Gas turbine stator

FIELD: mechanical engineering; gas turbines.

SUBSTANCE: proposed stator of gas turbine has housing with channel to pass gases, ring member arranged around stator housing at a distance in radial direction and functionally coupled with housing, and intermediate members holding ring member at a distance from stator housing in radial direction. Intermediate member are arranged over circumference of ring member at distance from each other and are provided with movable member. Said movable member thrusts against stator housing or ring member with possibility of displacement. At least one of intermediate members features elastic properties in direction of stator radius, and at least one other intermediate member has no such properties.

EFFECT: provision of stator of gas turbine less susceptible to action of thermal expansion of stator housing and ring member functionally coupled with stator housing.

10 cl, 3 dwg

The present invention relates to a stator of a gas turbine, comprising a housing with a channel for passage of gases, an annular element located around the stator at a distance from it in the radial direction and is functionally connected with it, and the intermediate elements, the holding ring element at a distance from the stator in the radial direction. The stator is of a similar design is known from patent US 5215434.

Under the gas turbine in this case means a unit containing at least a gas turbine, compressor, which turns the turbine, and the combustion chamber. Gas turbines are used, such as engines in vehicles and aircraft, as the main ship engines and power plants to drive generators.

Such a gas turbine is usually performed in the form of a turbine of the axial type with one or more turbine stages. The stator of the turbine is located in the channel for the passage of the gas guide vanes. In the description below, the invention is considered gas turbine with the so-called adjustable stator. Under adjustable stator is a stator with adjustable guide vanes that by turning can be set at different angles of inclination to the longitudinal axis of the stator.

To improve the EF is aktivnosti gas turbine gases at the entrance to the first stage of the turbine must have the maximum possible temperature at all possible modes of operation of the turbine. The use of an adjustable stator allows you to change the pressure drop in the previous steps (in the turbine compressor), and thus the temperature of the gases at the turbine inlet of the compressor.

Currently used in gas turbines adjustable stators have a special regulating device, which is designed for adjusting the position of the blades of the stator and rotating them in a different angular position. Such a regulating device usually has a ring element made in the form of a gear ring. The gear ring is rotated relative to the stator housing by means of, for example, hydraulic level. The regulating device also contains a few are made with regard to the form of the ring gear and the toothed ring of the regulatory elements with a toothed wheel which engages with a toothed ring located around the circumference of the toothed ring at a distance from each other. Each such regulatory element is connected with one of the guide blade and rotates with the rotation of the toothed ring. The rotation included in engagement with the toothed ring of the regulatory element is accompanied by rotation of the guide blades and the angle of its inclination.

The possibility of rotation of the toothed ring is provided with internal ring, on which rests the toothed ring. On facing Adelina the direction of the toothed ring surface of the inner ring is usually applied anti-friction coating. The very inner ring rests on the radial fingers still attached to the stator housing.

During operation of the gas turbine stator housing, which is under the direct influence of the hot gases is heated to a higher temperature than the toothed ring. When such a temperature difference of thermal expansion of the stator exceeds thermal expansion of the gear ring. The difference in thermal expansion of the stator housing and the toothed ring is accompanied by a change of their relative position and manifests itself essentially in relative slide mounted on the stator housing of the fingers and the inner ring.

Emerging issues associated with the choice of the optimal size of the clearance between the gear ring and the inner ring. You also need to take into account the danger of asymmetric heating of different parts. Rings due to their asymmetrical heating can purchase an oval shape. Asymmetrical deformation of the ring is accompanied by a change of the gap in the gear mesh and can lead to jamming of the gear ring in his bearing or cause suboptimal increasing the nominal gap in support between the gear and the inner rings.

The present invention was used to develop the stator of the gas round the ins, the construction of which is fully or at least partially solve the problems associated with the different thermal expansion of the stator, in which there is a channel for passage of gases, and an annular element, which is located at a distance from the stator in the radial direction and is functionally connected with the stator housing.

Put in the invention the problem is solved due to the fact that the intermediate elements are arranged on the circumference of the ring element at a distance from each other and contain the movable element, which rests on the stator housing or annular element and is able to move relative to it, at least one of the intermediate elements has in the direction of the radius of the stator elastic properties, and at least one other intermediate element does not possess such properties.

This arrangement and the intermediate element provides stable and accurate mutual movement of the stator housing and covering his ring element. The elastic properties of the intermediate element should allow at least partial compression and expansion respectively decrease or increase the distance between the stator housing and the annular element. With appropriate choice of material and dimensions of this PR is an interstitial element allows you to control the radial direction of the relative movement between the stator and the annular element and at least partially solve the aforementioned problems, generated by changes of the gap in the gear engage and pivot the toothed ring.

In the private embodiment of the invention proposed in the invention, the stator has three intermediate element, which are located on the circumference of the ring element at a distance from each other, at least one of these intermediate elastic elements has the desired properties.

Possessing elastic properties of the intermediate element can contain energy accumulating element, which is preferable to use a spring.

If the movable element, which may be in the form of a roller or wheel rests on the stator housing, the intermediate element may be permanently attached to the ring element, and if the movable element rests on the annular element, the intermediate element may be permanently attached to the stator housing.

Preferably, all of the intermediate elements movable elements are in the form of rollers. In this embodiment, the necessary relative movement of the ring element and the stator, accompanied by the rolling of the rollers intermediate elements, for example, on the surface of the annular element, easily achieved by appropriate choice of the number of intermediate elements and the distance between them.

In another VA who ianthe embodiment of the invention, which is a modification of the previous variant, it is proposed intermediate element is structurally designed in such a way that the casing is unloaded stator is positioned relative to the annular element eccentric and loaded is essentially concentric. This is achieved through, for example, use three stator provided with the said rollers intermediate elements, one of which contains also the above-mentioned spring. The main advantage of this option is the possibility of high-precision alignment of the axes of the annular element and the stator during operation of the turbine.

In a typical performance of the turbine stator contains numerous guides the gas flow vane (nozzle blades)located in the channel for passage of gases, and is intended for adjusting the position of the blades in the channel and turning circle at least from one position to another device that contains installed with the possibility of rotation of the annular element and many installed rotatably regulatory elements, which are located on the circumference of the ring element at a distance from each other, each of which is connected with one of the vanes and which are in contact with the annular element and have the opportunity of rotation during the rotation of the ring e is of amenta, turning thereby guide vanes from one position to another. In this case, the annular element and the regulatory elements can be properly executed and are in engagement toothed sections, through which the rotation of the vanes.

Below the invention is described in more detail on the example of one of the variants of its implementation with reference to the accompanying drawings on which is shown:

figure 1 - schematic representation in section of a stator made in accordance with the preferred option

figure 2 - schematic representation in front view of the stator in accordance with the preferred option, in two positions, and

figure 3 - the mechanism of regulation of stator blades.

1 schematically shown in the cross section of the stator 1 of a gas turbine. The stator 1 of a gas turbine has a housing 2 with channel 3 for passage of gases in the direction shown in the drawing by arrows 16. In the passage of gases are also shown in figure 3 blades 4 of the stator, directing the stream flowing through the stator gases.

The stator 1 has a device 5, which is intended to regulate the angular position of the blades 4 of the stator. The regulating device 5 includes a ring element 6 made in the form of a gear ring. For simplicity, in further part of the Scriptures instead of the term "annular element 6" is used the term "toothed ring 6". The toothed ring 6 covers the outside of the housing 2 of the stator and located at a distance from it in the radial direction. The toothed ring 6 is connected with a hydraulic servocylinder (not shown) and can rotate relative to the stationary housing of the stator.

The regulating device 5 also contains several regulatory elements 7 with the gear wheels, the shape of which conforms to the shape of the ring gear and the toothed ring 6. Each regulatory element 7 is connected with one of the guide vanes 4 of the stator. Regulatory elements 7 are located at a distance from each other around the circumference of the toothed ring 6 and are in engagement with its teeth. Located in engagement with the toothed ring 6 regulatory elements 7 are rotated by turning the toothed ring 6 and turn the blades 4 of the stator from one angular position to another.

Case 2 stator has a circular projecting flange 8. In the preferred embodiment, this flange 8 is made as a separate part that bolts 9 is fixed to the body 2 of the stator.

The flange 8 has three protruding in the radial direction of the element 10, 11, 12, which determine the distance between the body 2 of the stator and the toothed ring 6 (see figure 2). Intermediate elements 10-12 evenly spaced around the circumference of the stator at equal angular distance is t friend. Each intermediate element 10-12 has a roller 13, which rests against a radially internal surface of the toothed ring 6 and can roll on it. The first intermediate element 10 contains, in addition, the energy accumulating element 14 made in this case in the form of springs. Energy accumulating element 14 of the first intermediate element 10 mounted on the lever 15, which communicates with the pressed against the toothed ring movable roller 13. The lever 15 with a spring and a roller pivotally mounted on the flange 8 of the stator housing and is rotatable with respect to it.

When the flow through located in the housing 2 of the stator channel flow of hot gases to the stator housing is heated and expands. Not heated by the gases of the body 2 of the stator is cooled, and its size accordingly. Occur when heating and cooling thermal deformation under the direct influence of the hot gas housing 2 of the stator more than thermal deformation of the toothed ring. Compensation of the difference of thermal expansion of the stator housing and the toothed ring is proposed in the invention design, due to the precompression of the spring 14, which presses the rollers 13 to the inner surface of the toothed ring 6 and when running and at idle the turbine. In figure 2 the position of the flange 8 when the slave is melting the turbine shown in dotted lines, and at idle the turbine - solid lines. As of the spring 14, it is preferable to use a package of Cup springs, which create a force directed along the radius of the stator. The proposed invention the stator when the load axis of the toothed ring 6 coincides with the axis of the housing 2 of the stator, and in the absence of load - did not match and offset from it by some distance.

The ability to easily control the position of the toothed ring 6 relative to the body of the stator is provided in the proposed in the invention of a structure by determining the eccentricity of a gear ring when heated to high temperatures of the stator and the subsequent change in the position of the rollers 13 by using, for example, the corresponding Cam (not shown).

Figure 3 shows a device 5 that is designed to control the pitch angle of the blades 4 of the stator. Figure 3 shows, in particular, the toothed ring 6, one of the regulatory elements 7 with the toothed wheel, the shape of which conforms to the shape of the ring gear and the toothed ring 6, and one of the blades 4 of the stator, which is connected with a regulating element 7.

Under the elasticity of the intermediate element in this case is understood as the possibility of energy accumulating element elastically deformed when increasing the applied compression force of and accept, and the initial shape by reducing the compression force of up to the initial level.

Used in the description of the term "circumference" refers to lying in the same plane as the inner or outer edge of the respective parts. In this sense, the use of this term is not limited to parts having a circular shape.

The above-described first intermediate element 10 has the elastic properties in the direction of the radius of the stator 1. It is said, however, does not mean that the first intermediate element 10 has the elastic properties only in the direction of the radius of the stator 1, and he may have the appropriate elastic properties in other directions.

Proposed in the invention the stator structure can be realized in single-shaft and twin-shaft gas turbines. Single-shaft gas turbine compressor(s) is connected(s) with a drive shaft of the turbine, which is connected with the output shaft. In such turbines the combustion chamber is located between the compressor(s) and drive the turbine. In the two-shaft gas turbine compressor(s) is connected(s) shaft with the turbine compressor. While driving the turbine is not mechanically connected to the turbine of the compressor, and is located in the direction of flow of gases behind the turbine compressor and is connected to the output shaft. The combustion chamber in such turbines is located between the compressor and turbine and compressor.

In the above-described variant of the design of the stator of the gas that is Bina, which should only be considered as a preferred example of a possible implementation of the invention may be made of various changes and improvements without the need to go beyond the scope of the following claims.

Thus, in particular, instead of a pack of Belleville springs as energy accumulating element in another embodiment, it is possible to use a twisted spring. Twisted the spring can be mounted so that its Central axis was located essentially in the direction of the radius of the stator. Twisted spring can also be set differently, for example, so that its Central axis was located essentially along the axis of the stator. In this case, the intermediate element must be connected with a spring part, which could be moved in the axial direction. This item must be associated with a toothed ring so that relative radial movement of the toothed ring and the stator housing in the intermediate element appeared passed this part of the elastic force directed along the Central axis of the spring.

Energy accumulating element can also be performed in the form of a cylinder such as a pneumatic cylinder, in which the function of the elastic element performs the working environment (air). In another embodiment, as accumulating EN is the rgiya item, you can use the item, made of elastic material such as rubber. In this case, the elastic properties of the intermediate element will be determined by the internal structure of an elastic material, and not a form of energy accumulating element.

As the rolling element instead of the above-described roller in the proposed invention the intermediate element, you can use the element sliding on the surface of the toothed ring 6. Structurally, such an element can be done in the form of, for example, a curved beam with a corresponding cross section.

Above the flange 8, which is a separate part that is attached to the stator housing by respective bolts 9 can be replaced by a flange, made in one piece with the rest of the stator housing.

To control the pitch angle of the blades of the stator on the regulatory elements instead of gears included in engagement with the annular element, you can use rollers, obkatyvalisj on the inner surface of the annular element. In another embodiment, for this purpose, you can use the groove or grooves made on the annular element. Such groove or grooves can be performed, for example, on the radially outer surface of the annular element at a certain circumference distance from each other. Made in the annular element grooves d which must be stretched in the direction perpendicular to the main plane of the ring element. Regulatory element in this case is a lever, one end of which is connected with a rotary blade of the stator, and the other is in the groove of the annular element. On the outer end of the lever can be fastened part spherical shape, in particular a ball which enters the grooves of the ring element. The rotation of the blades of the stator at a particular angle is in this case by turning the ring element at the appropriate angle.

In the proposed invention the stator, in contrast to the above options, in which the spring has only one intermediate element, the spring may have one or more intermediate elements. Sometimes, for example, for mounting on the stator housing ring element of the mechanism of rotation of the blades use four intermediate element. In this case, two intermediate element must have the appropriate spring. Intermediate elements in that the stator should be located so that the total force generated by springs, was directed in the same direction, and a stator with three intermediate elements, only one of which has a corresponding spring.

The above description, which considered the construction of a stator of a gas turbine with different thermal model is m the toothed ring and the stator, does not limit all possibilities of practical implementation of the invention, which may find application in other areas of technology that uses a ring element functionally associated with the stator housing.

1. The stator (1) of a gas turbine, comprising a housing (2) with the channel (3) for passage of gases, the ring element (6)located around the stator at a distance from it in the radial direction and is functionally connected with it, and the intermediate elements (10, 11, 12), retaining ring element at a distance from the stator in the radial direction, characterized in that the intermediate elements (10, 11, 12) are arranged on the circumference of the ring element (6) at a distance from each other and contain the movable element (13)which abuts on the housing (2) of the stator or in the annular element (6) and has the ability to move with respect to it, and at least one (10) of the intermediate element has in the direction of the radius of the stator elastic properties, and at least one other intermediate element (11, 12) does not possess such properties.

2. The stator according to claim 1, characterized in that it contains three intermediate element (10, 11, 12), which are located on the circumference of the ring element (6) at a distance from each other, at least one (10) of these intermediate elements has at the other properties.

3. The stator according to claim 1 or 2, characterized in that possessing elastic properties of the intermediate element (10) contains the energy accumulating element (14).

4. The stator according to claim 3, characterized in that the energy accumulating element (14) made in the form of a spring.

5. The stator according to any one of the preceding paragraphs, characterized in that the movable element (13) is designed as a roller or wheel.

6. The stator according to claim 5, characterized in that the intermediate element (10, 11, 12) is rigidly attached to the ring element (6), if the movable element (13) rests on the housing (2) of the stator or the housing (2) of the stator, if the movable element (13) abuts against the annular element (6).

7. The stator according to any one of the preceding paragraphs, characterized in that the intermediate element (10, 11, 12) is located so that the housing (2) unloaded stator is positioned relative to the annular element eccentric and loaded is essentially concentric.

8. The stator according to any one of the preceding paragraphs, characterized in that it contains numerous guides the gas flow blades (4)located in the channel for passage of gases, and is intended for adjusting the position of the blades in the channel and turning circle at least from one position to another device (5), which contains installed with the possibility of rotation of the ring element (6) and many installed with the capability, the capacity of rotation of the regulating elements (7), located on the circumference of the ring element at a distance from each other, each of which is connected with one of the guide blades (4) and which are in contact with the annular element and have the opportunity of rotation during the rotation of the ring element, thereby turning vanes (4) from one position to another.

9. The stator of claim 8, characterized in that the annular element (6) and regulatory elements (7) are properly executed and are in engagement toothed sections, through which the rotation of the vanes.

10. The stator according to any one of the preceding paragraphs, characterized in that the gas turbine is designed for driving a vehicle.