Improvements in and relating to Steam Motors and Apparatus in connection therewith.
Year: 1899

page_text: Date of Application, 24th Mar., 1899
Complete Specification Left, 24th Jan., 1900-Accepted, 24th Feb., 1900
PROVISIONAL SPECIFICATION.
Improvements in and relating to Steam Motors and Apparatus in
connection therewith.
JAMES MURRIE, 264, St. Vincent Street, Glasgow, North Britain, Engineer,
do hereby declare the nature of this invention to be as follows:-
-
It mainly relates to improvements in steam engines of the multiple expansion
type wherein the steam expands in two or more cylinders on its way to the
atmosphere or condenser and the invention essentially consists in drying the
steam on its passage between each cylinder preferably by means of intermediate
tubular heaters or dryers, the heating agent being steam taken direct from the
boilers or from an independent steam generator working at a higher pressure
than that of the main steam boiler which is utilized in actuating the engine or
engines, the effect of doing so being to prevent water entering the cylinders,
the steam condensing inside the cylinders and by employing a water heater
situated intermediate to the low pressure cylinder and the condenser to absorb
the superadded heat in the steam and thereby effect a considerable saving in
fuel. Said invention is also applicable to engines of the turbine types, the
dryers or heaters being placed intermediate to the turbines in like manner.
In applying my aforesaid invention in practice, say to the present type of
marine engine known as the triple expansion engine, I first construct a steam
generator to work at a comparatively high pressure preferably at from one to
two tons per square inch. This high pressure steam generator is preferably of
the water tube boiler type wherein water circulates inside hollow tubes, the
tubes being enveloped by the furnace gases, or, it may be of the locomotive or
other analogous type of high pressure boiler.
Said high pressure steam generator is provided with a series of inlet and
outlet connections in pairs, each pair consisting of an outlet and return pipes
which are in communication with a separate vessel which I term a steam dryer.
Said steam dryer consists of a miniature form of water tube steam generator
or nest of parallel hollow tubes secured at their ends to chambers in an analogous
manner to the fixing of the water tubes in the generator, only in this case the
steam from the high pressure boiler enters the highest line of tubes preferably
at the highest part and the condensed steam descending ultimately gravitates
back to the high pressure boiler by the return tube or tubes.
Each steam dryer is encased in a steam tight chamber or cylinder made to
withstand the pressure of the steam employed to propel the engine, and the
steam on its way to each cylinder passes through said drying chamber and in
doing so impinges against the tubes and either has its temperature increased or
any surplus water or condensed steam re-converted into vapour. The steam
preferably entering at the lowest end or end containing the condensed steam
leading to the high pressure generator and leaving at the hottest point or part
of the dryer where the live steam enters the dryer.
I do not confine myself to the said type of dryer and may instead jacket the

page_text: high pressure pipe with an outer pipe, passing the steam to be dried inside or
outside the central pipe, the high pressure steam being either in the annular
space or central pipe, or, the dryer may consist of a series of coils or tubes bent
in a gridiron form, the higher pressure steam circulating through these coils
or pipes which are enveloped by the steam to be dried on its way to the engines.
One of the aforesaid dryers is fitted on the main steam pipe connecting the
steam generators with the engines and forming a distance piece thereon, or
the dryer may be directly connected to the first or high pressure cylinder, in
which case the diyer chest either forms part of the engine valve chest or is
bolted thereto, the steam from the boilers passing through said dryers on its way
to the engine.
A second dryer is fitted in between the high pressure and intermediate cylinder
in like manner, the chest of dryer either torming a distance piece between
the valve chests of the cylinders or the cylinder valve chests are enlarged and
the heater coils or tubes fitted therein, the valve chest chambers taking the
place of the dryer chest.
A third dryer is fitted in between the valve chest of the intermediary cylinder
and the third or low pressure cylinder valve chest by the chest of the dryer
either forming the channel for the passage of the steam from the one, cylinder
to the other or said dryer may form a distance piece on said connecting steam
pipe or channel.
When there are more cylinders than three as in the case of the quadruple
expansion engine, a fourth heater is interposed in like manner.
The exhaust steam from the low pressure or terminal cylinder enters a feed
water heater where it gives up part of its super-added heat before passing into
the condenser.
Said water heater preferably consists of a series of tubes fitted inside chambers
of like design and construction to the surface condenser presently in use, the
exhaust steam either passing inside or outside the tubes as may be found most
convenient. I do not confine myself to this particular type of water heater
but may use any analogous form of heater in general use, or there may be a
series of such heaters, one behind the other.
A check valve or valves are fitted to the exhaust pipe or channel intermediate
to the aforesaid heater and the condenser, loaded to prevent the exhaust steam
falling to the same pressure as that existing in the condenser, with the object of
obtaining a higher temperature in the water heating chamber than that existing
in the condenser.
A modification of the aforesaid system of drying the steam consists in taking
the steam direct from the main steam boilers and when the pressure in these
boilers is too high to pass direct into the high pressure cylinders to reduce the
pressure by means of a reducing valve.
In applying the aforesaid system of drying steam to expansion turbine
'engines, steam heaters are placed in front of the high pressure turbine for the
steam to pass through and between each succeeding turbine in precisely an
analogous manner to that described for reciprocating engines.
TL:
" 3000

page_text: to be performed, to be particularly described and ascertained in and by the
following statement:―
It relates to improvements in steam engines more particularly of the multi-
cylinder expansion type wherein the steam expands while doing work through
two or more cylinders on its way to the atmosphere or condenser. Said
improvements essentially consist in drying the steam while flowing from the
steam boilers to the engines and while passing from one cylinder to another by
the agency of steam generated in an independent or auxiliary boiler working
under a higher pressure than the main boiler or boilers for supplying the steam.
to actuate the engines, the heat being transferred from the higher pressed steam
to the steam for the motor by the agency of tubular or other type of heaters, the
condensed steam flowing back to the auxiliary boiler by the action of gravity.
The effect of this application of a high pressed circulating fluid is that the steam
from the main boiler is less liable to condensation and better results are obtained
in the motor while the extent of the drying or superheat can be regulated with
comparative precision.
In carrying my aforesaid invention into practice say in its application to the
present type of marine engine known as the triple or quadruple cylinder
expansion engine an auxiliary or independent generator preferably of the
water tube type is first constructed to work under a comparatively high pressure
say from one to two tons per square inch. This independent high pressure
generator is not strictly a steam boiler being more of a circulator of steam and
water and may be more correctly termed a heater, the steam generated being
utilized in heating or drying the motor steam in its passage from the boilers
proper to the engines, the condensed steam from the driers falling back into
the high pressure generator or heater by the action of gravity.
The aforesaid heater is provided with one or more outlets for the escape of
the steam or water to the steam driers and it is also provided with inlets to
permit the condensed steam or water returning on completing its circuit. It
may also in addition be provided with safety valves which either discharge
into the atmosphere or into the main boilers or the main boiler connecting pipes.
The steam generated from the water in the aforesaid high pressed heater is
conveyed by suitable tubing to steam driers or superheaters located at or near
the engine cylinders through which superheaters the steam from the main
boilers How to the high pressure cylinder and also from the one cylinder to its
succeeding neighbour. Said driers or superheaters preferably consist of the
well known tubular type wherein the steam in its passage to the engine cylinders
flows through a series of tubes fitted inside a hollow cylindrical casing, the
heating fluid enveloping these tubes but confined within the walls of the cylinder.
The steam from the high pressed heater referred to enters the upper part of
said casing which being in communication with the heater by means of a second
and lower outlet any steam condensing or liquefying inside the superheater
cylinder falls by the action of gravity through suitable tubes back into the
high pressed heater ready to be again reconverted into steam.
I do not confine myself to any one particular type of superheater and these
may be constructed in a variety of forms with the heating steam circulating
inside tubes which are enveloped by the steam to be heated and which is confined
in cylindrical chambers. The heater may consist of annular pipes with the
heating steam in the annular or jacketted space and the engine steam flowing
through the central channel, the annular pipe forming a distance piece in the
line of steam piping.
The engine cylinder valve chests may be converted into superheaters by
the covers being jacketted or having recesses in their bodies made steam tight
by an additional cover. The chest covers may likewise be fitted with nests of
tubes radiating at right angles into the valve chest, one end of the tubes being
open and screwed into the cover, the opposite end being sealed to prevent the
escape or leakage of the heating steam into the chest. The jacketted space in

page_text: the valve chest cover is in communication with the high pressed heater by
means of steam and condensed steam pipes.
When the main boilers or generators for supplying steam to the motors work
at a greater pressure than the engines, the pressure being lowered by the inter-
position of reducing valves the independent high pressure heater may be dis-
pensed with and instead the high pressed steam be taken from the generators to
the driers or superheaters located between the reducing valves and the engines,
the condensed steam returning to the generators by means of return pipes common
to the superheater and the generator.
Having now particularly described and ascertained the nature of my said
invention, and in what manner the same is to be performed, 1 declare that what
I claim is:-
1. In improvements in steam motors the means of utilizing the steam from
an auxiliary higher pressed boiler or heater to dry or superheat the steam on
its way to the motor substantially as herein before described.
2. In multi-cylinder steam engines the arrangement of re-heating or re-drying
of the steam flowing from one cylinder to another by the agency of steam
generated in an independent higher pressed boiler substantially as hereinbefore
described.
3. In steam engines working under a reduced pressure by means of a reducing
valve located between the generators and the motors, the utilization of the
steam under the initial pressure to dry or superheat the steam on the low
pressure side of the reducing valve by means of the apparatus substantially as
herein before described.
e
1000