RU2003821C1 - Inter-shaft bearing unit of turbomachine - Google Patents

Abstract

Usage: in aircraft gas turbine engine designs. SUMMARY OF THE INVENTION: An intermediate element is installed between the inner and outer shafts, made in the form of two concentric hollow cylinders interconnected by a radial wall. A cylinder of a smaller diameter is mounted on the inner shaft, an outer ring of the bearing is mounted on the inner surface of a larger diameter cylinder, and the inner ring is on the outer surface of the outer shaft 1 id

Description

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The invention relates to power and transport engineering and can be used in the construction of aircraft gas turbine engines.

A knot for connecting shafts of a twin-shaft gas turbine engine with an intermediate shaft is known, where an inter-shaft bearing 1 is used to limit the deflection of the inner shaft in the middle part between the bearings at the ends of the shaft.

However, this design does not ensure the stability of the radial play in the shaft bearing during engine operation, which can lead to slipping and wear of the bearing parts and to a decrease in the reliability of the assembly.

There is also known the design of an assembly of the intermounter support of the turbomachine, having a roller bearing, the outer ring of which is mounted on the drive shaft of the high pressure compressor (HPC), and the inner ring on the shaft of the rotor of the low pressure turbine (HPH) 2.

However, the rotational speed of the HPC rotor is significantly higher than the rotational speed of the low-pressure rotor; therefore, the outer ring of the shaft bearing has rotations higher than the inner. Under the action of centrifugal forces, the extraction of the outer ring significantly exceeds the extraction of the inner ring and the increase in the radial play in the bearing in operation is commensurate with the size of the mounting radial play of the inoperative engine. Thus, a drawback of the known design of the inter-shaft support assembly is that it cannot provide the optimal value of the radial backlash on a running engine, which causes the bearing to slip and wear. In order to eliminate slippage in this design, one can follow the path of reducing the number of rollers in a set (increasing the load on one roller). However, under certain conditions, this can lead to a significant increase in contact loads on bearing parts, their spalling and destruction.

The aim of the invention is to increase the reliability of the site of the inter-shaft support of the turbomachine

The goal is achieved in that the node of the inter-shaft support of the turbomachine, located between the bearings at the ends of the inner shaft, containing a roller bearing, according to the invention is equipped with an intermediate element made in the form of two concentric hollow cylinders interconnected by a radial wall, and a cylinder of a smaller diameter mounted on the inner the shaft, the outer ring of the bearing is mounted on the inner surface of the cylinder with a larger diameter, and the inner ring

bearing - on the outer surface of the outer shaft.

The drawing shows a diagram of the installation of the rotor of a turbine engine of a twin-gas turbine engine with an inter-shaft support assembly.

0 The HPC shaft 1 and the HPH shaft 2 are connected to each other by the HPC drive shaft 3, which is fastened with a nut 4. The inner ring 5 of the bearing 6 is located on the HPC shaft 1 and tightened by a nut 7, which is locked by a cup lock 8. The outer ring 9 of the bearing 6 by means of an intermediate element 10, it is connected to the HPH shaft 11. Lubrication and cooling of the bearing 6 are carried out through channels 12. Reset waste

0 of the oil is carried out through the holes 13 and 14. The bearing b is made with collars 15 on the inner ring 5.

The assembly of the turbomachine support shaft assembly is carried out in the following sequence. The shaft 3 of the HPC drive is installed on the shaft 1 of the HPC and tightened with a nut 4. The inner ring 5 of the bearing 6 with a set of rollers and a senator (not marked) are installed on the shaft 1 of the HPC,

0 then put the cup lock 8 and tighten with a nut 7, which is counter pressed by the cup lock 8. Then assemble the assembly consisting of an intermediate element 10, the outer ring 9 of the bearing 6, which

5 are fastened with a nut (not marked}. The assembled assembly is installed in the assembly of the spacer support with the outer ring 9 of the bearing on the rollers. The package of parts 16 is installed in the shaft 3 of the HPC drive and tightened with nut 17. After that, the theater rotor is inserted, then - TND with landing on the intermediate element 10.

The node operates as follows. On running engine inner ring 5

5 of the bearing 6 rests on the HPC shaft 1. The outer ring 9 of the bearing 6, through the intermediate element 10, is supported on the high pressure pump shaft 11, i.e. between the shaft 1 of the HPC and the shaft 11 of the high pressure pump through the bearing b and the intermediate element 10, a rigid connection is made, acting as an intermediate support between the two rotors.

The rotations of the outer ring 9 of the bearing 6 are lower than the rotations of the inner ring 5

5 bearings b. This leads to the fact that the stretch of the inner ring 5, rotating at high revolutions, is compensated by the stretch of the outer ring 9, which has lower revolutions but a larger mass. A set of rollers presses on the outer ring 9

and a separator. Thus, the radial play in the bearing 6 during operation is practically constant and equal to the mounting one.

Bearing lubrication is carried out as follows. Oil is supplied through channels 12 under the wings of the bearing cage 6, lubricating it. Oil is drained through the holes 13 and 14. The collars 15 of the bearing 6 do not prevent the discharge of oil, dirt and products from the nose, as located on the inner ring 5 of the bearing 6.

Thus, in comparison with the known design of the inter-shaft assembly

Claims (1)

The claims INTERMEDIATE SUPPORT ASSEMBLY OF A TURBO MACHINE, comprising a roller bearing located between the supports located at the ends of the internal shaft, one of the rings of which is located on the external shaft, characterized in that the assembly is provided with an intermediate element turbomachine bearings are more reliable by achieving stability of radial play in the bearing, avoiding contact of the bearing with parts during assembly, and also improving oil drainage conditions, removing dirt and wear products. (56) 1. USSR Copyright Certificate No. 1563302, cl. F 02 C 7/00, published. 1968. 2, Aircraft dual-circuit turbojet engine D-ZOKU. Technical description. M.: Mechanical Engineering, 1975, p.24, 165. fifteen filled in the form of two concentric hollow cylinders interconnected by a radial wall, the cylinder of a smaller diameter mounted on the inner shaft, the outer ring of the bearing mounted on the inner surface of the cylinder of larger diameter, and the inner ring of the bearing on the outer surface of the outer shaft. # S U1315 8 7 I eleven