US2082601A - Turbine arrangement - Google Patents

Description

June 1, 1937. R. G. STANDERWICK TURBINE ARRANGEMENT Filed March 50, 1935 a m 2M T ws 7/4/23 M 2 4 1 Ill Z Ihvehbor": Reginald G- Standerwick,

y P-Ms Attovhe Patented June 1, 1937 UNITED STATES TURBINE ARRANGEMENT Reginald G. Standerwick, Marblehead, Mass, assignor to General Electric Company, a corporation of New York Application March 30, 1935, Serial No. 13,900

4 Claims.

The present invention relates to extraction and mixed pressure turbine arrangements, that is, to multi-stage turbines having a conduit connected to an intermediate stage for extracting elastic fluid from or conducting elastic fluid to such intermediate stage. More specifically, the invention relates to the type of these turbine arrangements in which it is desired to control the pressure at the intermediate stage, preferably to maintain this pressure constant.

The pressure control usually is effected by means including a valve, such as a grid type ring valve, disposed behind the intermediate stage as regards the direction of fiow and a control mechal5 nism connected to the valve.

The object of my invention is to provide an improved construction and arrangement of the type of turbine arrangements above specified whereby certain elements of the control mechanism are simplified, leakage from such element is reduced,

and accurate control is assured.

For a consideration of What I believe to be novel and my invention, attention is directed to the following description and the claims appended thereto in connection with the accompanying drawing.

In the drawing, Fig. 1 illustrates a sectional view of a turbine arrangement embodying my invention, and Fig. 2 is a sectional view along line 2-2 of Fig. 1.

The arrangement comprises a multi-stage turbine having an outer casing It) with a flanged opening H and a conduit l2 connected thereto. The conduit l2 serves for conducting elastic fluid extracted from or supplied to an intermediate stage of the turbine. A grid type valve is provided at the intermediate stage to control the pressure therein. The valve includes a stationary member l2a with radial slots l3 therein and a rotatable member M with radial slots it therein. The rotatable member Hi consists of two halves secured together by bolts l6 and is supported on the stationary member and rotates concentrically with turbine shaft l1. The slots Ill are 5 Wider than the slots 53 and arranged so that during rotation the slots l5 first register with a few of the slots I3 and during further rotation register with more and finally with all of the slots l3. In one end position a minimum area for 50 conducting fluid from one stage to the other is obtained and in the other end position a maximum area of flow is established. The opening 1 area determines the flow from the extraction stage to the succeeding stage and consequently .also the pressure in the extraction stage.

Themechanism so far described is typical of grid-controlled extraction and mixed pressure turbines. The hydraulic mechanism for controlling the position of the grid valve, more specifically the movable member 14, hydraulic motor l8 and a pilot valve is, which latter is controlled by a governor 20, in the present instance a pressure-responsive device connected to the conduit l2. The pilot valve is connected to the hydraulic motor by a follow-up mechanism, as will be more fully described hereinafter.

In accordance with my invention, as shown in the drawing, the hydraulic motor 18 and the pilot valve iii are disposed on opposite sides of the turbine. The hydraulic motor includes a cylinder 2i which has a flanged portion or projection 22 secured to afianged opening 23 of the turbine casing [0. The flanged portion 22 forms achamber or opening into which a radial projection or projections 23 of the member l4 extends. To permit access to the projection 24, a detachable plate 25 is secured to portion 22 of the cylinder. A piston 26 is slidably disposed within the cylinder 2| and connected to the projections 24 of the grid valve by a stem 2'! and members 28 held on a guide block 28a and disposed between the projections 24. A packing sleeve 29, preferably a long bronze gland, is provided to reduce leakage from the cylinder 2| along the piston rod 2'1.

The pilot valve is of known design, comprising a.-

casing 30, secured to a plate 30a which forms an integral part of the portion 22, and a valve stem 3| having heads 32 normally registering with ports in the casing. These ports are connected by conduits 33 and the right-hand side respectively of the horizontally disposed hydraulic cylinder 2|. Oil or like actuating fluid such as steam is conducted to the pilot valve by a conduit 35 and discharged therefrom by conduits pilot valve stem 3| is connected to an intermediate point of a floating lever 38, whose left-hand end is connected through a rod 39 to the governor 20. The latter may include a pressureresponsive device connected to the conduit l2. The right-hand end of the lever 38 carries a roller 38a which bears against a cone 40 secured to a stem ll. The latter is connected to the grid valve and forms in substance an extension of the piston stem 2'! of the hydraulic motor l8.

During operation, actuation of the governor which may be due to a change in pressure in the intermediate stage causes upward or downward movement of the pilot valve stem 3i which in known manner causes displacement of oil or like includes a 34 to the left-hand side.and

36 and 31 respectively. The,

70 sealed by actuating fluid in the hydraulic motor. For example, if the pilot valve moves downward it permits the supply of fluid from the conduit 35 through the pilot valve casing and the conduit 5 34 to the right-hand side of the piston 26, and the discharge of fluid from the left-hand side of the piston 26 through the conduit 33, the pilot valve casing and the discharge conduit 36. The piston 26 thereby is moved towards the left, ef-

fecting closing of the grid valve. Movement of the piston 26 also causes restoring of the pilot valve position. In -the aforementioned example movement of the piston 26 towards the left causes similar movement of the cone 40 whereby the roller 38a with the right-hand end of the floating lever 38 is moved upward until the pilot valve heads 32 again cover the ports connected to the conduits 33 and 34.

It will be noted that the hydraulic cylinder of my arrangement needs one packing only, namely, the packing sleeve 29 surrounding the stem 21, because the stem 21 projects through one end only of the cylinder 2!, whereas the other end of the cylinder is completely closed by a 25 cover 42. This reduces leakage and, as will be noted, any leakage which might occur will take place along the sleeve 29 and fluid leaking along the stem 29 from the left-hand end of the cylinder 2| flows into the interior of the turbine. The

30 arrangement is especially advantageous when high pressure steam is used as an actuating fluid for the hydraulic motor because in this case leakage steam flowing along the sleeve 29 into the turbine is absolutely harmless in the latter.

The extension 4| of the stem 21, which extension carries the cone 40, is sealed by means including a packing 43 and a plug 44 for retaining the packing 43 in position. The packing 43 is relatively short because it has to seal against the low intermediate stage pressure only, where- 'as the long packing 29 has to seal against the high pressure in the cylinder 2|.

Another distinct advantage of my arrangement is the provision of the cone 46 which is round in cross-section so that slight rotational movement of the piston 26 together with the stem 21 and its extension 4|, causing rotational movement of the cone 40 about its axis, does not aifect the restoring action and the control of the tur- 50 bine.

A further advantage of the arrangement is that the provision of the pilot valve and the hydraulic motor on opposite sides of the turbine casing reduces considerably the overall projection of the turbine arrangement.

Looking at my invention from another viewpoint, the arrangement comprises a turbine casing 16 with an open flanged portion 23 through which a projection 24 of the movable grid valve member extends. The open portion 23 is closed by a member 22, which latter may be annular 'or of any desirable shape, and a cover plate 25. The hydraulic mechanism for positioning the grid valve comprises a motor which has a cylinder 2| horizontally disposed on one side of the turbine and integrally united with the member 22. A piston 26 in the cylinder is connected to the ring valve by a stem 21. The latter projects through an opening in the member 22 and is a long sleeve, such as a bronze gland '29, to reduce leakage of fluid along the stem 27.

The stem 21 has a projection 4i extending through the opposite side of the member 22 and carrying at its free end a restoring cone 46. The

1 75 cone 46 is preferably rounded in cross-section but it may also comprise a surface of revolution of a special contour to permit compensation for irregularities in the flow travel characteristics of the grid valve. A pilot valve for controlling the flow of actuating fluid to the motor, which fluid may be high pressure steam, has a casing 36 secured to a projection 30a of the member 22. The follow-up mechanism between the pilot valve and the hydraulic motor includes the aforementioned cone 40 and a lever 38 having one point pivotally connected to the pilot valve stem and another point carrying a roller 38a bearing against the cone 40.

Having described the method of operation of my invention, together with the apparatus which I now consider to represent the best embodiment thereof, I desire to have it understood that the apparatus shown is only illustrative and that the invention may be carried out by other means.

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

l. A multi-stage elastic fluid turbine arrangement including a turbine casing with a conduit connected to an intermediate stage through which conduit elastic fluid is extracted from or supplied to the turbine, valve means connected to the turbine for controlling the flow of fluid through the intermediate stage, and means for positioning the valve means comprising a hydraulic motor disposed on one side of the turbine and a pilot valve disposed at right angle to the motor on the other side of the turbine, the motor having a piston with a stem connected to the valve means, means for moving the pilot valve, and means for restoring the pilot valve comprising a stem connected to the valve means and forming an extension of the piston stem.

2. A multi-stage elastic fluid turbine arrangement including a turbine casing having an opening, valve means in the casing for controlling the flow of elastic fluid between two consecutive turbine stages, said valve means having a projection extending through the opening, and a control mechanism for the valve means comprising a hydraulic motor disposed on one side of the turbine, a pilot valve disposed on the opposite side of the turbine for controlling the motor, and a governor for moving the pilot valve, the motor including a horizontally disposed cylinder with a portion having an opening registering with the opening of the casing and forming a chamber for said projection, a stem having an intermediate point connected to the projection, a piston in the cylinder secured to one end of the stem, a cone secured to the other end of the stem and a lever connected to the pilot valve and engaging the cone to effect restoring of the pilot valve in response to movement of the moto 3. A multi-stage turbine arrangement including a turbine casing having a flanged opening, valve means in the casing for controlling the flow of fluid between two consecutive turbine stages, said valve means having a projection extending through the flanged opening, means for closing the opening including a member engaging the flanged opening, and hydraulic control means for positioning the valve comprising a horizontally disposed cylinder having a casing integrally formed with the closing member, a piston in the cylinder, a stem secured to the piston and projecting through one side of the closing member and through the opposite side of the closing member, an intermediate point of the piston stem being connected to said projection and means including a vertically disposed pilot valve connected to the free end of the jecting through one side of the closing member piston stem and a governor connected to the and through the opposite side of the closing pilot valve for controlling the flow of an actuatmember, an intermediate point of the piston stem ing fluid to the cylinder. being connected to said projection and means 5 4. A multi-stage turbine arrangement includincluding a vertically disposed pilot valve con- 5 ing a turbine casing having a flanged opening, nected to the free end of the piston stem and a valve means in the casing for controlling the governor connected to the pilot valve for conflow of fluid between two consecutive turbine trolling the flow of an actuating fluid to the cylstages, said valve means having a projection exinder, the connection between the pilot valve 10 closing the opening including a member engagscrewed onto the free end of the stem, said cone ing the flanged opening, and hydraulic: control having a special contour to permit compensation means for positioning the valve comprising a for irregularities in the flow travel characterishorizontally disposed cylinder having a casing tics of the grid valve. 15 secured to the closing member, a piston in the l5 cylinder, a stem secured to the piston and pro- REGINALD G. STANDERWICK.

tending through the flanged opening, means for and the stem including an adjustable cone 10

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