RU2369746C1 - Gas turbine engine rotor - Google Patents

Abstract

FIELD: engines and pumps.

SUBSTANCE: gas turbine rotor comprises disks of the fist and second stages, one of them being splined onto turbine rotor shaft, and front and rear intermediate disks fitted in interdisk chamber. First stage disk has L-like flange coupled with that of the second stage disk with the help of studs and nuts. First stage disk flange has flexible element, tapered inner surface and circular rib to lock axially rear intermediate disk hub along outer surface. Second stage disk flange comprises multiple radial openings located opposite against each flange joint and having cross section with antiparallelogram rounded-angle shape, larger base being located on the nut side.

EFFECT: higher reliability, ease of manufacture and assembly.

6 dwg

Description

The invention relates to designs of rotors of turbines of aircraft gas turbine engines.

A turbine rotor of a gas turbine engine is known, in which the disk of the last stage is fixed on the radial flange of the shaft by a bolt joint, and the remaining disks are axially fixed by a coupling bolt (RF Patent No. 2263809, F02C 7/28, 2008). The disadvantage of this design is the inability to place an additional shaft, for example, a low-pressure turbine rotor shaft, inside the turbine rotor.

Closest to the claimed one is the design of the turbine rotor of a gas turbine engine, in which the first-stage disk is fixed on the radial shaft flange with axial bolts, the second-stage disk is fixed axially on the shaft flange with a nut and in the circumferential direction by axial pins, and the hubs of the front and rear intermediate disks fixed on the shaft by annular flanges (RF Patent No. 2232901, F01D 5/02, 2004).

The disadvantages of the known design are the lack of reliability and manufacturability during assembly due to the low strength of the disks of the first and second stages, the width of the hubs of which is limited by the radial flange of the shaft and the fastening elements of the disks to it, as well as ring flanges for fixing the intermediate disks.

The technical problem to which the present invention is directed is to increase the reliability and manufacturability of the turbine rotor of a gas turbine engine by increasing the strength of the disks of the first and second stages of the rotor and facilitating the assembly process.

The essence of the invention lies in the fact that in the rotor of a turbine of a gas turbine engine with disks of the first and second stages and front and rear intermediate disks installed in the interdisc cavity, according to the claims, the first stage disk is made with an L-shaped flange, the second stage disk flange is made with an elastic element , conical inner surface and on the outer surface with an annular rib of axial fixation of the hub of the rear intermediate disk. The connection of the flanges of the disks of the first and second stages is carried out using axial studs and nuts, while the flange of the disk of the second stage includes a plurality of radial windows located opposite each connection, the cross section of which has the shape of an isosceles trapezoid with rounded corners and a wide base on the side of the nuts. One of the disks is mounted on the shaft of the turbine rotor with a spline connection.

Since the disk of the first stage is loaded with smaller centrifugal forces compared to the disk of the second stage due to the lower mass of the first working blade compared to the second working blade, the axial width of the hub of the disk of the first stage allows the flange of its attachment to the second stage disk to be L-shaped. This embodiment provides high-quality tightening of the nuts on the studs from the side of the disk of the first stage when assembling the turbine rotor, which increases the reliability of the turbine rotor.

The implementation of the flange of the disk of the second stage with an elastic element between the flange itself and the hub of the disk allows, due to the deformation of the elastic element, to reduce the stress in the flange at various temperature radial movements of the hub and flange.

Since, for technological reasons, it is impossible to manufacture a second-stage disk with an L-shaped flange similarly to a first-stage disk, the second-stage disk flange is made with radial windows in which the fastening nuts of the second-stage disk flange are located. In this case, the cross section of the windows has the shape of an isosceles trapezoid with rounded corners and a wide base on the side of the nuts.

This embodiment of the windows located opposite each flange connection allows you to make jumpers between the windows with equal strength along the length and place the number of nuts with studs necessary for reliable mounting of the disk. At the same time, it is possible to screw nuts through windows, which in cross sections repeat the contours of the nuts, facilitating the assembly process.

The implementation of the flange of the disk of the second stage on the outer surface with an annular rib of axial fixation of the hub of the rear intermediate disk eliminates the vibration of the front and rear intermediate disks, which increases the reliability of the turbine rotor. The conical inner surface allows the second stage disc to be made with a maximum axial hub width, increasing the strength of the disc and the reliability of the turbine rotor.

The connection of the flanges of the disks of the first and second stages with the help of axial studs with nuts allows a reliable connection of the turbine rotor disks with a minimum axial distance between the hubs of the disks equal to the axial dimension of the nut, thereby increasing the reliability of the turbine rotor due to the hardening of the disks.

Fixing one of the disks with a splined connection on the shaft of the turbine rotor allows reliable transmission of torque from both disks to the specified shaft.

The inventive device is illustrated by the following figures.

Figure 1 shows a longitudinal section of a rotor of a turbine of a gas turbine engine.

Figure 2 shows the element I in figure 1 in an enlarged view, and in figure 3 - section aa in figure 2.

Figure 4 shows a section bB in figure 2, and in figure 5 is a view In figure 2.

6 is a design view of a turbine rotor with a first-stage disc mounted on a turbine rotor shaft.

The rotor 1 of the turbine of a gas turbine engine consists of a disk of the first stage 2 and a disk of the second stage 3, in the interdisc cavity 4 between which are installed the front 5 and rear 6 intermediate disks.

Disks 2 and 3 are interconnected by a flange connection 7 with axial studs 8 and nuts 9 and 10 at opposite ends of the studs. The flange 11 of the disk of the first stage 2 is made L-shaped in cross section, providing an “approach” to the nuts 9 of the fastening of the disk 2 when assembling the turbine rotor 1.

The flange 12 of the disk of the second stage 3 is made on the outer surface 13 with an annular radial rib 14 for axial fixing of the hub 15 of the rear intermediate disk 6.

The flange 12 is made with a conical inner surface 16 and an elastic element 17 between the flange 12 itself and the hub 18 of the disk of the second stage 3.

To accommodate the nuts 10 for securing the disk of the second stage 3 in the flange 12, radial windows 19 are made, the cross section of which is in the form of an isosceles trapezoid with rounded corners, and the base of the trapezoid 20 is made from the side of the nut 10, which makes it possible to make jumpers 21 of the flange 12 between the windows 19 equally strong for the circumferential force acting on the disk of the second stage 3. The number of windows 19 is equal to the number of nuts 10, which allows the jumpers 21 to be equally strong.

On the outside of the window 19 is closed by the hub 15 of the rear intermediate disk 6, which eliminates the penetration of the nut 10 into the peripheral part of the interdisc cavity 4 in the event of a failure of the stud 8, which in turn significantly reduces the imbalance of the turbine rotor 1 when the stud 8 is broken.

To transmit torque to the shaft 22, one of the disks of the rotor 1, for example, the disk of the second stage 3, is installed by a spline connection 23 on the shaft 22.

The work is as follows.

When assembling the rotor 1, the pins 8 are installed in the disk of the second stage 3, on which the nuts 10 are screwed through the windows 19. Next, the front and rear intermediate disks 5 and 6 are installed in the rotor 1, as well as the disk of the first stage 2, which is fixed with a L-shaped the flange 11 with nuts 9. The disks 2 and 3 thus assembled are mounted using a spline connection 23 on the shaft 22 of the turbine rotor 1.

In the case of installing the second-stage disk 3 with a spline connection 23 on the shaft 22 during the operation of the rotor 1, the peripheral force from the first-stage disk 2 through the flange connection 7 and the axial studs 8 is transmitted to the second-stage disk 3 and then through the spline connection 23 to the shaft 22. The flange connection 7 with studs 8 and nuts 9 and 10 provides a reliable connection of discs 2 and 3.

Claims (1)

A turbine rotor of a gas turbine engine with first and second stage disks and front and rear intermediate disks installed in the inter-disk cavity, characterized in that the first stage disk is made with an L-shaped flange, the second stage disk flange is made with an elastic element, a conical inner surface and, according to the outer surface, with an annular rib of axial fixation of the hub of the rear intermediate disk, and the connection of the flanges of the disks of the first and second stages is carried out using axial studs and nuts, while the disk flange The first step includes a plurality of radial window flanges opposite each connection, the cross section of which is in the form of an isosceles trapezoid with rounded corners and a wide base on the side of the nuts, one of the disks being fixed to the turbine rotor shaft by a splined connection.

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