US2064825A

US2064825A - Turbine

Info

Publication number: US2064825A
Application number: US42371A
Authority: US
Inventors: Warren B Flanders
Original assignee: Westinghouse Electric and Manufacturing Co
Current assignee: CBS Corp
Priority date: 1935-09-27
Filing date: 1935-09-27
Publication date: 1936-12-22
Anticipated expiration: 1953-12-22

Description

v w. s. FLANDERS 2,064,825

' TURBINE Dec. 22, 193

v Filed Sept. 27, 19:55

7 Fla 5.

INVENTOR. WHRREN Bfm/mms.

ATTORNEY Patented Dec. 22, 1936 UNITED STATfi QFFICE TURBINE of Pennsylvania Application September 2'7, 1935, Serial No. 42,371

10 Claims.

My invention relates to marine turbines having ahead and astern sections and it has for its object to provide means to limit the temperature of steam exhausting from the astern section in order to avoid structural distortion and excessive stresses which may occur because of excessive temperatures of such steam.

In the marine turbine art, it is common practice to design the ahead turbine section to secure most economical performance with steam supplied under given or existing conditions. Also, it is usual to supply steam from the same source or boiler to the astern section or sections. As an astern section is very muchshorter than an ahead section and is usually not as efficient, so far as converting heat energy into mechanical energy is concerned, it will be apparent that heat energy in steam supplied to the astern section -will manifest itself as superheat in the exhaust 20 even though the astern and ahead sections are designed to expand steam down to approximately the same absolute pressure. Excessive superheating of steam exhausting from the astern section, or relative high temperature of such steam, may be objectionable on account of the consequent localized heatingpf the turbine structure setting up distortion, differential expansion effects, and severe stresses. To avoid undesirable efiects of superheating, I bring a suitable medium, such as water, into heat transfer relation with respect to steam passing through the astern section in order to limit the temperature of such exhaust steam. Accordingly, a further object of my invention is to provide cooling apparatus arranged in this manner and for the purpose indicated.

A further object of my invention is to provide a marine turbine having ahead and astern sections with means for spraying water into steam passing through the astern section in order to limit the exhaust temperature of such steam.

A further object of my invention is to provide a marine turbine having forward and astern sections exhausting to a condenser together with a device for spraying water into steam passing through the astern section in order to limit the exhaust temperature of such steam, the spray device being supplied with condensate from the condenser.

A further object of my invention is to provide a marine turbine having forward and astern sections and a device for supplying a spray of water to the steam passing through the astern section in order to limit the exhaust temperature of such steam, the valves controlling the supply of steam to the astern section and of water to the spray device being interconnected so that operation of the astern steam valve will result in operation of the water valve.

These and other objects are effected by my invention, as will be apparent from the following description and claims taken in connection with the accompanying drawing, forming a part of this application, in which:

Fig. 1 is a side elevational view of a marine turbine installation having my invention applied thereto;

Fig. 2 is a vertical transverse sectional view taken along the lines IIII of Fig. 1;

Fig. 3 is a longitudinal vertical fragmentary sectional view; and,

Figs. 4 and 5 are sectional views showing alternative locations of the spray device.

Referring now to the drawing more in detail, I show a marine turbine, at H], having a casing H including upper and lower parts l2 and I3. A rotor I4 is disposed within the casing.

Ahead and astern blading sections I5 and I6 are carried by the casing and by the rotor, the sections being supplied with steam by the conduits I! and I8, respectively; and, as shown in Figure 3, the sections are so arranged as to discharge into a common exhaust space enclosed by the casing.

The turbine, at In, is arranged to exhaust into a condenser 2| in the usual way, the condenser having a hot-well 22 from which condensate is removed by the pump 23 and discharged through a pipe 24 for return to the steam generating apparatus.

Since it is undesirable to construct the turbine any longer than necessary and since the astern section is used very little compared to use of the ahead section, it is the common and reasonable practice to make the astern section relatively much shorter axially compared to the ahead section, the astern section containing a relatively smaller number of rows of blades or energy-abstracting elements. Therefore, if the ahead section blading is designed to expand steam from boiler pressure down to a desired absolute or condenser pressure with a desired exhaust temperature, it will be apparent that, with steam supplied from the boiler to the astern section, even though the pressure may be reduced in the astern section to approximately the same value as the pressure of the ahead section exhaust, the heat energy in the steam will not be as efiiciently utilized or converted into mechanical energy, with the result that such heat energy will manifest itself as superheat in the steam exhausting from the astern section. Because of structural difiiculties which may be encountered on account of superheat, or high temperature, of steam exhausting from the astern section, I propose to bring a suitable medium into heat transfer relation with respect to steam passing through the astern section in order to limit the temperature thereof.

The temperature of steam exhausting from the astern section is preferably limited by means of a spray device 25 arranged so as todischarge a spray of water into steam exhausting from the astern section in order to limit the temperature of such steam. In Figs. 2 and 3, I show the spray device 25 supported interiorly of the casing l I, extending circumferentially of the exhaust ends of the blading sections and arranged so as to be out of the way of the steam exhausted from the latter. As shown in Figs. 2 and 3, the spray device is arranged radially outward from the exhaust end of the ahead section and is so disposed that the water jets 25 thereof may be directed rearwardly toward the exhaust end of the astern section in such manner that the spray may freely enter the common exhaust space 20 between the turbine sections and absorb superheat of steam exhausting from the astern section, the heat of superheat being used to heat and vaporize the water. Since it is customary tohave the turbine casing comprised by upper and lower detachablyconnected parts, I prefer to construct the spray device 25 in such manner that it is comprised by semi-circular tube sections 2? and 28 carried by the upper and lower case parts l2 and I3, respectively.

In Fig. 4, I show a modified form of spray device including a belt tube 29 encompassing the stator element 30 of the astern section I 6 and having spray openings 3| arranged to discharge water toward and into the space between the ahead and astern blading in order that steam issuing from the astern blading may be de-superheated.

Instead of having the spray device discharge a spray of water into steam exhausting from the astern section, as indicated in Figs. 2, 3, and 4, the spray device may be arranged to supply water into the steam before it is exhausted from the astern section with the result that superheating is limited. To this end, in Fig. 5, I show a tubular spray device 32 arranged to discharge jets of water into the steam issuing from the nozzles 32a of the astern section. Since the velocity of steam issuing from such nozzles is more than adequate for the blading, no material interference is set up because of water injection in this manner and at the same time the water so injected is efi'ective to limit the temperature of the exhaust.

Water may be supplied to the spray device in .any suitable manner; however, care should be exercised with respect to the temperature of the water if the invention is to be used to the best advantage, for, if the water temperature is appreciably below that of the temperature corresponding to the vacuum, there would be undesired chilling resulting in differential temperature effects on the structure similar to those already described. Furthermore, where a surface condenser is employed, as is usually the case with marine installations, the spray Water should be suitable for boiler feed; and, while any feed water having the desired temperature may be used, condensate froma surface condenser meets both the temperature and feed water requirements. The temperature of the water injected should approximate normal exhaust temperature of the ahead section. Consequently, I prefer to use condensate from the condenser in the spray device, the heat or superheat being absorbed by vaporization of the condensate and the latent heat of such vapor being carried away by the condenser circulating water in the usual way. In Fig. 1, I show a conduit 33 for supplying condensate to the spray device; and, since I prefer to have the spray device made into upper and lower parts, the conduit 33 has

branches

34 and 35 leading to the upper and

lower spray conduits

25 and 26.

It is desirable that the astern section and the spray device therefor shall be operated together. Accordingly, in Fig. l, I show the steam conduit It for the astern section provided with a control valve 35 which may be opened and closed by a suitable operating device 3i. Also, the condensate conduit 33 has a valve 38. Any suitable interconnecting mechanism, at 39, may be arranged between the valves 3? and 38 so that, when the valve 37 is open and closed the spray valve 38 will also be opened and closed.

Fro-m the foregoing, it will be apparent that I have devised a marine turbine arrangement wherein excessive temperature, or superheat, of steam exhausting from an astern section is avoided, this result being effected by means of water injected in the steam passing through the astern section, the water being vaporized by heat derived from the steam so as to limit the temperature of the latter.

While I have shown my invention in several forms, it will be obvious to those skilled in the art that it is not so limited, but is susceptible of various other changes and modifications without departing from the spirit thereof, and I desire, therefore, that only such limitations shall be placed thereupon as are imposed by. the prior art or as are specifically set forth in the appended claims.

What I claim is:

1. The combination with a marine turbine having ahead and astern sections and a surface condenser to which the sections exhaust, of means for supplying steam to the sections and means for bringing condensate delivered from the surface condenser into heat transfer relation with respect to steam passing through the astern section to limit the temperature of steam exhausted therefrom.

2. The combination with a marine turbine having ahead and astern sections and a condenser to which the sections exhaust, of means for supplying steam to the sections, a spray device for supplying water to steam passing through the astern section to limit the exhaust temperature of such steam, and means for supplying condensate from the condenser to the spray device.

3. The combination with a marine turbine having ahead and astern sections, of. conduits for supplying steam to the sections, a spray device of the astern steam valve is accompanied by operation of the valve in the water conduit.

4. The combination with a marine turbine having ahead and astern sections exhausting to a condenser, of conduits for supplying steam to the ahead and astern sections, a spray device for supplying water to steam passing through the astern section to limit the exhaust temperature of such steam, a conduit for supplying condensate from the condenser to the spray device, valves in the conduits for supplying steam to the astern section and for sup-plying condensate to the spray device, and means for interconnecting the valves so that they may be opened and closed together.

5. The combination with a marine turbine having ahead and astern sections with a common exhaust space therebetween and a condenser in communication with the common exhaust space, of means for supplying steam to the ahead and astern sections, a spray device for injecting water into the exhaust space for the purpose of effecting transfer of heat from steam exhausted from the astern section so as to limit the temperature of such steam, and means for supplying water suitable for boiler feed and at approximately the saturated temperature corresponding to the vacuum to the spray device.

6. In a marine turbine, a casing, a rotor within the casing, ahead and astern blading sections carried by thecasing and the rotor, said sections having their exhaust ends spaced apart to provide a common exhaust space enclosed by the casing, means for condensing steam supplied to the common exhaust space, a circumferential spray device within the casing and disposed so as to be out of the way of steam discharged from the sections for spraying water into steam exhausting from the astern section to limit the temperature of such steam, and means for supplying water suitable for boiler feed and at approximately the saturated temperature corresponding to the vacuum to the spray device.

'7. In a marine turbine installation, a casing, a rotor within the casing, ahead and astern blading sections carried by the casing and by the rotor, means for supplying steam to the ahead and astern sections, a circumferentially extending spray pipe arranged to inject a water spray into steam passing through the astern section, means providing a source of injection water of such temperature that it will not produce undesired chilling of parts of the installation relatively to other parts, and means for supplying water from the source to the spray pipe.

8. In a marine turbine installation, a casing having upper and lower parts, a rotor Within the casing, ahead and astern blading sections carried by the casing and by the rotor, semi-circular spray pipe sections carried by the upper and lower parts of the casing, disposed radially outward of the blading of the sections and arranged to inject a water spray into steam passing through the astern section, means providing a source of water of such temperature that the spray will not produce undesired chilling of parts of the installation relatively to other parts, and means for supplying water from said source to the semi-circular spray pipes.

9. In a marine turbine, a casing, a rotor within the casing, ahead and astern blading sections carried by the casing and by the rotor and having their exhaust ends discharging to a common exhaust space within the casing, means for condensing steam supplied to the exhaust space, a circumferentially extending spray device supported by the casing and disposed radially outward of the blading sections so as to be out of the way of steam exhausted therefrom and arranged to discharge a spray of water into the steam exhausted from the astern section to limit the exhaust temperature of such steam, and means for supplying to the spray device water suitable for boiler feed and at approximately the saturated temperature corresponding to the vacuum.

10. In a marine turbine, a casing having upper and lower parts, a rotor within the casing, ahead and astern blading sections carried by the casing and by the rotor and discharging into a common exhaust space enclosed by the casing, means for condensing steam supplied to the exhaust space, semi-circular spray pipes carried by the upper and lower parts of the casing and disposed adjacent to and radially outward of the discharge end of the ahead section, said semi-circular spray pipes having jets directed toward the discharge end of the astern section so as to supply water to steam exhausting from the astern section in order to limit the temperature of such steam, and means for supplying to the semi-circular spray pipes water suitable for boiler feed and at approximately the saturated temperature corresponding to the vacuum.

WARREN B. FLANDERS.