US783153A - Packing and means for taking up thrust in turbines. - Google Patents

Description

No. 783,153. PATENTED FEB. 21, 1905.

Q J. STUMPF.

PACKING AND MEANS FOR TAKING UP THEUST IN TURBINES.

APPLICATION FILED D30. 7, 1904.

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Patented February 21, 1905.

UNITED STATES PATENT OEEIcE.

JOHANN STUMPF, OF CHARLOTTENBURG, NEAR BERLIN, GERMANY, ASSIGN OR TO GENERAL ELECTRIC COMPANY, A CORPORATION OF NEW YORK.

PACKING AND MEANS FOR TAKING UP THRUST IN TURBINES.

SPECIFICATION forming part of Letters Patent No. 783,153, dated February 21, 1905.

Application filed December 7, 1904. Serial No. 235,787-

T0 all whmn it may concern:

Be it known that I, J OHANN STUMPF, a subject of the King of Prussia, German Emperor, and a resident of 28 Rankestrasse, Charlottenburg, near Berlin, Kingdom of Prussia, German Empire, have invented certain new and useful Improvements in Packing and Means for Taking up End Thrust in Elastic-Fluid Turbines, of Which the following is a specification.

In the operation of certain types of elasticfiuid turbines a considerable end thrust is produced that may be due to the manner in which motive fluid is supplied to the bucket-wheels, the shape of the buckets themselves, or to the machines or mechanisms driven by the turbine. The latter is particularly true where the turbines are employed to drive boat-screws or to drive hoisting apparatus through wormgearing. In order to maintain the efficiency of a multistage elastic-fluid turbine, it is necessary to provide packing between adjacent stages to prevent leakage. These packings are difficult to maintain, as experience has shown, owing principally to the high surface speed of the shaft or other part engaging the packings.

The present invention has for its object to combine in a single structure means for taking up the end thrust and packings for preventing leakage between stages.

In carrying out the invention the turbine is divided into the desired number of stages, each stage containing, in addition to the wheel buckets and fluid-discharging device or devices, one or more disks secured to the wheelshaft. I may place one of these disks in each stage or a less number, if desired. Situated adjacent to these disks are partitions or walls, which divide the easing into stages. These partitions should be strong enough to sustain the pressure exerted upon them by the disk,

as will hereinafter appear, without undue bending. Between each disk and the adjacent partition is formed one or more chambers, which are preferably concentric with the shaft. All of these chambers are provided with inlet-passages, and said passages may be connected to a common or to separate sources of fluid-supply under pressure. The disks and partitions when the turbine is in operation are separated by a thin film of liquid under a pressure more or less great. I may use oil to hold the surfaces out of contact where the condensed steam is not returned to the boiler, or I may use water, in which case the objection to oil is avoided. The pressure of the fluid between the surfaces can be regulated by valves or other means; but it should be great enough to cause a gradual flow and to maintain a thin film at all times. By maintaining a pressure great enough to force liquid into the several stages against the pressure thereof or by maintaining a pressure equal to that of the stage it is evident that the transfer of motive fluid from one stage to the next is prevented. It also follows that since there is a capillary layer or film of liquid between adjacent surfaces of the disk and partition the two may move toward and away from each other to a slight extent under shock and vibration without injury to the turbine as a whole and the seal between stages will remain intact. Since the stages work at different pressures, it is preferable to decrease the pressure of the liquid supplied to the several chambers in the same ratio. If a single source of liquid-supply is employed, reducing-valves or bafilcrs can be employed for this purpose with advantage.

I may use my improved packing and endthrust device between each stage, or I may use it between a less number, depending upon the conditions for which the turbine is intended.

In the accompanying drawing is shown an embodiment of the invention applied to a multistage turbine.

1 represents the casing of the turbine, which may be divided into parts on an axial plane, as indicated by the dotted line, or it may be divided in any other suitable way. The casing is divided by partitions 2 into stages, each of which is provided with a bucket-wheel 3, having one or more rows ofbuckcts 4. Steam or other elastic fluid is supplied to the buckets by nozzles 5, the noz- Zles receiving fluid from the chambers 6. For the sake of simplicity the means for supplying steam to the chambers is omitted and also the conduits for transmitting steam from one stage to the other. The wheels are mounted on the shaft 7, which is supported in suitable bearings. Each partition is provided with a hub-like projection 8, containing a chamber 9, that is concentric with the shaft. Fluid is admitted to each chamber by a conduit 10, which in turn is connected to a supply-pipe 11. The conduits pass through the casing at any suitable point and are provided with packings to prevent leakage. When a single source of fluid under pressure is employed, I may use reducing-valves or baffling devices between the pipe 11 and the several conduits. Mounted on the shaft and situated adjacent to the projections 8 on the partitions are disks 12, which may be cored or turned out to form part of the chamber 9. The particular formation of the projections, chambers, and disks is immaterial.

The turbine may be provided with a number of stages; but the invention is also applicable to single-stage turbines. It is not necessary to provide each stage with a pressure-disk 12; but it is desirable to do so. Where such disks and fluid-supply conduits are provided, they form a seal to prevent the leakage of steam or other elastic fluid from one stage to the next and also serve to transfer the end thrust from the shaft to the partitions and wheelcasing. If a lengthwise thrust is produced on the shaft in the direction of the arrow, it is transmitted through the several disks 12 to the projections on the partitions. When liquid under pressure is admitted to the chambers 9, it flows out between the adjacent surfaces in the form of a thin film, and the pressure should be great enough to prevent the motive fluid in each stage from leaking between these surfaces into the adjacent stage. VVhere'there is no longitudinal thrust on the shaft due to the bucket action, but there is a thrust due to the character of the apparatus driven thereby, the disk 12 and cooperating parts will function in the same manner.

It is obvious that the arrangement can be altered to meet the desired conditions, also that the packings in the different stages can be oppositely disposed, if desired. Instead of making the disks 12 separate they can, if desired, be formed directly on the wheels, in which case the longitudinal dimension of the turbine will be somewhat reduced. The packing arrangement can also be used on a turbine where there is no end thrust. My invention is also applicable to multistage turbines wherein the casings are divided into separate sections and the sections provided with independent shafts.

In accordance with the provisions of the patent statutes I have described the principle 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. 7

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

1. In an elastic-fluid turbine, the combination of'a casing, relatively movable elements for producing motion contained therein, a shaft, and a fluid packing means for preventing the passage offluid out of the casing which also serves to transfer the end thrust on the shaft to the casing.

2. In an elastic-fluid turbine, the combination of a casing, relatively movable elements contained therein, a shaft, relatively movable parts in juxtaposition, and means for supplying liquid thereto under pressure to prevent leakage of motive fluid and also to transfer the end thrust on the shaft to the casing.

3. In an elastic-fluid turbine, the combination of a casing, partitions for dividing the easing into compartments, relatively movable elements in the compartments for producing motion, a shaft, and means cooperating with the partitions to prevent leakageand also to transfer the end thrust on the shaft to the partitions.

4:. In an elastic-fluid turbine, the combina tion of a casing, partitions for dividing the easing into compartments, a shaft, bucketwheels mounted on the shaft and located in the compartments, disks also mounted on the shaft and cooperating with the partitions,- and conduits for discharging fluid between the partitions and the disks to prevent leakage and also to transfer the end thrust on the shaft to the partitions.

5. In an elastic-fluid turbine, the combina tion of a casing, partitions for dividing the casing into stages, a shaft located in thestages or compartments, bucket-Wheels on the shaft, and fluid packing devices for two or more of the stages which discharge into the wheelcompartments."

6. In an elastic-fluid turbine operating by stage expansion, the combination of bucketwheels, a shaft, devices for discharging fluid to the wheels, fluid-packing devicesfor preventing the leakage of motive fluid from one compartment to another and also receive the end thrust of the shaft, and a means for simultaneously feeding the packing devices with fluid under pressure.

7 In an elastic-fluid turbine operating by stage expansion, a casing, a plurality of partitions for dividing the easing into compartments, bucket-wheels, a shaft, devices for discharging motive fluid to the wheels, fluidpacking devices onsaid partitions for preventing the leakage of motive fluid from one com- IIO partment to another, and unitary means for simultaneously feeding said packing devices With fluid under pressure.

8. In an elastic-fluid turbine, the combination of a casing, partitions for dividing said casing into compartments, relatively movable elements in the compartments for producing motion, a shaft extending through said partitions, and fluid-pressure packing means arranged betWeena partition and the shaft and 10 having bearing-surfaces in a plane at right angles to said shaft.

In Witness whereof I have hereunto set my hand this 12th day of October, 1904:.

J OHANN STUMPF. Witnesses:

HENRY HAsPER, MAX HAMBURGER.

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