Improvements in and connected with Steam Generators and their Furnaces.
Year: 1896

page_text: .Date of Application, 21st Mar., 1896-Accepted, 23rd May, 1896
COMPLETE SPECIFICATION.
Improvements in and connected with Steam Generators and their
Furnaces.
I, HENRY MATHESON, of 1 Castlenau Cottages, Barnes in the County of
Surrey, Gentleman 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:-.
My invention has for its object to provide steam generators, which are simple in
construction, efficient and economical in working, as nearly as possible automatic
in action, and easily maintained in order and all their parts readily accessible for
repairs or examination.
According to my invention the generating tubes are preferably straight and are
each provided in the interior with a mid-feather or longitudinal diaphragmn whereby
tubes of comparatively small diameter possess the advantages of large tubes with
the additional advantages of small tubes. The number diameter and length of the
tubes will of course depend on the size and requirements of the boiler. The said
tubes are arranged horizontally or approximately 50 in vertical rows or tiers one
end of each tube being closed and provided with a slightly tapered projection to
form a support for that end of the tube when in position. The opposite or front
end of each tube is splayed out or slightly tapered for a suitable distance for
a purpose to be hereinafter described.
The tubes comprising each vertical row or tier are connected with each other by
a vertical hollow column or tube which communicates at its upper end with
a horizontal tube constituting a steam dome whilst the lower end of the said
vertical column communicates with another horizontal tube or passage which latter
communicates with two other vertical tubes or passages into which the feed water
is fed. These two last mentioned vertical tubes are connected at their upper ends
to the steam dome. The lowest tube of the said rows or tiers receives water from
the vertical tubes into which the water is fed and the uppermost tubes of each
tier discharge steam and water into the steam dome from which the small quantity
of water carried thereinto by the steam will flow back into the vertical water tubes
and thence into the generator tubes.
Each generator tube may be provided with a safety cap stopper or valve Bo
arranged that in case of a tube being ruptured an excess of pressure will act on
the back of the said valve or cap of the ruptured tube and cause the said cap to
move into position to stop the flow of water and steam through the said tube.
I provide in connection with the boiler a simple and reliable automatic water
feeding device consisting of a strong upright cylindrical vessel securely closed at
both ends. The water enters this vessel through a pipe extending up through the
bottom of the vessel. The circumference near the top of this pipe inside the vessel
is slotted or perforated with rows of small holes and above this pipe and in a line
therewith is a float from the top of which projects a slender but strong pin by
which the float is guided in its movements. The bottom part of this float is
furnished with a collar which fits accurately but loosely round the outside of the
water supply pipe. When the level of the water in the boiler sinks, the float with
its collar also sinks, thus uncovering the holes in the feed pipe and allowing the
feed water to run freely in, the reverse of this taking place when the water level
rises too high.

page_text: The bolts, nuts and flanges intended of themselves to form steam and water tight
joints liave a knife edge or bend, which when screwed up tight against a thin
washer of soft copper or other suitable material makes a convenient and sound
joint.
To prevent the nuts and bolts from getting loose a slot is made either on the
outside of the bolt or in the inside of the nut and when the nut or bolt has been
screwed up sufficiently tight it is locked by inserting a triangular pin of hardened
steel in the slot.
Inserted in each end of the boiler furnace is an air nozzle set at such an angle
that their respective currents of air meet in the centre of the furnace above the
fuel. To allow room for this, two sets of furnace bars are arranged to slope
towards the centre of the furnace. The sides and ends of the furnace and also any
part of the boiler or easing requiring protection from the flame, and heated gases,
may be protected by plates of iron of convenient size and shape the said plates
being provided with a facing of fire clay or other suitable non heat conducting
substance secured and kept in place by flat headed studs rivetted in the plates
and caused to project from the plates a short distance into the said fireclay or
the like. The furnace is isolated from the outside casing of the boiler by an air
space.
In order that my invention may be clearly understood I will further describe
the 'same with reference to the accompanying drawings premising however that
I do not restrict myself to the precise details of construction illustrated and
described.
Figure 1 represents part in front elevation and part in transverse section a water
tube boiler constructed according to my invention and Figure 2 is a longitudinal
section of the same.
Figure 3 shews in longitudinal section (drawn to a larger scale) portions of two
of the generator tubes and a vertical hollow column (or tube) with which they are
connected.
Fig. 4 represents partly in elevation and partly in section one of the vertical
hollow columns or tubes with one of the horizontal tubes in section and also the
closed front end of another of the said tubes in elevation.
Figures 4 and 4" shew the means of connecting the vertical columns to the
steam collector or dome.
Figure 5 shews in vertical section my improved water feeding device and
Figure 6 is a horizontal section of a part of the same.
Figures 7 and 8 represent in front elevation and transverse section respectively
a compound slab or block for protecting the walls of the furnace.
Figure 9 is a front view of an improved lock nut and
Figures 10 and 11 are views at right angles to each other of a scraper for
cleaning the exterior surfaces of the tubes.
Referring to Figures 1 and 2 it will be seen that the furnace or fire place A and the
whole of the generator tubes of the boiler are enclosed in an outer casing B inside
which the heated products of combustion from the furnace are caused to circulate
among and impinge upon the exterior surfaces of the tubes on their way to the
uptake or chimney C, which is situated at about the centre of the top of the
casing B. The generator tubes D, are arranged in vertical tiers the front ends of
the tubes of each vertical tier being supported by, and in communication with the
interior of, a vertical column or tube E, whilst the rear ends of the said tubes are
provided with slightly tapered projections F by which the said rear ends are
supported in plates G. The upper end of each vertical column or tube E
communicates with a horizontal tube or chamber I constituting a steam dome, the
opposite ends of which are connected to and communicate with two vertical hollow
columns or chambers K, into which the feed water is fed by automatic water
feeding devices L. as hereinafter described. The columns or tubes E communicate
at their lower ends by pipes M with the interior of a horizontal tube or chamber N
which in its turn communicates at both ends by pipes N2 with the lower parts of

page_text: the vertical columns K. The vertical columns E are connected to the horizontal
tube or chamber I as shewn in Figures 4 and 48 by bolts and nuts a and in order
to make a steam tight joint between the parts there is formed on the face of one of
the parts a recess & containing a washer of copper or other suitable soft metal c
with which a knife edge or V shaped projection d on the other part is caused to
bear. The horizontal tube or chamber I is provided with a lip or projection e on
which rests the right angled portion E' of the vertical tubes or columns E, the
said chamber I thereby serving to partially support the weight of the said vertical
columns. The generator tubes D. are each provided in the interior with a mid-
feather or longitudinal partition D¹ as shewn in Fig. 3 which may be formed in
one with the tube or it may consist of a thin metal plate inserted therein. This
mid-feather or partition plate extends the entire length of the tube except at the
rear end, a space equal to about 3rds of the internal diameter of the tube being left
between the end of the partition and the inner end of the tube for the passage of
water and steam from one side of the partition to the other side. The front end of
each tube D is for a short distance longitudinally slightly tapered to fit similarly.
tapered openings E' in the vertical tubes or columns E. In each tube D, on opposite
of the partition or mid-feather D' openings f are provided corresponding to the
bore or passage g in the column E. The front end of the tube is closed by a screw
plug or cap O, provided with an annular knife edge or V shaped projection
bearing on a soft metal washer i so that when the plug or cap is screwed home in
the end of the tube a perfect steam and water tight joint is ensured. The tubes.
are inserted through the openings E in the vertical columns E the projections on
the rear ends of the tubes entering holes in the supporting plates G. When the
tubes are in place they are each retained in position by means of a set screw k
screwing into a bar or girder the ends of which engage with lugs or undercut
projections m provided on the columns E. The set screw k also prevents the plug:
or cap O from unscrewing or getting loose. The lower ends of the columns K
may be provided with a blow-off cock for discharging sediment which may collect
therein. In each generator tube D there may be provided a safety device by
which in case of a tube being ruptured the said fube will be closed or isolated from
the other tubes and will not interfere with the action of the boiler. This safety
device as shewn in Figure 3 consists of a short hollow cylindrical valve or
stopper P fitting loosely the tapered end of the tube D. One end of this
cylindrical valve or stopper is closed and in its cylindrical part are two openings p
corresponding in position to the passages g in the columus E. When these safety
devices are provided the mid-feather or partition D' does not extend to the front
end of the tube and instead thereof plates D' are connected to the valve or
stopper P which plates engage at their free ends the partition D' so as to constitute
a continuation of the said partition and behind the said valve or stopper a plate D³
is inserted to prevent the full flow of water or steam at the back of the said valve
or stopper. When the boiler is in normal working order the valve P occupies the
position shewn in the lower part of Fig. 3 and the pressure is equal on both sides
thereof but should the tube be ruptured the pressure on the back of the valve
would be in excess of the pressure in the said tube and consequently the valve
wculd be forced into the position shewn in the upper part of Fig. 3 the passage of
steam and water to the interior of the ruptured tube being thus prevented by the
valve P the said steam and water passing to the next tube above. The damaged
tube can be readily removed by loosening the set screw so that the bar I can be
removed and the tube be withdrawn; the tapered form of the tube and opening in
the column E facilitates its removal. The rear or closed end of the tube may
have the tapered projection F formed in one therewith or the said tapered
projection may be made separately from the tube and be screwed thereto na shewn
in Figure 3, a soft metal washer and a V shaped projection being provided as
shewn to make a steam and water connection between them. The automatic water
feeding device for supplying water to the boiler consists of a strong upright cylindrical
vessel L Figure 5 closed at both ends by steam and water tight covers or closures

page_text: as shewn. Through the bottom or cover R passes a pipe S by which water enters
the vessel. The end of this pipe which is inside the vessel is closed, but in the
cylindrical portion of the pipe which is in the vessel is provided rows of
perforations and fitted to slide on this perforated portion of the said pipe is a
sleeve surmounted by and connected to a float T which is caused to rise and fall
with the level of the water in the vessel L it being steadied in its movements by a
rod U on the top of the said float sliding in guides, provided, in the top of the
vessel.
The rod U is provided with knife edge bearings a which engage the forked
end of an arm fast on a shaft or spindle mounted in bearings in a box or
chamber L attached to or formed in one with the upper part of the vessel L.
One end of the shaft or spindle is formed or provided with a conical head or
bearing surface t seating on a correspondingly coned bearing surface in the
chamber L' whilst the opposite end of the said shaft or spindle is screw threaded
and on this end is screwed a conical bearing piece t seating in a correspondingly
coned bearing surface in the chamber L. By means of these, conical bearing
surfaces the shaft or spindle is free to turn whilst the steam which has access to
the interior of the chamber L is prevented from escaping past the bearings. To
prevent the piece t from turning on the shaft or spindle s and the bearings from
leaving their seats, screws u having pointed ends and carried in a suitable saddle or
bracket, are caused to bear against the head and the piece respectively."
Water enters the vessel L through the perforations g in the supply pipe S and
passes therefrom through a passage W into the vertical column K with which it is
connected and as the level of the water rises in the vessel L the float T rises with
it and causes the sleeve r, to cover more or less the perforations q thereby
regulating the entrance of the water.
When the level of the water in the boiler sinks the valve will also descend and
the sleeve uncover the perforations g and so admit more water to the vessel, the
level of the water in the boiler being thus automatically maintained. The vessel L
communicates with the steam space of the boiler by a pipe or passage W2 near the
upper end of the said vessel. Fast on either the head t of the shaft or spindle st
or on the piece is a pointer X which by the movement of the float T indicates
on a scale the level of the water in the vessel L. and consequently in the boiler.
The furnace or fire place A of the boiler is isolated from the outer casing B by an
inner casing B' between which and the said outer casing is a spacé Y for air. Air
is admitted to the furnace above the fuel through nozzles arranged at an angle in
the ends of the furnace so as to direct the air currents into the space above the fuel
at about the centre of the furnace. To admit of this two sets of fire bars A' are
arranged to slope from the front and back ends of the furnace respectively towards
the centre of the length of the furnace as shewn in Figure 2. The metal side and
end walls of the furnace are protected from the fumes and heated gases by
compound blocks A³ of metal and fire clay or other non heat conducting material.
One of these compound blocks is shewn in Figures 7 and 8 in which it will be seen
that flat headed studs a' are secured to the metal plates As the flat headed ends of
the studs projecting some distance from one side of the said plate on to which the
fire clay or like material a' is moulded the projecting studs being embedded in the
said fire clay or the like so as to securely retain it in position on the said metal
plate.
Portions of the boiler against which the flames from the furnace act may be
similarly protected by compound blocks suitably shaped to fit the said parts. The
furnace door Z is arranged to turn on a horizontal hinge and is counterbalanced
by a weighted lever and bar so as to normally maintain the door in its closed
inclined position shewn in Figure 2. This door opens inwards and when fully open
for charging the furnace with fuel or for cleaning out the furnace assumes a
horizontal position.
The ash pit door is always kept closed except when removing the ashes therefrom
all the air for supporting combustion being admitted to the ash pit and nozzles

page_text: through openings at the sides of the fire door the inclined position of the door
serving to conduct the air in the required direction. In case of explosion or
abnormal pressure from any cause being produced in the furnace the door Z is
prevented from being forced open in an outward direction by the upper end of the
said door coming against a depending portion of the outer casing B. To keep
the outer surfaces of the tubes D free from soot and deposit I arrange to slide
between the several vertical tiers of tubes, scrapers to Figures 10 and 11 formed on
opposite edges with circular notches or recesses corresponding to the outer curve
of the tubes these scrapers being connected to rods wo³ of sufficient length to extend
from the front to the rear ends of the tubes. These rods project through passages
made for them between the vertical columns E their projecting ends being provided
with means for connecting thereto handles by which the said rods and the scrapers
can be slidden to and fro along the tubes and so remove the soot from the surfaces
of the tubes which soot falls into the furnace below.
The bolts and nuts employed for connecting parts of the boiler together are
provided with means for preventing them from loosening as shewn for instance in
Figure 9. The nut Q is provided in the bore or screwed portion with a rectangular
recess or slot Q2 into which when the nut has been screwed up to the desired extent
is inserted a triangular pin or bar g of hard steel which will lock the nut and
prevent it from turning on the screw. To unlock the nut a similar triangular pin
or bar is inserted in the vacant space in the recess or slot Q and the nut can then
be turned in either direction required. Before lighting the fire in the furnace A
water should be run into the boiler until the level of the water reaches about the
fourth row of tubes from the bottom then in a very short time after the fire is
lighted steam will be generated which will force the water up the columns K to a
sufficient height to start the circulation of the water. The water admitted to the
vertical columns K passes by the pipes N' into the horizontal pipe or chamber N
and thence by the pipes M into the lowest tube of each of the vertical tiers of
tubes D beneath the partitions or mid feathers D' therein, round the inner ends of
which partitions it passes on to the upper side thereof and flows there along to the
front ends of the tubes. It then passes upwards through passages g in the vertical
columus E into and below the mid-feathers or partitions in the next row of tubes
above and so on until the level of the water reaches the desired height. Steam
rapidly generates in the tubes and passes into the horizontal chamber or steam
dome 1 from which it may be conducted for use as required. Any water that may
be carried by the steam into the chamber I will flow therefrom into the vertical
columns K.
Having now particularly, described and ascertained the nature of my inven-
tion and in what manner the same is to be performed, I declare that what I
claim is :-
1. In water tube steam boilers, superposed tubes arranged in tiers, each tube in
a tier communicating at one end with a vertical hollow column or tube receiving
water at its lower part and connected at its upper end with a steam collector or
dome, and each tube having in the interior a longitudinal mid-feather or partition
dividing each tube into two passages and causing water and steam to traverse
in a zigzag or circuitous course through the tubes substantially as hereiubefore
described.
2. Steam boilers having superposed tubes arranged in tiers the rear end of each
tube being closed and provided with a tapered projection by which the said rear
end is supported in suitable bearings the front end of each tube being slightly
tapered or conical and supported in a correspondingly tapered or conical hole in a
vertical hollow column or tube connected to a steam collector or dome each tube.
having near the front end two transverse passages communicating with the interior
of the vertical hollow column or tube, one of the said passages being below and
the other above a longitudinal mid-feather or partition in the tube, the said mid-
feather or partition extending from the front end to within a short distance of the

page_text: rear closed end of the tube, whereby water and steam is caused to traverse through
the several tubes in a circuitous direction, substantially as hereinbefore described.
3. Steam boilers having horizontal tubes each provided at its rear end with a
tapered projection by which the said end is supported in a perforated plate or
perforated plates the front end of each tube being slightly tapered or conical and
supported in correspondingly tapered or conical openings in a vertical support or
hollow columnn and the front end being closed by a removable plug or cap the joint
between the tube and the plug or cap being rendered steam and water tight by an
interposed washer of copper or other soft metal with which a V shaped or knife
edge projection on one of the parts is caused to bear, substantially as hereinbefore
.described.
4. The combination with the subject matter of the last preceding claiming clause,
- of means for retaining the tubes in their supports and for preventing the caps or
plugs from being displaced substantially as herein before described with reference
more particularly to Figs. 3 and 4 of the accompanying drawings.
5. Steam boilers having horizontal tubes through which water and steam circulate,
reach tube being provided in the interior with a valve or stopper which in case of
the tube being ruptured, is moved by excess of pressure on one side into position
to prevent the circulation of steam and water through the said tube, substantially
as hereinbefore described.
6. In connection with steam boilers an automatic water feeding device consisting
of a closed vessel communicating with the interior of the boiler, into which vessel
water is admitted by a pipe having perforations (or equivalent inlet) over which is
fitted to slide a sleeve connected to a float so that as the level of the water in the
vessels rises the said sleeve covers more or less of the perforations or inlet and
thereby restricts the entrance for water and as the level of water sinks in the vessel
the float and sleeve descend and uncover more or less of the perforations or inlet
to admit more water substantially as herein before described.
7. The combination with the last preceding claim of an indicator operated by
the raising and lowering motions of the float for indicating the level of the water
in the boiler, substantially as herein before described.
.8. The combination with the tubes of water tube steam boilers of scrupers
capable of being slidden between and along the tubes for cleaning the outer surfaces
of the said tubes from soot and deposit, substantially as hereinbefore described.
9. The combination and arrangement of parts constituting the water tube steam
-boiler hereinbefore described and illustrated by the accompanying drawings.
Dated this 21st day of March 1896.
JOHNSONS & WILLCOX,
47 Lincoln's Inn Fields, London, W.C., Agents.