US1153475A - Marine turbine. - Google Patents

Description

K. AL QUlST I MARINE TURBlNE. APPLICATION FILED JAN.20, 1315.

1,153A?58 P atentedsept. 14, 1915.

Inventor: Kar! o l uisL, f I,

Him

' driven Tat full, 1 intermediate or cruising cents. I

KARL ALQUIST, OF SCHENEGTADY, NEW YORK, ASSIGNOR TO EENERAL ELECTRIC COMPANY, A CORPORATION OF NEW YORK.

MARINE TURBINE.

Specification of Letters Patent.

Patented Sept. 11a, 1915.

Application filed January 20, 1915. Serial a... 3,254.

To all whom it mag concern:

Be it known that I, IxAnL AL UIs'r, a

. subject of the King of Sweden and Norway,

residing at Schenectady, county of Schenectady, State of New York, have invented certain new and useful Improvements in Marine Turbines, of which the following is a specification.

The present invention relates to turbines for propelling vessels, and in particular to those intended for war vessels Which, for i the greater part of thetime, are operating .7 at cruising speed, but are at times required to operate at.higher or maximum speeds.

The purpose of my invention is to provide an arrangement or grouping of turblnes for propelling a vessel, and in particular one having twin'screws or propellers, which, by changing the number of turbin'es in service and the manner in which they receive steam or other elastic motive fluid, can be made to operate with hlgh economy at maximum, intermediate, and

cruising speeds.

-.F or a consideration of what I belleve to be novel and my invention, attention is ditem of turbine propulsion for vessels; Fig. 2

is a diagrammatic illustration of a main and a cruising turbine;' F 1g. 3 1s a dlagrammatic detail view of the main and auxlhary .nozzles; Fig, 4 is a detail view of a double seated valve for controlling the admission of steam to the maln and cruising turbines, and Figs. 5 to 7 are dlagrammatic views illustrating the flow of steam to the turbines under difierent operating conditions.

2 and 3 indicate twin main turbines for propelling the vessel at maximum speed,

3 I While the turbine can be eachof which drives a propeller shaft 4: either directly or through speed reducing gearlng 5. The latter arrangement s prefl erable because the propellennfi can be- .driven at its nfost favorable effective speed, I made relatively small and light and operated at a high and most "favorable. speed, thereby obtaining OOd economy of operation. :By arranging the gearing in the position shownitis al- 'ways in. service whether, ,.the ship isibeing': the. auxiliary set of nozzles 16 in each main turbine is cut out pf service. They are, 116

turbine has a forward speed. I have not illustrated the gearing in detail because its specific constructionforms no part of the present invention. In other pending applications I have disclosed gearing suitable for this purpose. The turbines operate on the impulse plan and are preferably of the Curtis type because of their high economy and decreased weight and moderate speed for a given output. Each driving element 7, Fig. 2, comprising in the present instance one or more wheels 8 having a plurality of rows of peripheral buckets and one or more wheels 9, each having a single row of peripheral buckets, said'wheels being mounted on the shaft 10. In the rear end of each turbine casing is located a reversing element 11 comprising one or more bucket wheels mounted on the shaft 10. Both the forward driving and reversing elements exhaust into condensers 12. The extracting capacity of turbine buckets depends roughly on the square of their speed. That is to say, if the bucket speed be decreased onehalf the energy range for equal extracting efficiency thereof will be reduced to about I one-fourth, hence the importance of increasing the number of stages for reduced speed operation,a feature which will be referred to later.

Each main turbine is provided with a set of nozzles 13 adapted in size and shape to .receive high pressure boiler steam from the supply main 14 and convert a predetermined percentage of its pressure into velocity, which in turn is converted into useful Work by the rotating element, as is Well understood Between the various bucket wheels,

each in a'stage of its own, are stage nozzles 15 for converting pressure into velocity and conveying steam between the stages in a manner Well understood. Each turbine is also provided with an auxiliary or lOW pressure set of nozzles 16 adapted in shape and size to receiveexhaust steam from a cruising turb ne, to be described later, and convert a predetermlned percentage of 1ts pressure into velocity, Which in turn is converted into useful work. by the rotating element. The

main and auxiliary nozzles receive their supplies ofsteam from separate chests, the purposefof which will be referred to later. When operating at full speed and power however, in service for cruising speed conditions. For full and high intermediate speed conditions the main admission nozzles only are in service. The main turbines are designed to give their maximum economy at nearly full or full speed'of the ship.

Situated in line with the main turbines.

and preferably forward thereof to facilitate cutting the same into and out of service, are auxiliary or cruising turbines 17 and 18 that-are adapted to be connected to and disconnected from the main turbine shafts by releasable clutch couplings 19 and 20. These turbines are provided with bucket wheels of such diameter as to etlicient-ly extract energy from the steam at lower speeds of the ship. They may be uncoupled from the'main turbines when the'latter are operat-' predetermined percentage of pressure into 'separate auxiliary nozzles 1(3 of the main velocity which in turn is extracted by the buckets of the rotor. They exhaust into the turbines and are adapted to extract only a portion of the total energy of tl, ie steam at any time. If the same'nozzles were used in the main turbine for boiler steam and also for exhaust steam from thecruising turbine, whenever boiler steam was admitted to the chest supplying saidnozzles it would also flow back into the shell of the cruising turbine and in thismanner subject it to very high stresses. This could be avoided by using a valve in the conduit between the two shells but there would still be the danger of the operator neglecting to close it which is avoided by my improved construction. Further it would require an additional operation which I avoid.. ()ne of the cruising-turbines is also provided with an auxiliary or low pressure set of nozzles 18, resembling the. other nozzles in general construction. which is put into service only for low speed cruising coiu'litions when the two turbines are seria ll y arranged as regards the passage of steam, as will appear later in connection, with Fig. 7. When the. cruising turbines are operating in seriesas regards the passage of steam t'l'ieuna-iir rim-lame are connected in parallel as regards the passage of steam; the various groups of admission and stage nozzles being plroportioned in a manner well understood giye the desired tion the valvef30 will shu .ofi' the flow of steam cruising tulrh ne 17 to main work division.

High pressure or boiler steam is admitted to the main turbines in parallel for high speed propulsion by the conduit ll subject to the control of throttle valves 23 and 2*. High pressure or boiler steam is admitted to the auxiliary or cruising turbines-by the conduit 14. subject to ,the control of the throttle valves 26 and 27. The exhaust steam from the cruising turbines 17 and 18 enters the main turbines Z and 3 by the conduits 2S and 29 subject to the control of valves 30 and 31.- Valve 30 may with advantage be of the construction shownin Fig. 4c. The valve is' of the doubleseat type and is operated by the usual nut and screw 32, there being a hand wheel 33 on the valve spindle. When the valve is raised all the steam passes to the main'turbine and when lowered it all passes to the cruising turbine. By using a valve of this character. one of the'exhaust pipes always remains open and thus prevents any abnormal rise of pressure in the shell of the cruising turbine 17. It also enables me. to reduce the total number of the valves required.

In Fig. 5 is shown diagrammatically the relation of parts for high speed operation of the vessel, for example 25 to 30 knots. The cruising turbines are mechanically disconnected from the main turbines by opening the clutches 19 and 20 and all steam is shut off therefrom by closing the supply valves 26 and 27. The auxiliary nozzles 16 ofthe main turbines are also inactive and valves 3Q and 31 are shut. High pressure steam is admitted to both turbines in parallel from the main 1l,'the throttle valves 23 and 2t being open to the desired extent.

In Fig. 6 is shown diagrammatically the relation of parts for medium or intermediate speeds of the vessel. In this figure 'the main and cruising turbines are operating together, the parts of the clutch couplings 19 and 20 being united. lligh pressure steam is admitted in parallel to the starboard and port I turbines, the exhaust from the cruising turbines passing through the conduits 28 and 29 to auxiliary sets of nozzles 16 into the main turbines. the latter exhausting into the condensers. This arrangement is adapted to operate at its best etliciency for an intermediate. speed of thevessel of, say 20 knots.

In Fig. 7 is shown diagrzumnat-ically the relationof parts for low speed or cruising operation of the vessel. Illthis figure the cruising turbines are connected in series as regards the passage of steam. and the two main turbines are connected in parallel as regards the passage of steam. both operating on the exhaust steam from the cruising tur-- billes. This arrangement'is adapted for low ...speeds of the vessel, say 12 to 16 knots for example. mUnaler this. condition of opera- Y being sufficient for pressure nozzle 16 of the second main turbine 3. Under these conditions the valve 31 occupies a mid position.

As an illustration of my invention, but not as a limitation thereof, the following outputs and speeds may be considered as typical of the conditions for each propeller:

Propeller Horse revolutions Knots. power. per minute.

The illustration above given clearly shows the very great difference in shaft horse power between a vessel operating at maximum speed and the same vessel operating at low or cruising speeds. It also makes apparent the very great necessity of so arranging or combining the turbines in difierent ways or groups so that they can economically utilize the motive fluid at different speeds of the vessel. My improved arrangement contemplates three principal speeds of the vessel-high, intermediate, and low, at which a high degree of economy in the use ofsteam or the motivefiuid is-efiected, these the great majority of cases. For speeds other than those specified I can resort to cutting nozzles out of service, as by the valves 36, especially for the main turbines, or by throttling the supply of bines can be put steam. As a general proposition the feature of cuttlng-nozzles into and out of service will be limited to the high pressure portions of the installation and throttling to the low pressure portions, although in some instances either or both modes of control may be employed.

The principal advantage of my improved arrangement resides in the fact that the vessel can be operated economically at the three speeds most often required, thereby.

increasing its radius of operation. This primary advantage is brought about by the fact that the main turbines with their main admission nozzles can be designed to give their best efliciency at high speeds, that for inter-.

mediate speeds additional and efiicient turinto service so that a greater number of wheels or rows of buckets can be employed'whereby they will have substantially the same total extraction efficiency, but

at a lower speed with a lower total steam are designed for,

.main turbines to mum speeds,

maximum,

speeds of the ship.

combination .,pr'opel the ship at maximum speed,rnam and volume. This is in part due to the use of auxiliary nozzles which are properly de the passage'of steam and hence a lower speed of the vessel is obtained with a corresponding lower shaft speed and a decrease in total steam volume without substantialsacrifice in economy of operation.

By employing cruising turbines arranged in the manner described I reduce the losses when the vessel is operating at full speed because the cruising turbines do not form a dead load on the main turbines, and I may further avoid the danger due to operating said turbines under greater speeds than they and because of this turbines pf less expensive construction may be used.

In accordance with the provisions of the patent statutes, I have described the princlple of operation of my invention, together with the apparatus which I now consider to represent the best embodiment thereof; but I desire to have it understood that the apparatus shown is only illustrative, and that the invention can be carried out by other means.

What I claim as new and desire to secure by Letters-Patent of the United States, is

1. In a system of combination of main turbines arranged to propel the ship at maximum speed, cruising turbines arranged to cooperate with the propel the *ship' atspeeds below the maximum, and means arranged to connect the cruising turbines in series with the main turbines as regards the flow of steam for intermediate speed conditions and to connect the cruising turbines serially as regards the flow of steam and to supply the exhaust therefrom to the main turbines in parallel for lower speeds of the ship.

2. In a system of ship propulsion, the

combination of propeller shafts, main 'turbines arranged to propel the ship at maxispeed reducing gearing between the turbine and propeller shafts, cruising turbines arranged to be connected to the main turbines and cooperate therewith to propel theship at speeds below the releasable couplings between the shafts of the main and cruising turbines, and means arranged to connect the cruising turbines in series with the main turbines as regards the flow of. steam for intermediate ship propulsion, the.

speeds oftlre ship-and to connect the cruising turbines serially as regards the flow of steam and t6 supply the exhaust therefrom to the main turbines 3. In asystem ,of ship propulsion, the of main turbines arranged to in parallel for weer are main turbines in parallel for lower speeds of the ship.

4:. In a twin screw system of ship propulsion, the combination of twin propeller shafts, two main turbines for driving the ship at full speed, speed reducing gearing between each turbine and its corresponding propeller shaft, two cruising turbines, releasable couplings for connecting the shafts of the cruising turbines tothose of the main turbines, and means'for connecting the cruising turbines in series as regards the flow of steam with the main turbines .for 'certain' speeds of the ship and for connecting them in series as regards the flow of steam and to exhaust into the main turbines for certain other speeds of the shin.

In a system of ship propulsion, the combination of propeller shafts, main turbines coupled thereto for propelling the ship at maximum speed, cruising turbines each having a separate casing and whose rotor is coupled to the respective main turbine shaft for cruising speeds, all of said turbines being provided with nozzles so proportioned as to give the desired work division, meansfor connecting the cruising turbines to and disconnecting them from the main turbines, conduit means for connecting each cruising turbine in series with a main turbine and for connecting the cruising turbines in series with each other as regards the flow of motive fluid and to exhaust into both main turbines, and valves in said conduit means for' ,controlling the passage of motive fluid therethrough.

Copms of this patent may be obtained for five cents each, by addressing Washington, D. 0.

6. In a system of ship propulsion, the combination of propeller shafts, condensing main turbines coupled thereto for propelling the ship at maximum speed, cruising turbines having separate casings whose rotors are in line with the shafts of the main turbine and are coupled thereto for low speeds only of the ship, all of said turbines being provided with nozzles so proportioned as to give the desired work division, releasable couplings between the main and cruising turbines, conduits for admitting live steam to the main turbines for high speeds and to the cruising turbines for lower speeds, a conduit connecting the exhaust of one cru1sing turbine with the inlet of another, conduits for connecting the exhaust of the last named cruising turbine with the low pressure nozzles of the main turbines, and valve means controlling the passage of steam through the conduits. v

7. In a system .of ship propulsion, the combination of propeller shafts, condensing main turbines coupled thereto for propelling the ship at maximum speed, main and auxihary nozzles for sald turbines, cruising turbines having separate casings Whose rotors are coupled to the main turbme shafts for' low speeds only of the ship, main nozzles for the cruising turbines, an auxiliary nozzle for, one of said turbines, the nozzles of all of said turbines being so proportioned as to give the desired work division, releasable couplings between the main and cruising turbines, conduits admitting live steam to the turbines, aconduit for connecting the exhaust of one cruising turbine with the auxiliary nozzle 'of another \cruising turbine, conduits receiving the exhaust of the last named turbine and delivering it' to the auxiliary nozzles of-the main turbines, and valve means for controlling the passage of steam through the conduits.

In witness whereof, I have hereunto set my hand this 13th day of January, 1915.

- KARL 'ALQUIST. Witnesses:

HELEN Onronn,

MARGARET 1*.Woonnnr.

the Commissioner of Fatents,

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