of above, the water-level 12, as hereinafter
described. The sediment chamber 9 is fitted with suitable baffles 13, 13 for the
purpose of facilitating the separation of the impurities contained in the water.
Pipes 14 are provided connecting the sediment chamber with the feed collector 1,
preferably through a second sediment chamber 9 with baffles 13, the said pipes
being fitted at the sides of the boiler. The steam drum 2 is fitted with a suitable
baffler, or there may be more than one, to separate from the entering steam, water
carried over therewith. The baffler shown comprises a curved plate 15 arranged
opposite the inlets for jets of mixed water and steam from the tubes 3 and 6, and
formed with perforations 15 over which are arranged other curved plates 15" that
are fixed to the plate 15.
For the purpose of forming a furnace crown and diverting the passage of the
fire gases in order to ensure efficient combustion, firebricks or tiles 16 are arranged
over the furnace crown tubes 3 in such a way as to be easily removable and that
their number can be varied according to the rate of combustion required and the
quality of coal used, a door 17 being fitted in the side of the casing 18 to enable
this to be done. The front portion of the boiler casing is in the form of hinged
doors 18 (Fig. 4) by opening which ready access can be gained to the
headers 4.
For the purpose of regulating the quantity of water admitted to the furnace.
crown tubes 3 and the bent tubes 6 of the sections or elements during the process
of circulation in the boiler, there are provided cone ferrules 19 (see Figs. 8
and 9) constructed of slightly larger diameter than the said tubes and sprung into
place, a gap 20 being cut in the lower part of each ferrule to assist in their
being sprung into place and to ensure drainage of water from the tubes when the
boiler is emptied. These ferrules also serve to prevent-reversal of the circulating
current.
For the purpose of diverting the fire gases there is provided a baffling arrange-
ment (see Figs. 1, 10 and 11) comprising a horizontal shaft or spindle 21 to which
a number of V-shaped (Fig. 11) or otherwise conveniently formel vertical
bafflers 22 are attached, the shaft or spindle 21 being so placed in the boiler
(see Fig. 1) that the baffers 22 fit in between the heating tubes 6 of the elements
at the gaps formed between the elements, and a suitable lever or levers (not shown)
being provided on the shaft or spindle 21 so that it can be worked from the outside
and whereby the angle of the bafflers can be adjusted. When the bafflers 22 are
in the vertical position shown, the boiler can be advantageously worked at com-
paratively slow speeds under natural draught, and upon turning them upwards into
a more or less horizontal position, the boiler can be worked without danger under
forced draught as an express boiler.
The heating tubes 6 of the elements can be cleaned by a steam jet in the usual
manuer admitted through the smoke box door 23, but in order that the external
surfaces of the said tubes may be more thoroughly cleaned, bearings 24 (Fig. 1)
are provided in a position eccentric to the axis of the curve of the tubes to be
cleaned; into these bearings the spindle 25 of a compound brush (Fig. 12), some-
what resembling a comb, with bristles 26 on its teeth 27 and which can be kept in
the stokebold, can be shipped upon opening the door 23 so that by means of a
suitable lever or levers (not shown) the brush can be worked in an upward aud
downward direction, thereby sweeping the soot from the surfaces of the tubes.
Feed water is injected into the steam drum 2 and descends the downcast pipes 11
into the sediment chamber 9 where the impurities are deposited, clean water rising
over the bafflers 13" through the tubes 10 into the steam drum 2 and through the
connecting pipes 14 into the feed collector 1, whence a portion of it passes into the
furnace crown tubes 3 and thence into the steam-drum 2 and a portion into
the vertical headers 4 and thence by the curved tubes 6 of the elements and the

page_text: headers 5 into the steam drum. The water is separated from the steam by means
of the bafflers 15 and again descends, together with the feed water, through the
downcast tubes.11 into the sediment chamber 9, and so forth. A blow-off pipe 28
is connected to the sediment chamber 9 for the purpose of blowing out the
sediment or water from the boiler from time to time.
The headers, steam drum, feed collector, and sediment chamber are or may be
suitably connected together by stay rods 29, as indicated by dotted lines in Fig. 1,
to prevent undue straining of the joints between the headers 4, 5 and the feed
collector and steam drum 2 by expansion of the tubes 6 connecting the
benders.
Figs. 13 to 16 inclusive illustrate a modified construction of steam generator
according to this invention, Fig. 13 being a longitudinal vertical section; Fig. 14
a front elevation with the front casing removed; Fig. 15 a rear elevation with the
rear casing removed and parts of the tubes 10 broken away; and Fig. 16 a plan.
partly in horizontal section and with some of the interchangeable sections or
elements removed.
In this construction the feed collector is constructed with two independent
horizontal box-like parts 1, 1 carried by the pipes 14, the furnace erown tubes 3
being secured at their lower ends to the lower part 1 and the vertical headers being
each secured to the upper part 1 conveniently by a bolt 4 screwed and pinned to
bridge piece 4 and provided with a nut 4 by tightening up which the lower
perforated end of the hender will be forced tightly upon a conical union 44 serewed
in the part 1 so as in this way to produce a steam tight joint between the two.
Each of the upper headers 5 has two lugs 5* rivetted to it at one end and is
connected by Theaded bolts 5 to a junction piece 5 so as to form a fluid tight
joint therewith and which is secured over boles 2 in the steam drum 2, the arrange-
ment being such that the headers can be readily fixed in place and removed
independently of each other. Instead of this mode of connectión, each header 5
may be secured to the junction piece 5d by a bolt 5 which is screwed into a bridge
piece 5' within the steam drum, and is provided at its outer end with a nut 5 and
washer. Both modes of connection may be employed together as in the arrange-
ment shown. The baffler 15 is similar to that herein before described but is secured
at both ends with its concave side towards the holes 2 in the steam drum and is
provided with a curved plate 15 above the upper ends of the furnace crown tubes
which are secured to the lower portion of the steam drum. The bottom of the
steam drum is in communication with the sediment chamber 9 by the tubes 10
constituting the rear wall of the combustion chamber, these tubes being preferably
curved outwardly as shown and secured to the bottom of the steam drum. The
sediment chamber 9 is connected to the feed collector 1, 1 by the pipes 14. In
other respects the construction of steam generator shown in Figs. 13 to 16 inclusive
is substantially the same as that hereinbefore described with reference to and
shown in Figs. 1 to 4 inclusive.
Each of the steam generators shown is provided with a suitable grate 30, fire
doors 31, ashpit doors 32, and uptake 33, the bottom of which is arranged between
the adjacent enda of the headers 4 and 5. By the constructions described, a large
amount of tube heating surface can be conveniently fitted into a small space.
Having now particularly described and ascertamed the nature of the said iuven-
tion and in what manner the same is to be performed I declare that what I
claim is :-
1. In a steam generator, a feed collector, a steam drun, interchangeable sections
or elements and furnace crown tubes that are connected to the said feed
collector and to the steam drum, the said interchangeable sections or elements
each comprising two tubular headers connected by a series of curved heating tubes,
substantially as described.
2. A steam generator comprising a horizontal feed collector, a steam drum
curved furnace crown tubes connecting the said feed collector and steam drum.

page_text: interchangeable sections or elements each comprising a vertical or inclined tubular
header connected to the said feed collector, a horizontal or inclined tubular header
connected to the said steam drum, and a number of curved tubes connecting the
two headers, the headers connected to the feed collector being arranged close
together so as to form part of the front of the generator and the headers connected
to the steam drum arranged close together so as to form the crown of the generator,.
and tubes connected to the steam drum and which are located at the opposite side
of the furnace to the feed collector between which and them there is communication
substantially as described.
3. In a steam generator of the kind referred to the hereinabove described
relative arrangement of the uptake, the headers, the curved heating tubes con-
necting the headers, the feed collector, the steam drum, and the furnace, the uptake
baving its lower inlet end for hot gases located between the adjacent ends of the
headers as specified.
4. For regulating the quantity of water admitted to a heating tube of a steam.
generator, a conical ferrule inserted in the lower water inlet end of the said tube
and having a gap in its lower part to ensure drainage of water from the tube when
the boiler is emptied, substantially as hereinbefore described.
5. In a steam generator the combination with an uptake and a number of
elements each including two headers connected by curved tubes, of an adjustable
baffling-arrangement comprising a horizontal shaft carrying bafflers extending down
between the heating tubes of the elements at the gaps formed between the
elements, and capable of being raised and lowered, substantially as herein before
described for the purpose specified.
6. In a steam generator comprising headers and curved water tubes connecting
them as set forth, a compound brush in the form of a comb having bristles on its
teeth, and adapted to turn about an axis in bearings so arranged in the smoke
box or lower part of the uptake that the said brush when turned about the said
axis will be caused to travel in a curved direction eccentric to or different from.
that of the curved portions of tubes and so will have a sweeping effect in directions
not parallel to the axes of the tubes substantially as hereinbefore described for the
purpose specified.
7. My improved steam generators constructed substantially as hereinbefore
described with reference respectively to and shown in Figs. 1 to 4 inclusive and in.
Figs. 13 to 16 inclusive of the drawings annexed.
Dated this 19th day of December 1896.
W. LLOYD WISE,
46 Lincoln's Inn Fields, London, W.C., Chartered Patent Agent..