US1943860A

US1943860A - Marine power plant

Info

Publication number: US1943860A
Application number: US305504A
Authority: US
Inventors: Warren B Flanders
Original assignee: Westinghouse Electric and Manufacturing Co
Current assignee: CBS Corp
Priority date: 1928-09-12
Filing date: 1928-09-12
Publication date: 1934-01-16
Anticipated expiration: 1951-01-16

Description

Jan. 16, 1934. w B FLANDERS 1,943,860

MARINE POWER PLANT Filed Sept. 12, 1928 1'0 Source 0/ A fluid Erasure f 36 ASYERN 45 AHEAD ASTERN SE(TION SECTION 89 TU INE INVENTOR 'IZ W-B-Flunders C1, 6 WWW 4e F'LQ.Z. v ATTORNEY Patented Jan. 16, 1934 UNITED STATES PATENT OFFICE MARINE POWER PLANT Application September 12, 1928 Serial No. 305,504

6 Claims. (Cl. 60-21) My invention relates to a marine propulsion arrangement, and it has for its object to provide a reciprocating engine and a low-pressure turbine disposed in compound relation in order to secure efficient utilization of energy of steam and rapid reversal.

In view of the fact that steam turbines are practically capable of expanding steam to lower absolute pressures than reciprocating engines, it 1 has been recognized that low-pressure turbines might be used advantageously with reciprocating engines. Such an arrangement, however, is subject to operating difficulties in marine service. While the low-pressure turbine may have ahead and astern sections capable of alternate connection to the reciprocating engine, dependent upon whether it is desired to operate ahead or astern, nevertheless, when changing over from ahead to astern operation, or vice versa, the passage of steam from the reciprocating engine may be greatly diminished or entirely interrupted for a certain length of time. This, together with the inertia of moving parts of the turbine apparatus, makes reversal somewhat difiicult and slow.

In accordance with my invention, I provide means for supplying high-pressure steam to the turbine sections, such means being under the control of the reversing mechanism of the reciprocating engine, whereby, when the reversing mechanism is operated, high-pressure steam is admitted to the proper turbine section. In this way, immediate admission of high-pressure steam to a turbine section serves to overcome the inertia of the rotor and connected parts and to secure reversal thereof very quickly.

Apparatus made in accordance with my invention is illustrated in the accompanying drawing, forming a part of this application, in which:

Fig. 1 is a diagrammatic View of my improved power plant;

Fig. 2 is a diagrammatic view showing a modified arrangement, having automatic control mechanism for admitting high pressure steam during reversing operation and for shutting off the same when the reversing operation is completed; and

Fig. 3 shows a detail of the control mechanism of Fig. 2 in different position.

r Referring now to the drawing more in detail, I

0 show a multiple expansion reciprocating engine,

at 10, driving a propeller shaft 11, having a propeller 12 connected thereto. High pressure steam from any suitable source, such as boilers (not shown) is supplied through the conduit '7. A conduit 8, connecting therewith, passes the steam to the inlet of the reciprocating engine, and interposed in the conduit 8 is a throttle valve 9 for controlling the supply of steam to the reciproeating engine.

Steam exhausted from the engine 10 is supplied by a suitable line 13 to a low pressure turbine 14. After energy is abstracted from the steam by the turbine 14, the exhaust passes to the condenser 15. The rotor of the turbine is connected to the shaft 16, the latter entering the casing 17 of a suitable reduction gear and being connected to a pinion 18 meshing with the gear 19 carried by the shaft 11. The turbine 14 includes an ahead section 20 and an astern section 21 so that the turbine is capable of operation in either direction to secure ahead and astern propulsion.

The exhaust line 13 from the reciprocating engine is connected to branches 23 and 24 leading, respectively, to the ahead and astern turbine sections 20 and 21. A high-pressure steam line 25, communicating with the conduit '7, is provided with branches 26 and 27 leading, respectively, to the forward and astern sections 20 and 21. Valves 28, 29, 30 and 31 are arranged so in the

branches

23, 24, 26, and 27, respectively, and such valves are connected to mechanism at 32, which is operated by the engine reversing lever 34. The latter also operates the reversing mechanism 33 of the reciprocating engine. On the drawing, the reversing mechanism 33 has been moved from its correct position with relation to the reciprocating engine in order to show its operative relation to the mechanism 32.

While the interconnecting mechanism may take any suitable form, I show, ,by way of example, reversing mechanism including a lever 34, which is connected to a link 35, the latter being pivoted to a lever 36 and the lever being connected to a link 3'7. The link 37 is connected to suitable crank arms carried by the valves. A valve 38 is provided in the high-pressure steam line 25 and it is positioned conveniently to the reversing mechanism 33 for a purpose to be hereinafter explained.

The operation of the apparatus described is as follows: Assuming that the reciprocating engine, at 10, and the turbine, at 14, are in operation and it is desired to reverse them, the reversing mechanism 33 is operated and this, through the linkage 32 serves to open one of the valves 30 and 31 and to close the other, thereby admitting high pressure steam to the turbine to reverse its direction. During the period of reversing of the reciprocating engine the flow of steam therethrough is limited by the speed at which the pistons move. Also, the rotor of the turbine has considerable inertia in the direction of its rotation prior to reversal. Hence, the prompt admission of high pressure steam to the proper turbine section serves to overcome rapidly the inertia of the turbine and to reverse it quickly.

The valves 28 and 30 are arranged to open and to close together and the same is true of the valves 29 and 31. When the reversing mechanism 33 is operated, one pair of valves is opened while the other is closed. Hence, with the admission of high pressure steam to a turbine section, the corresponding valve controlling the admission of exhaust steam to the same section is opened, the high-pressure steam coming into action promptly as above pointed out. After reversal has been eifected and there is normal flow of exhaust steam in the line 13, the supply of high-pressure steam may be shut off by closing the valve 38. If this is done, the valve should be again opened before reversing.

In Fig. 2, I show a modification of my inven tion, wherein a reciprocating engine 10 and a turbine 14 are geared for driving a propeller 12, as in the first embodiment. In this embodiment however, automatic or governor controlled means are provided for admitting live steam to the turbine for reversing the direction of rotation, and for automatically shutting elf the sup ply of live or high-pressure steam when the turbine has attained a predetermined speed in the desired direction. Such parts of this embodiment as are also found in the first embodiment are designated by the same reference numeral.

Exhaust steam from the reciprocating engine is passed to the ahead section of the turbine, during ahead operation, through the conduit 13 and a branch conduit 23a. In this case, exhaust steam is not used in the astern section 21, and, therefore, a branch conduit 24a leads from the conduit 13 to the condenser 15. A two way valve 41 is provided at the connection between the branches 23a and 24:]. with the conduit 13, and is adapted to place the conduit 13 in communication with either of said branch conduits. two way valve 41 has a crank arm 42 for operation thereof, the latter being connected with the reversing mechanism 33 through a rod 91, a bell crank lever 92, and a rod 8'7.

To obtain a governing fluid pressure which will control the admission of high-pressure steam to the turbine 14 until the turbine has attained the desired speed in the desired direction, a. gear pump 43 is provided, said pump being driven by the turbine 14 in any suitable manner, at a speed proportional to the speed of the turbine, and in a direction determined by the direction of rotation of the turbine shaft. In the construction shown on the drawing, the gear pump is connected with the turbine shaft 16 through a beveled gearing 43'. The gear pump is so arranged that when the turbine is rotating in ahead direction, fluid under pressure is transmitted to a conduit 44, and when the turbine is operating in astern direction, the pump passes fluid under pressure to a conduit 45. A reservoir 46 contains a body of any suitable lieuid, preferably lubricating oil, and a conduit 4'7 communicates with the bottom thereof. The conduit 4'7 communicates with the

conduits

44 and 45, at points near the gear pump 43, through the branch conduits 48 and respectively. Check valves 51 and 52 are provided in the

branches

48 and 49, respectively, thereby permitting the gear pump to draw liquid from the reservoir 46, but preventing the loss of fluid pressure thereto.

A conduit 53, communicating with the conduit 44, has a restricted orifice 54 therein, and a conduit 55, communicating with the conduit 45, has a restricted orifice 56 therein. The conduit 53 communicates with the conduit 55 beyond the orifices, and the conduit 55 communicates with the reservoir 46. The

orifices

54 and 56 permit the escape of excess liquid to the reservoir 46, imposing a pressure on the liquid, how ever, which is a function of the speed of the gear pump 43. It will thus be seen that when the turbine 15 is operating in ahead direction, the gear pump 43 provides a fluid pressure in the conduit 44 which is a function of its speed, and when the turbine is operating in astern direction, the gear pump provides a fluid pressure in the conduit 45 which is a function of its speed.

The supply of high-pressure steam to the ahead sec ion in this embodiment is controlled by a valve 61 interposed in the conduit 26, and the supply of high-pressure steam to the astern section is controlled by a valve 62 interposed in the conduit 2'7. The valve 61 is actuated by a piston 63 operating in a cylinder 64. A spring 65 biases the piston 63 to open the valve 61.

The valve 62 is operated by a similar piston 66 operating in a cylinder 67 and also biased to open lie valve by a spring 68. A conduit 69 communicates with the cylinder 64 for supplying actuating fluid thereto, and a conduit '71 communicates with the cylinder 6'7 for the same purpose.

The supply of fluid pressure from the

conduits

44 and 45 to cylinders 64 and 67 for operating the valves 61 and 62, is controlled by a pilot valve '72, which, in turn, is actuated by the re versing mechanism 33 of the reciprocating engine 10 through the rod 8'7, a bell crank lever 88, and a rod 89. The pilot valve '72 has piston portions '73, '74, '75 and '75, and operates in a cylindrical valve casing '77. The pilot Valve '32 is shown in Fig. 2 in the position corresponding to neutral position of the reversing mechanism 33.

The conduits '71 and 69 communicate with the casing '77 at points intermediate the piston portions '74 and '35. but adjacent to these piston portions, respectively. The

conduits

45 and 44 communicate with the valve casing '77 at points which are always in communication with the space between the piston portions '73 and '74 and between the piston portions '75 and '76, respectively. A conduit '78, which furnishes from any suitable source liquid pressure of a value sufficient to close each of the valves 61 and 62. communicates with the casing '77 at a central point, and is always in communication with the space between the piston portions '74 and '15.

A throttle valve 81 is preferably interposed in the cond it 25 between the conduit '7 and the branch conduits 26 and 2'7. This valve is ac tuated by a piston 82 operating in a cylinder 83. The piston 82 is biased in a direction to close the valve 81 by a spring and the conduit 753 communicates at the lower end of the'cylinder 83, admitting fluid pressure thereto in a direction to open the valve against the force of the spring 84. A stem 85 is screw-threaded through the upper end of the cylinder 83 and is adapted to operate the piston 82 against the fluid pressure by means of a handwheel 86 attached thereto.

The operation of this embodiment of my in vention is as follows:

Assume the apparatus is to be in ahead operation.. The throttle valve 9 is open and the reversing mechanism 33 is in ahead position in which the rod 8'7 is at the right-hand end of its travel. The

rods

91 and 89 are at the upper ends of their travel, the former maintaining the valve 41 in position to close communication with the branch conduit 24c and to permit the exhaust steam from the engine 16 to pass to the ahead section of the turbine.

The rod 89 holds the pilot valve '72 in its upper position, as shown in Fig. 3. The conduit 69 is in communication with the conduit 44, and iluid pressure from the gear pump 43 is, therefore, imposed on the piston 63 to close the valve 61. The conduit 71 is in communication with. the conduit '78 which provides fluid pressure to close the valve 62.

In normal ahead operation, therefore, only exhaust steam from the reciprocating engine is admitted to the turbine and, therefore, the most econmical operation of the apparatus is obtained.

Suppose now that it is desired to reverse the direction of operation. The throttle valve 9 is closed to shut off the supply of steam to the reciprocating engine. The reversing mechanism 33 is actuated by means of the lever 34 to astern position, the rod 87 being moved to the left and the

rods

91 and 89 being moved to lowermost position. The throttle valve 9 is again opened. The valve 41 closes communication with the ahead section and the exhaust steam from the engine is passed to the condenser 15 through the branch conduit 24a.

The pilot valve 72 is also moved to lowermost position by the rod 89, the piston portion 74 being disposed between the ports communicating with the conduits '71 and '78. The

conduits

78 and 69 communicate through the space be tween the piston portions 74 and l5, and fluid pressure from the conduit 78 is, therefore, communicated to the piston 63 to retain the valve 61 in closed position.

The conduit 71, however, is placed in communication with the conduit 45, through the space between the piston portions 73 and J4, and as the turbine is operating in ahead direction, there is no pressure in the latter conduit. The spring 68, therefore, moves the piston 66 to open the valve 62, and high-pressure steam is admitted to the astern section of the turbine. This steam quickly brakes the speed of the turbine in ahead direction, and then quickly accelerates it in astern direction. As the turbine attains a predetermined speed in astern direction, the pressure developed by the gear pump in the conduit 45 acts on the piston 66 against the force of the spring 68 and shuts the valve 62.

The apparatus is now maintained in astern operation by the action of high pressure steam on the reciprocating engine, and no power developed by the turbine.

It will be apparent, however, that the spring 68 (or the orifice 56) may be so designed or the orifice 56 may be so adjusted that high-pressure steam may be normally admitted to the astern section 21 during astern operation, if this is desired.

Assume now, that it is desired again to reverse and resume ahead operation. The throttle valve 9 is closed, the reversing mechanism 33 again moved to ahead position, and the throttle valve 9 again opened. The valve 62 is held closed above described, but the valve 61 is opened due to the absence of pressure in the conduit 44.

High-pressure steam is, therefore, admitted by the valve 61 to the ahead section of the turbine, until the desired ahead speed is obtained, when the pressure in the conduit 44 moves the piston 63 to close the valve 61.

Should the auxiliary source of fluid pressure transmitted through. the conduit '78 fail for any reason, the spring 84 would move the piston to close the throttle valve 81, thereby shutting oiT all supply of high-pressure steam to the turbine, which would otherwise be permitted, due to the action of the springs and 68.

It will be seen that in this embodiment, the high-pressure steam is automatically admitted to the turbine to obtain a quick reversal of the direction of operation, only a normal operation of the throttle valve and reversing mechanism of the reciprocating engine being necessary.

From the foregoing, it will be apparent that I have devised a marine propulsion organization employing a reciprocating steam engine and a turbine arranged in compound relation with means for securing quick and positive reversal of the organization, thereby overcoming a disadvantage heretofore present due to slow reversal.

What I claim is:

1. The combination with a reciprocating engine having a reversing mechanism, a turbine having ahead and astern sections, and means for supplying steam exhausted from the reciprocating engine to the turbine, of means for supplying high-pressure steam to the ahead and astern sections and controlling means for the last-named means connected to said reversing mechanism, whereby, when the reversing mechanism is operated to change the direction of the reciprocatingengine, high-pressure steam is admitted to one of the turbine sections to change the direction of the turbine, said controlling means being operative to shut off the admission of high pressure steam to the turbine in response to a pre-determined speed thereof.

2. The combination with a reciprocating engine having a reversing mechanism and a turbine having forward and reverse sections, of first passages for supplying steam exhausted from the reciprocatin engine to the forward turbine section, second passages for supplying high-pressure steam to the turbine sections, valves in said first and second passages, and means connected to the valves and to said reversing mechanism to secure admission of high-pressure and exhaust steam to the ahead section or of high pressure steam to the astern section dependent upon the position of the reversing mechanism and responsive to a pre-determined speed of the turbine for shutting oil admission of high pressure steam thereto.

3. In a marine propulsion power plant, the combination of a reciprocating steam engine having a reversing mechanism, a turbine having ahead and astern sections, means for supplying exhaust steam from the reciprocating engine to the ahead section, means for supplying high-pressure steam to said ahead and astern sections, and means responsive to operation of said reversing mechanism for interrupting the supply of steam to one section and for rendering the high-pressure steam supply means effective for supplying high-pressure steam to the other section, and for interrupting the supply of high pressure steam to said other section in response to a pre-determined speed.

4. In a marine propulsion power plant, the combination of a reciprocating steam engine having a reversing mechanism, a turbine having ahead and astern sections, means for supplying exhaust steam from the reciprocating engine to the ahead section, means for supplying high-pressure steam to the astern section, means responsive to operation of the reversing mechanism in changing the reciprocating engine from ahead to astern operation to interrupt the supply of exhaust steam to the ahead section and tc render effective the means for supplying high-pressure steam to the astern section, and means responsive to the speed of the turbine for shutting off the supply of highpressure steam.

5. In a marine propulsion power plant, the combination of a reciprocating steam engine having a reversing mechanism, a turbine having ahead and astern sections, means for supplying exhaust steam to the ahead section, means for supplying high-pressure steam to the ahead and astern sections, means responsive to operation of the reversing mechanism in changing the engine from ahead operation to astern operation for interrupting the supply of exhaust steam to the ahead section and for rendering the high-pressure steam supply means effective for supplying high-pressure steam to the astern section and responsive to operation of the reversing mechanism in changing the engine from astern operation to ahead operation for rendering both of said steam supply means effective to admit exhaust and high-pressure steam to the ahead section, and means responsive to speed of the turbine for shutting off the supply of high-pressure steam.

6. The combination with a reciprocating engine having reversing mechanism and a turbine operated by exhaust steam received from the reciprocating engine, of means for supplying highpressure steam to the turbine, and means responsive to operation of the reversing mechanism for rendering the high-pressure steam supply means effective and means responsive to the speed of the turbine for rendering the same ineffective.

WARREN B. FLANDERS.