Year: 1895

page_text: 1, ALFRED BLECHYNDEN, of 276, Abbey Road, Barrow-in-Furness, Engineer,
o hereby declare the nature of this invention to be as follows:-
This invention relates to steam generators and means for heating the feed
water for same, and has for its object increased economy in the working of such
generators.
In some
With this object in view I prefer to make the boiler much smaller than usual
and to use in conjunction therewith a feed water heater which receives its heat
from the gases escaping from the boiler furnaces and so arranged that the pressure
within the heater is maintained lower than the pressure in the boiler.
cases the heater may be part of the structure of the boiler, but arranged so that
the water sides of both are separate and so constructed that a different pressure
may be maintained in each. By preference, however, I make the heater an
entirely separate part, of any convenient form such as cylindrical, with flat ends,
and tubes passing through it in the direction of its axis, through which the
products of combustion pass on their exit from the boiler. Or the heater may be
of the "water-tube" or "tubulous" type with the water inside and the heated
gases outside the tubes; or it may be a combination of both fire tube and water
tube types. In its course from the hotwell or other source of supply to the boiler,
the water is first pumped or forced by suitable means, such as an injector, into the
heater and is pumped from thence into the boiler. This may be accomplished by
various means but by preference I use a special pump of the double acting
description, with the suction and delivery valves and pipes so arranged that the
end of the barrel through which the pump rod works supplies the feed heater with
water, which after being heated and consequently occupying a larger volume-
flows from the heater into the other end of the pump barrel, from whence it is
discharged into the boiler. A suitable relief valve is fitted to the water side of
the heater, or to the line of pipes connecting the two ends of the pump, so as to
prevent the pressure in the heater being increased higher than that desired, by
reason of the water having-after being heated-a greater volume than the end
of the pump having the larger capacity will accommodate. In other cases I use
two pumps of suitable capacities, one of which feeds the heater and the other feeds
the boiler, worked simultaneously; and in other cases I make one or both of the
pumps so that the stroke can be regulated by means of the movement of a piu in a
slot in the lever or crank by which the piston or plunger is worked, or by other
suitable means, the object being to make the relation of the capacity of the first to
that of the second pump approximately equal to the relation of the volume of the
water before to the volume of water after heating.
There are cases where it is desirable to make the heater with a free water-level
and an air or steam space, in which cases I prefer, though it is not absolutely
necessary, to supply the heater and boiler by means of two separate and independent
pumps, preferably worked by steam, each having its discharge controlled by a
regulator operated by the changes of water level in the vessel which the pump
supplies. These regulators may be of any suitable type, such, for example, as a
balanced float-worked lever made to operate a cock, shut off valve, or regulator

page_text: valve, on the feed outlet, similar to that commonly adopted in household water
supply cisterns. On the steam supply valves of the pumps may be operated by
means of floats attached to levers and rods or by other suitable mechanism, so that
when the level of the water rises the steam supply valve is closed and when it falls
the steam supply valve is opened.
In other cases I prefer to use an injector or inspirator of any type to force the
water from the hotwell or supply tank into the heater, a float being fitted in
the heater, which controls the injector steam supply, through levers or other
convenient mechanism, so that when the water level falls the steam supply is
opened and when it rises the steam supply is closed. Or the outlet into the heater
may be fitted with a feed regulator such as already referred to and may have a
loaded escape valve to permit any surplus water to be returned into the hotwell
or tank.
The steam or air space of the heater may be fitted with a spring or other loaded
valve arranged to discharge into the hotwell, condenser, or other suitable part;
and in some cases I adopt in conjunction therewith a float operated lever actuated
by the changes of water level in the heater, so that when the surface falls lower
than a certain level the lever operates through suitable mechanism and eases the
valve.
The following are some of the combinations of steam generator and feed water
heater which I prefer to use.
66
In a tubulous boiler of the three chambered type such for example as those
described in my Patent Specifications numbered 18311 and 22943 of 1893 and
9517 of 1895 I place a multitubular fire tube" low pressure heater (with its
water supply arranged as described) along each side of the upper chamber by
preference with its tubes vertical or inclined upwards. The course of the gases
from the fire is then between and amongst the groups of generating tubes of the
boiler and thence upwards through the tubes in the heater and to the chimney.
In some cases I place a series of pipes in a line extending from the outside of each
heater towards the outer part of each bottom chamber which leaves a space on
each side of the boiler enclosed by the heater bottom, the group of generating
tubes, the said series of pipes, and the ends of the boiler casing. The tubes of
this series may be arranged horizontally, one over the other, and connected at the
ends in pairs so as to form in effect one pipe bent backwards and forwards; or
they may be connected in groups, or altogether, at each end by headers. In other
cases they may be placed vertically, side by side, and connected as already
described, or at the top to the heater and at the bottom to a collector pipe common
to all the tubes. The water may be supplied to the heuter or taken from it to the
boiler feed pump through the said tubes, or when not as last described they may
be connected up between the boiler feed pump and the boiler.
In other cases I adopt a "tubulous " or "water tube" heater at each side of the
boiler, formed of horizontal or vertical or inclined tubes.
Similar arrangements may be made in the case of a boiler having, in place
of one upper chamber, two chambers, placed side by side, and two bottom
chambers.
In the case of a locomotive or «
Navy" type of boiler I prefer to make the
heater, in effect, a continuation of the boiler, when of the fire tube type, by placing
it in front of the outer tube plate of the boiler, with its tubes leading in the same
direction as those of the boiler. I prefer to place it with a space between its tube
plate and that of the boiler, which space is convenient for repairs, and being
plated or closed in may form a secondary combustion chamber. The smoke box
may be attached to the outer end of the heater. The outer case of the heater
may be made cylindrical like that of the boiler.
To increase the heat absorbing power of the heaters I sometimes fit them with
spiral or fluted tubes, and in the case of fire tube heaters with smooth bore tubes I
prefer to fit the tubes with metallic spirals.
In some cases it is desirable to fit a byepass arrangement whereby the gases

page_text: from the boiler furnace may be diverted from the heater. This may consist of a
side flue or flues fitted with doors or dampers, so that when required the products
of combustion need not necessarily pass through the heater before discharging
into the chimney.
I may fit one heater so as to be common to two or more boilers, or more than
one heater may be fitted to each boiler. The feed water may also be heated at
more than one stage before discharging into the boiler, using heaters at increasing
pressures, in which case there will be a pump between each pair of heaters.
314h dow of Santamber 1895
J. A. COUBROUGH,
Registered Patent Agent,
10 St. George's Crescent, Liverpool, Agent for the Applicant.
I, ALFRED BLECHYNDEN, of 276, Abbey Road, Barrow-in-Furness, Engineer,
do hereby declare the nature of the said invention and in what manner the same is
to be performed to be particularly described and ascertained in and by the
following statement :--
This invention relates to steam generators and means for heating the feed
water thereof, and has for its object increased economy in the working of such
generators.
With this object in view I divide the steam generator into two or more parts, in
which the water to be evaporated is heated at as many different stages and different
pressures, and I cause the furnace gases to act upon the different parts of the
generator in the order of decreasing pressures, that is to say, the gases when
evolved from the burning fuel come first in contact with that part of the generator
from which steam of the required pressure is withdrawn for use, and subsequently,
as their temperature diminishes, with the part next lower in pressure, and so on.
I thus apply in practice the discovery-which has evolved from a lengthened
series of experiments which I have made-that the rate at which heat is trans-
mitted through a plate and absorbed by water depends much ou the pressure under
which the water is, lower pressure being more favourable to the operation than
higher pressure. The application of this discovery has also the advantage that
only one part of the generator need be made of a strength necessary to withstand
the working pressure of the stean, which is very important with very high
pressures.
In carrying out this invention I so conduct feed water to the said steam
generator that it passes from the source of supply into that part of the generator
which is worked at the lowest pressure, passing from thence into the next part in
order of increased pressure, arriving finally in the steam generator proper, which
is worked at the highest pressure. In practice however it is not anticipated that
the generator will be divided into more than two portions, one of which will be
used as the feed heater, and the other as the steam generator proper.
For this purpose of feeding water from one portion to another of the steam
generator, employ suitable apparatus, such as pumps, injectors, or inspirators; .
and in order to regulate or relieve pressure in the low pressure portion or portions
I employ suitable pressure relief devices.
In putting this invention into practice it will be evident that many different
forms or constructions of steam generators may be employed, and that the
auxiliary appliances or adjuncts of said generators-of which the application of

page_text: this invention entails the use-will be correspondingly varied in construction and
disposition, some of which are hereinafter more particularly described.
STEAM GENERATORS.
In the case of a locomotive or 66
Navy" type of boiler, I prefer to make the
feed heater in effect a continuation of the boiler, when of the fire tube type, by
placing it in front of the outer tube plate of the boiler, with its tubes leading in
the same direction as those of the boiler. I prefer to provide a space between the
tube plates of the boiler and feed heater, which space is convenient for repairs
and being plated or closed in forms a secondary combustion chamber. The outer
case of the feed heater is preferably cylindrical, like that of the boiler. The
smoke box may be attached to the outer end of the feed heater.
In a tubulous boiler of the three-chambered type, such for example as those
described in my Patent Specifications numbered 183113, 229439, and 9517",
I place a multitubular "fire-tube" low pressure feed heater along each side of
the upper chamber, by preference with its tubes vertical or inclined upwards.
The course of the gases from the fire is thus between and amongst the groups of
generating tubes of the boiler and thence upwards through the tubes in the feed
heater, and so to the chimney. In some cases I arrange a series of pipes in a
plane extending from the outside of each heater to the outer part of each bottom
chamber. The tubes of this series may be arranged horizontally, one over the
other, and connected at their ends in pairs so as to form in effect one pipe bent
backwards and forwards; or they may be connected in groups, or altogether, at
each end, by headers. In other cases they may be placed vertically, side by side,
and connected as already described, or at the top to the heater and at the bottom
to a collector pipe common to all the tubes. The feed water may be conducted to
the heater, or taken from it by the boiler pump, through the said tubes.
In other cases I substitute. tubulous or "water-tube" heaters for the fire-tube
heaters above referred to, which I arrange on each side of the upper chamber of
a three-chambered type of boiler as above described.
Similar arrangements may be made in the case of a boiler having in place of
one upper chamber, two chambers, placed side by side, and two bottom chambers.
STEAM GENERATOR ADJUNCTS.
Feed water may be permitted to flow from a pressure main, or by gravity from
a tank, into the feed heater or low pressure portion of the steam generator, or
where it is available the air pump of a condensing engine may be used for this
purpose. From the feed heater the water may be forced into the steam generator
by ordinary feed pumps; but I prefer to employ a special form of pump or
pumps for the purpose of supplying the heater with water and feeding it to the
steam generator, different forms and arrangements of which will now be described.
In some cases I use a pump of the double acting description, with its ports and
water connections so arranged that the end of the barrel through which the pump
rod passes supplies the feed heater with water, which, after being heated and
consequently occupying a larger area flows from the heater to the other end of the
pump barrel, from whence it is discharged into the steam generator.
In other cases 1 use two pumps of different capacities, the smaller of which
feeds the heater, and the larger of which feeds the steam generator, and which
may work synchronously; or 1 make one or both of the pumps so that the stroke
can be regulated by means of a pin in a slot in the crank or lever by which the
pump piston or plunger is worked, or by other suitable means, the object being to
make the relation of the capacity of the first to that of the second pump approxi-
mately equal to the relation of the water before and after being heated.
There are cases where it is desirable to make the heater with a free water level
and an air or steam space, in which cases I prefer, though it is not absolutely

page_text: necessary, to supply the heater and the steam generator by separate and indepen-
dent pumps, preferably worked by steam, each having its discharge controlled by
a regulator operated by the changes of the water level in the vessel which the pump
supplies. These regulators may be of any suitable type, such for example as one
of the forms described in the Complete Specification of my Application for
Patent No. 11253, or may consist of a balanced float-worked lever made to
operate a cock, shut-off valve, or regulator valve, on the feed inlet, similar to that
commonly adopted in household water supply cisterns. Or the steam supply valves
of the pumps may be controlled by means of floats attached to levers and rods, or
by other suitable mechanism, so that when the level of the water rises, the steam
supply valve is closed, and when it falls the steam supply valve is opened.
In other cases I prefer to use an injector or inspirator of any suitable type to
force the water from the hot-well or supply tank into the heater, a float being
fitted in the heater which controls the injector steam supply, or steam and water
supply, through levers or other convenient mechanism, so that when the water
level falls the steam supply valve is opened, and when it rises the steam supply
valve is closed; or the inlet into the heater may be fitted with a feed regulator
such as already referred to, and may have a loaded escape valve on its pipe to
permit any surplus water to be returned into the hot-well or tank.
I fit the heater, or the pipes or pump chamber in communication therewith,
with a suitable escape valve to prevent the pressure in the same exceeding a
predetermined limit; and where such a valve is fitted to a heater having a free
water level and an air or steam space, I may adopt in conjunction therewith a
float operated lever actuated by the changes of water level in the heater, so that
when the water level falls lower than a certain limit the lever operates through
suitable mechanism and eases the valve.
DESCRIPTION OF THE DRAWINGS.
Figure is a sectional elevation, and Figure 2 a cross section, illustrating a
compound boiler according to this invention.
A denotes the high pressure or steam generating portion of the boiler, provided
with the combustion chamber A¹ and fire tubes a. In front of the outer tube plate
of the portion A is disposed the low pressure or feed heating portion B of the
boiler, provided with fire tubes b. A space C thus exists between the high and
low pressure portions of the boiler, which being plated in forms a secondary
combustion chamber, the course of the furnace gases being, from the combustion
chamber A¹ through the tubes a, chamber C, tubes b, to the chimney D. E, F are
two feed pumps, working independently. The pump E draws water from the
source of supply through the inlet e, and injects it through the pipe el into the low
pressure portion B. The pump F withdraws water from the portion B through
the pipe f, and injects it through the pipe f¹ into the high pressure portion A of
the boiler. In order to regulate the inflow of feed water to the portion B,
I provide the inlet pipe el with a valve e' which is controlled by a float within
the portion B. The valve e may be an adaptation of the ordinary cistern ball
cock, with a stop valve. The inflow of feed water to the portion A is regulated
by a valve f which is controlled by a float f³ within the said portion. The
valve fis by preference one of those described in my Complete Specification
No. 11253. An escape valve b¹ allows the escape of any air or steam which
might otherwise accumulate within the portion B, and in conjunction with the
valve there may be employed a float operated lever 6' whose function is to ease
the valve as the water level in B falls.
Figure 3 is a sectional elevation and Figure 4 a cross section of a compound
boiler constructed similarly to that above described, but worked with one pump, G,
the construction of which will be understood upon reference to Figure 5 (sectional
elevation) and Figure 6 (cross section on line A. B). G is the pump barrel,
Hits plunger, and J its steam cylinder. A downward stroke of the plunger H

page_text: draws water from the source through the inlet g into that end of the barrel
through which passes the pump rod . The next upstroke forces this volume of
water through the outlet gl and pipe e to the portion B. The same upstroke
draws heated water from the portion B through the inlet 9 and pipe f, and the
succeeding downstroke expels it through the outlet and pipe to the high
pressure portion A. I thus employ the end of the pump barrel having the
smaller capacity, i.e. that in which the pump rod works, for dealing with the feed
water before it is heated, and the end of the pump having the larger capacity for
dealing with the same water after it is heated and expanded. 9' is a loaded escape
valve on the outlet g¹ of the pump G, which discharges into the suction g, the
function of this valve being to prevent the pressure of the pump discharge
exceeding a predetermined limit. In place of adapting the float lever 6' to ease
the escape valve 61 (as in Figure 2) I may arrange it (as in Figure 4) to control a
valve discharging into the outlet of the valve b', and whose function is--when
the water level in B falls- to provide an exit for air or vapour.
Instead of using a double acting pump having different capacities at each end,
for the purpose of dealing with water before and after it is heated and expanded,
I may employ the special form of pump illustrated in Figure 7. This pump has
two barrels, K and L. The plunger k of the barrel K is carried by the pump
rod h and has a constant stroke, whilst the plunger 1 of the barrel L is actuated
by the lever M coupled to the pump rod h. In order to vary the stroke of the
plunger 1, the head of its connecting rod is adjusted towards or away from the
fulcrum of the lever M by means of the screwed pin m. I prefer to employ
the pump K to draw heated water from the portion B and force it into A, and to
use the pump L for pumping water from the source into the portion B; therefore
in order to allow for the expansion of water in the portion B it is necessary that
the delivery of the pump L which feeds it should be less than the suction of the
pump K which withdraws from it, and I accomplish this by shortening the stroke
of the plunger by adjusting its connecting rod head nearer to the fulcrum of the
lever M. g is the inlet from source, g₁ the outlet to portion B, 9 inlet from
portion B, and 9 the outlet to portion A. I may however use the pump K for
feeding the portion B, and the pump L for feeding the portion A, and in this case
the stroke of the plunger must be lengthened by adjusting its connecting rod
head away from the fulcrum of the lever M.
Figure 8 is a sectional elevation of a compound boiler according to this inven
tion, worked by separate pumps E, F, whose action is directly controlled by floats
on the surface of the water in the respective portions of the boiler which they feed.
The steam admission valve of the pump E is controlled by the float es, lever e
and rode, whilst the steam admission valve f of the pump F is controlled by the
float f, lever fo and rod f7, the function of the said floats and levers being to
admit steam to their respective pumps when the water level falls in the portions
which they feed, and to cut-off steam when said level is normal.
Figure 9 (sectional end view) and Figure 10 (sectional side view) shew a water
tube boiler of the three-chambered type adapted to this invention. The low
pressure portion of this boiler comprises two nests of water tubes B, disposed one
on each side of the upper high-pressure chamber A, and a wall of water tubes B¹
arranged in a plane extending from the outer tubes of the nests B to the outer side
of each high pressure lower chamber A. The tubes B and B are arranged
horizontally and are connected at their ends in pairs by headers B³, forming in
effect one tube bent backwards and forwards. The course of the gases from the
fire is thus between and amongst the generating tubes of the portion A and
thence upward and past the tubes B' and B, to the chimney D. The high and
low pressure portions A and B are supplied with feed water by the pump G,
whose connections and functions have already been described with reference to
Figures 3 and 4; and it will be noted that feed water from the source enters the
walls of tubes B₁ primarily, and passes from thence to the nests of tubes B.
A loaded escape valve B* upon the heated water outlet from the nests of tubes B

page_text: allows the escape or surplus water, and the discharge from his valve may be ret
to the hotwell or other place.
In the boiler shewn in Figure 11 (sectional end view) and Figure 12 (sectional
side view) chambers B provided with fire tubes 6 are substituted for the nests of
tubes B in Figures 9 and 10. In other respects this boiler is identical with that.
described with reference to Figures 9 and 10.
Having now particularly described and ascertained the nature of this inven-
tion and in what manner the same is to be performed, 1 declare that what I
claim is :-
1. For the purpose of more economically transferring heat to water being fed
to a steam generator, heating the said water at a pressure lower than that of the
steam generator by the gases escaping from the furnace of said steam generator,.
substantially as herein described.
2. For the purpose of more economically transferring heat to water being fed
to a steam generator, heating the said water in stages at gradually increasing
pressures (but lower than that of the said steam generator) by the gases escaping
from the furnace of said steam generator, substantially as herein described.
3. For the purpose of more economically transferring heat to the water supplied
to a steam generator, sub-dividing such generator into two or more portions, said
portions being under as many different pressures, and causing said portions to be
heated seriatim in order of decreasing pressures by the furnace gases of said
generator in their passage from the fire to the chimney, substantially as herein
described.
4. The arrangements and combinations of a steam generator and a feed water.
heater illustrated in the drawings annexed and described, wherein such feed water
heater is maintained at a lower pressure than the steam generator and is heated by
the gases escaping from the furnace of said steam generator, and a pump or its
equivalent so arranged that it draws water from the heater and discharges it into.
the steam generator, substantially as and for the purposes herein set forth.
5. In combination with a compound boiler such as herein described, a double
acting barrel pump the capacities of whose opposite ends are approximately
proportional to the volumes of water before and after it is heated in the low
pressure portion of said compound boiler, the end of the pump having the
smaller capacity being arranged to draw from the source of supply and to.
discharge to said low pressure portion, and the end having the larger capacity
being arranged to draw from the low pressure portion and to discharge to the high
pressure or steam generating portion of said compound boiler, substantially as.
and for the purposes herein set forth with reference to Figures 5 and 6 of the
drawings.
6. In combination with a steam generator and a feed water heater worked
at a pressure lower than that of the steam generator and deriving its heat
from the gases escaping from the furnace of said generator, one or more pairs.
of pumps or their equivalent, the capacities of individual pumps of the pair, or
each pair, of pumps being proportional to the volume of a body of water before
and after it is heated, the smaller of said pumps being arranged to supply water
from the feed source to the feed heater, and the larger of said pumps being
arranged to feed water from the heater to the steam generator, substantially as.
herein set forth.
7. In combination with a steam generator and a feed water heater worked at a
pressure lower than that of the steam generator and deriving its heat from the
gases escaping from the furnace of said generator, a pair or pairs of pumps.
arranged to feed such feed heater and steam generator alteruately, the stroke of
the individual pumps supplying the feed heater and steam generator, respectively,.
being capable of adjustment relatively to the volume of a body of water before
and after being heated, substantially as herein set forth with reference to
Figure 7 of the drawings.

page_text: 8. In combination with a steam generator and a feed water heater worked at
a pressure lower than that of the steam generator and deriving its heat from the
gases escaping from the furnace of said generator, the employment of independent
pumps or their equivalent, for feeding such feed heater and steam generator, the
discharge outlets or steam valves of which are controlled by devices operated by
the water level in said feed heater and steam generator, substantially as herein set
forth with reference to Figures 1, 2 and 8 of the drawings.
9. In combination with a steam generator, feed heater, and pumps, arranged
and operating as herein described, an escape or safety valve on such feed heater,
or on the pipes or part of the pump chamber in communication therewith, for
the purpose of preventing the pressure in such feed heater from exceeding a
predetermined limit.
10. In combination with a steam generator, feed heater, and pumps, arranged
and operating as herein described, an escape or safety valve on such feed heater,
which by means of float operated mechanism actuated by the water level in said
heater, is eased for the escape of accumulated air or steam when said water
level falls, substantially as set forth with reference to Figures 1 and 2 of the
drawings.
Dated this 15th day of July 1896.
J. A. COUBROUGH,
Registered Patent Agent (Qual. by Exam.),
10 St. George's Crescent, Liverpool, Agent for the Applicant.