RU2575257C1 - Turbine machine rotor made out of dissimilar materials - Google Patents

Abstract

FIELD: machine building.

SUBSTANCE: turbine machine rotor contains the first and second sections of impellers, made out of unweldable with each other materials, creating a non-detachable connection via an intermediate element. The intermediate element has areas with the weldability corresponding to the first and second impellers, and is welded by one end to the first impeller, and by another end to the second impeller. The intermediate element is made out of two flanges, each of them is made out of the material having weldability with the material of the adjacent first or second impellers. The flanges of the intermediate element are connected by a permanent connection.

EFFECT: invention ensures the permanent connection of the rotor elements made out of dissimilar unweldable materials, without reducing the strength of the connection relatively to the strength of the materials used in the rotor sections.

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Description

The invention relates to the field of turbo-mechanical engineering and, in particular, can be implemented in the design of rotors of multi-stage compressors and turbines.

The closest analogue of the invention is the known turbomachine rotor containing the first and second sections of the impellers made of non-weldable materials, forming an integral connection through an intermediate element. An intermediate element including weldable portions corresponding to the first and second impellers is welded at one end to the first impeller and at the other end to the second impeller. The intermediate element is a single two-alloy and has a first region containing a material that is uniform with the first material, and a second region containing a material that is uniform with the second material, different from the material of the first region. The intermediate element also has a molded transition region between the first and second region, and at least a portion of the said region includes a combination of the first and second material / RU 2480316 C2, B23K 31/02, 04/27/2013, prototype /.

The disadvantage of the prototype is the low strength of the welded joint due to various physico-chemical properties of the materials being joined.

The objective of the invention is to reduce the mass of the compressor or turbine, increasing the reliability of the site.

EFFECT: obtaining an integral connection of rotor elements made of dissimilar non-weldable materials without reducing the connection strength relative to the strength of materials used in the rotor sections, as well as simplifying the manufacture of an intermediate element.

The expected technical result is achieved in that in the rotor of the turbomachine containing the first and second impellers made of non-weldable materials, forming a permanent connection through an intermediate element, including sections with weldability, corresponding to the first and second impellers, welded at one end to the first working wheel, and the other end to the second impeller, according to the proposal, the intermediate element is made of two flanges, each of which is made of a material having weldability with the material of the adjacent first or second impellers, while the flanges of the intermediate element are connected by an integral connection.

The present invention can be implemented for connecting impellers, disks, sections, consisting of several disks, in any known design schemes of turbomachine rotors.

Since different parts of the rotor are exposed to different temperatures during operation of the turbomachine, the implementation of structural elements from various materials allows to obtain the highest specific characteristics of the node. The physicochemical properties of most dissimilar materials do not allow to obtain a high-quality one-piece non-mechanical (welded, soldered, glue) joint, which is the optimal type of connection of rotor sections in terms of reliability and weight. The term "dissimilar materials" refers to alloys with different chemical composition. The use of a detachable mechanical connection is associated with a decrease in reliability, manufacturability of the assembly and an increase in the mass of the assembly.

The proposed design of the intermediate element allows you to make high-quality one-piece non-mechanical connection of the rotor elements with the intermediate element. In turn, the parts of the intermediate element are connected by an integral mechanical connection that provides the required strength characteristics in combination with the minimum weight, dimensions, ease of manufacture and maximum reliability.

The connected rotor elements can be made of the following combinations of the first and second materials: titanium-aluminum; titanium steel; heat-resistant titanium alloys on various bases; metal-various composites. The choice of materials of the parts of the intermediate element should ensure the implementation of high-quality welded joints with the corresponding elements of the rotor. To connect the rotor elements with the parts of the intermediate element, any known type of welding of the rotors is possible, providing a connection of the required quality, such as diffusion, beam, friction welding. The permanent mechanical connection of the parts of the intermediate element can be a rivet connection, a pin, welded connecting elements, soldering, etc.

The design of the intermediate element should provide a minimum weight and dimensions, high manufacturability, the required strength characteristics, as well as maintaining the strength characteristics at the required level throughout the life of the product. The optimal design of the intermediate element is presented in the form of two annular flanges with surfaces for welding with rotor elements. The number of integral mechanical joints on the flange of the intermediate element must be at least two, maximum based on the required strength conditions.

The invention is illustrated by figures 1-3.

FIG. 1 - general view of the rotor;

FIG. 2 is a general view of an intermediate connecting element;

FIG. 3 is an embodiment of an intermediate connecting element.

1 - turbomachine rotor;

2, 3 - the first and second elements of the rotor;

4 - an intermediate element;

5, 6 - flanges;

7 - welds;

8 - rivet;

9 - sleeve;

10 - annular landing belt;

11 - grooves at the ends of the flanges;

12 - hole in the flanges;

13 - end thrust surface of the sleeve;

14 - washer.

The rotor 1 of the turbomachine consists of the first and second elements 2, 3, which are impellers or sections consisting of several impellers made of dissimilar materials, such as titanium and nickel alloys. Impellers 2, 3 are connected by an intermediate element 4, consisting of two flanges 5, 6. Flange 5 is welded to the first element (impeller) 2, flange 6 is welded to the second element (impeller) 3, forming welds 7. Flanges 5, 6 are made of materials providing the possibility of obtaining a welded joint with the corresponding impellers 2, 3 of the rotor 1, for example, titanium and nickel alloys, respectively. Flanges 5, 6 are interconnected by one-piece mechanical connection, for example, power rivets 8 or bushings 9.

The assembly of the elements of the rotor 1 in accordance with the invention is carried out as follows in three stages.

At the first stage, an intermediate connecting element 4 is assembled, made in the form of two flanges 5, 6, connected by an integral mechanical connection in two ways.

According to the first embodiment, the flanges 5, 6, consisting of dissimilar materials that are not welded together, for example, from a titanium alloy and a heat-resistant alloy based on nickel, are centered on the annular landing belt 10 and crimped. To create the necessary mounting interference on the end surfaces of the flanges 5, 6, grooves can be made 11. Holes 12 are jointly made in the flanges 5, 6. Power rivets 8, pre-heated to the state of superplasticity, are installed in the holes 12, which are installed in the conductor, allowing you to install all the rivets 8 simultaneously along all holes 12 of the flanges 5, 6. Then, the end surfaces of the rivets 8 are deformed, thereby achieving an integral connection of the elements of the rotor 2, 3.

According to the second variant, sleeves 9 with end stop surfaces 13 on one side are installed in holes 12 of flanges 5, 6 instead of rivets 8. On the other hand, washers 14 are mounted on the cylindrical parts of the bushings 9 with an emphasis on the counter surface of the flange 6. The washers 14 are welded around the perimeter of the joints with the bushings 9 and an integral connection of the rotor elements 2, 3 is obtained.

At the second stage, the assembled intermediate element 4 is successively connected by welding with adjacent elements of the rotor 2, 3.

In the third stage, the assembled rotor 1 is installed in a turbomachine with the required adjustments.

The application of the invention allows to reduce the cost of the product life cycle by increasing the level of its specific parameters and reliability due to improvement of the design.

Claims (1)

A turbomachine rotor containing the first and second sections of the impellers made of non-weldable materials, forming an integral connection through an intermediate element having weldable sections corresponding to the first and second impellers, welded at one end to the first impeller and the other end to the second impeller, characterized in that the intermediate element is made of two flanges, each of which is made of a material having weldability with the material adjacent first and second impellers, the flanges of the intermediate element are connected integrally compound.

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