RU2211337C1 - Rotor of gas turbine engine multistage turbine - Google Patents

Abstract

FIELD: power and transport engineering. SUBSTANCE: invention can be used in aircraft and ground gas turbine plants. Invention is aimed at increasing reliability of operation by excluding inflow gas into rotor in case of breakage of outer labyrinth and non-localized destruction of engine. The problem can be solved only in case when labyrinth seals are placed in rotor of multistage turbine of gas turbine engine in rim part between neighbor disks on upper flanges. According to invention, labyrinth seal is made in form of two ring beams-labyrinths interconnected by outer and inner shells by means of movable ring fit. Neighbor beams-labyrinths are installed on inner shells with end face contact, and on outer shells, with preset clearance. Plates of beams-labyrinths are rigidly connected with upper flanges of neighbor disks in radial and axial directions. Diaphragms can be installed between lower flanges of neighbor disks. Said diaphragms provide direction of movement of cooling air flow inside rotor in process of operation of turbine excluding overheating of rotor. EFFECT: improved reliability in operation. 2 cl, 3 dwg

Description

 The invention relates to the field of energy and transport engineering and can be used in the construction of turbines for aircraft engines and gas turbine installations for ground use.

 A known design of a three-stage turbine of a gas turbine engine, in which labyrinth seals are placed between the rotor disks [1].

 A disadvantage of the known design is that the labyrinth seal between the disks is located at a small radius, the upper part of the disk web is washed with hot gases, therefore this design can be used only in low-temperature turbines. When using the design in high-temperature turbines, overheating and rupture of the rims along rim parts can occur.

 Closest to the claimed one is the rotor of a multi-stage turbine, in which the seals of the cavities between the stages of the turbine are made in the form of an annular labyrinth having a section of an I-beam. To ensure strength, the labyrinth is supported by a hub located at a smaller radius, in the zone of lower temperatures and voltages. The maze rim is connected to the hub by an annular web [2].

 However, this design has one significant drawback - in case of destruction of the outer rim of the labyrinth, hot gases can penetrate into the rotor. In this case, the canvas and the hub of the labyrinth itself, as well as the disks, and their destruction with non-localized consequences will be heated.

 The technical problem solved by the invention is to increase the reliability by eliminating gas leakage into the rotor during the destruction of the outer maze and non-localized destruction of the engine.

 This problem can be solved in the case when in the rotor of a multi-stage turbine of a gas turbine engine, in the rim of which between adjacent disks on the upper flanges there is a labyrinth seal, according to the invention, the labyrinth seal is made in the form of two annular labyrinth beams interconnected by external and inner shells using a movable annular landing, and on the inner shells adjacent maze beams are installed with an end contact, and on the outer shells - with a given gap While the web-maze beams rigidly fastened to the upper flanges of adjacent disks in the radial and axial directions.

 In addition, diaphragms can be installed between the lower flanges of adjacent discs.

 In this design, the labyrinth beams are interconnected along the outer and inner shells by means of a movable annular landing, and their canvases are rigidly fastened to the upper flanges of adjacent disks, thus forming an outer protective belt that prevents gas from entering the rotor to its power parts.

 Even in the case of destruction of the outer shell of the labyrinth beams when touching the combs of the labyrinths of the outer shell of the stator elements, rotor destruction does not occur, because adjacent labyrinth beams along the inner shells are installed with a movable annular landing and end contact, which prevents gas from flowing into the rotor.

 To ensure thermal expansion of the outer shells of the labyrinth beams in the axial direction, an axial clearance is provided, depending on the actual parameters, and based on structural considerations.

 In addition, the installation of elastic diaphragms between the lower flanges of adjacent disks is caused by the need to organize the direction of movement of cooling air inside the rotor.

 The invention is illustrated as follows.

 Figure 1 shows the rotor of a multi-stage turbine of a gas turbine engine of the claimed design. Figure 2 presents a view And figure 1. Figure 3 shows the hub part of the disks according to claim 2.

 The rotor consists of a shaft 1, a disk of the first stage 2 with working blades 3, a disk of the second stage 4 with working blades 5, a disk of the third stage 6 with working blades 7.

 Between the disks 2, 4 and 6 on the upper flanges 8 are labyrinth seals, which are made in the form of two annular beams-labyrinths 9, 10 and 11, 12.

 The labyrinth beams 9, 10, 11, 12 are interconnected along the outer 13 and inner 14 shells using a movable annular landing, forming an outer protective belt. On the outer shells 13 adjacent beams-labyrinths are installed with a given gap 15, and on the inner shells 14 - with the end contact.

 The disks 2, 4, 6 are in contact with each other by the lower flanges 16, 17 and 18, 19, and in the circumferential direction are fixed with pins 20, forming an internal power belt.

 The disk 6 using a remote flange 21 and a bolt 22 is attached to the shaft 1.

 The webs of the labyrinth beams 9, 10 and 11, 12 are rigidly fastened to the upper flanges 8 of the disks 2, 4, 6 with bolts 23.

 In the axial direction, the disks 2, 4 are pressed against the disk 6 by the coupling bolt 24.

 Additionally, between the lower flanges 16, 17 and 18, 19 can be installed diaphragm 25.

 The operation of the rotor is as follows.

 During the operation of the turbine, torque is supplied to the rotor shaft 1 from the working blades of the first stage 3, second stage 5 and third stage 7 through the corresponding disks 2, 4, 6, pins 20 and bolts 22. The outer protective belt, consisting of labyrinth beams 9 , 10 and 11, 12, prevents the ingress of hot gases inside the rotor.

 In the case of destruction of the outer shells 13 for any reason (for example, due to the destruction of the ridges of the labyrinths when they touch the stator elements), hot gases can enter the cavity between the webs of the labyrinth beams 9, 10 and 11, 12, but do not penetrate into the rotor to its power units, which eliminates the non-localized destruction of the engine. The elastic diaphragm 25 during the operation of the turbine allows you to organize the direction of movement of the cooling air flow inside the rotor and to prevent its overheating.

Sources of information
1. G.S. Skubachevsky. Aircraft gas turbine engines. Design and calculation of parts. M.: Mechanical Engineering, 1974, p. 113, Fig. 5.02.

 2. US patent 4645424, F 01 D 5/06, 11/02, 1987.

Claims (2)

 1. The rotor of a multi-stage turbine of a gas turbine engine, in the rim of which between adjacent disks on the upper flanges there is a labyrinth seal, characterized in that the labyrinth seal is made in the form of two annular labyrinth beams connected to each other along the outer and inner shells by means of a movable ring landing moreover, the adjacent labyrinth beams are installed with an end contact along the inner shells, and the clearance is set along the outer shells, while the canvases of the labyrinth beams are rigidly fastened s with the upper flanges of adjacent disks in the radial and axial directions.  2. The rotor of a multi-stage turbine of a gas turbine engine according to claim 1, characterized in that a diaphragm is installed between the lower flanges of adjacent disks.

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