DE102012204777B4 - Method for producing a cladding element and cladding element - Google Patents

Abstract

A method for producing a cladding element (1) for a combustion chamber of a turbo-engine, which has a base body (2) and several integral fastening means (10) for fastening to a support element, with the steps: - Separating at least one old fastening means (10) from an old one Cladding element (16), - producing the base body (2), at least one connection area (24) being provided on the base body (2) for connecting the old fastening means (10), and - connecting the at least one old fastening means (10) to the Base body (2) in the connection area (24) by means of rotary friction welding.

Description

The invention relates to a method for producing a cladding element for a combustion chamber of a turbomachine and such a cladding element.

Combustion chambers in turbomachines such as aircraft engines are intended to enable stable combustion with optimum fuel utilization in the smallest space and for a wide range of fuel / air ratio. Depending on the application and requirement, there are different types of combustion chamber.

An annular combustion chamber is often used in engines with axial compressor. It has an annular flame tube and, for example, two annular secondary air channels for cooling. Tube combustion chambers, however, are often used in engines with centrifugal compressors, since the air flow is already divided by outlet diffusers of the centrifugal compressor. An entire engine combustion chamber has, for example, eight to twelve concentrically arranged around the engine tube combustion chambers, each associated with its own secondary air duct. A ring tube combustion chamber is a combination of tube and ring combustion chamber. All flame tubes of the annular tube combustion chambers are assigned a common secondary air channel.

The flame tube or the flame tubes of the combustion chambers is / are lined because of the high temperature with shingles made of heat-resistant material. The shingles or cladding elements have a plate-shaped base body, which is releasably fastened by means of rear fastening means to a support element. Due to the high thermal stress, however, the cladding elements are exposed to high wear. This manifests itself, for example, in spent areas of the body, which regularly requires an exchange of the respective damaged cladding element. Due to the heat-resistant base material, however, the cladding elements are very expensive.

From the publication US 2005/0 028 527 A1 For example, a method for repairing an air-cooled lining element for a combustion chamber of a turbomachine is known. The cladding element has a plurality of integral, mutually spaced, radially outwardly projecting protrusions or pins which are circulated during operation of cooling air. Often, such cladding elements z. B. damaged by burning in the edge area. In the proposed solution, a damaged edge area is separated and replaced by a corresponding repair element. When attaching the repair element, make sure that the flow paths between the pins are not disturbed or interrupted in the joint area. In other words, the pin pattern should remain as unchanged as possible in the joint area.

The publication DE 199 59 292 A1 relates to a method of manufacturing a gas turbine combustor. The cladding elements are integrally connected to each other by laser welding. Such a design makes later required repairs.

The object of the invention is to provide a method for producing a cladding element for a combustion chamber of a turbomachine with a reduced amount of virgin material and such a cladding element.

This object is achieved by a method having the features of patent claim 1 and by a lining element having the features of patent claim 6.

In a method according to the invention for producing a cladding element for a combustion chamber of a turbomachine, which has a main body and a plurality of integral fastening means for attachment to a support element, at least one old attachment means is separated from an old cladding element. In addition, a base body is produced, to which at least one connection area for connecting the old fastening means is provided. Subsequently, the at least one old fastening means is connected to the base body in the connection region by means of rotary friction welding.

The solution according to the invention is based on the principle of reuse. For this intact parts of an old cladding element are integrated into a new cladding element, whereby new material is reduced to the construction of the cladding element. In this case, the fastening means are particularly suitable, since they were arranged outside a hot gas path and thus were not thermally highly loaded or are. A material fatigue of the fasteners is thus not to be feared or almost impossible. In addition, the fasteners are intensively cooled by a secondary air flow. Rotational friction welding makes it possible to use the solution according to the invention for materials which are not suitable for fusion welding, since the melting point is not exceeded in rotary friction welding and typical faulty images of fusion-welded joints can thus not arise. Exemplary materials are nickel alloys such as the high-alloyed nickel alloy B1900 + HF.

In one embodiment, new fasteners are integrally formed in the manufacture of the body, which are reduced by the number of attachment areas. As a result, only as many Rotationsreibschweißvorgänge necessary as old fasteners are reused.

In an alternative embodiment, after the manufacture of the body new fasteners are connected by means of rotary friction welding, which are reduced by the number of old fasteners. This embodiment allows a separate from the body and thus parallel production of the fastening means, whereby the production of the cladding element is shortened in time.

Preferably, the base body is poured. In particular, casting allows for repeatable high dimensional accuracy and complete or nearly complete omission of mechanical post-processing allowances.

In all embodiments, it is preferred if a thermal protection layer and / or an adhesive layer is / are applied to the flame side. Preferably, the at least one weld is reworked for this purpose, for example, smoothed and / or cleaned. By the subsequent application of the at least one layer of the base body for rotational friction welding can be easily clamped because no consideration must be taken to any damage to be protected layers.

A preferred trim element for a combustion chamber of a turbomachine has a main body and a plurality of integral fasteners, wherein at least one fastener is a reusable old fastener. Such a cladding element is characterized by a reduced use of virgin material.

Other advantageous embodiments of the invention are the subject of further subclaims.

In the following preferred embodiments of the invention will be explained in more detail with reference to schematic representations. Show it:

1 a front view of a cladding element according to the invention,

2 a rear view of the cladding element according to the invention,

3 a front view of an old paneling element,

4 a rear view of the old paneling element,

5 Fastener and body of the old cladding element in a separate state,

6 a main body of the new cladding element,

7 an integration of the old fasteners in the body, and

8th a front view of the cladding element according to the invention.

In the figures, the same structural elements have the same reference numerals, wherein in several identical structural elements in a figure, only one element is provided with a reference numeral.

In the 1 and 2 is an inventive cladding element 1 for lining a flame tube of a turbomachine such as an aircraft engine or a stationary gas turbine. The flame tube, for example, forms part of an annular combustion chamber. The cladding element 1 or the shingle has a plate-shaped, slightly curved body 2 with a concave front or flame side 4 and a convex rear side arranged opposite thereto 6 , In the circumferential direction of the combustion chamber and thus in the longitudinal direction of the cladding element 1 are in the body 2 a multitude of adjacent passages 8th formed, extending from the back 6 through the main body 2 to the flame side 4 extend. In particular, the passages serve 8th for supplying mixed and / or cooling air into the flame tube. At the back 6 and thus the back of the body 2 are a variety of pen-like fasteners 10 arranged. The embodiment shown has four passages 8th and five fasteners 10 on.

The main body 2 is a casting and consists of a heat-resistant base material such as a high-alloy nickel alloy, in particular B1900 + HF. In the assembled state are a variety of the cladding elements 1 arranged side by side, one behind the other and nested that a lined flame tube is formed with a closed or gap-free and continuous inner peripheral surface.

To protect the body 2 high temperatures is the flame side 4 entire area with a heat protection layer 12 Mistake. In addition to an increase in the temperature resistance of the body 2 causes the heat protection layer 12 an improved oxidation resistance and erosion resistance and generally improved protection of the body 2 from foreign bodies. In addition, the heat protection layer protects 12 the main body 2 in particular, in front of a so-called calcium-magnesium-aluminum-silicate (CMAS) attack, which occurs, for example, when dirt that has accumulated on upstream blades of the turbomachine dissolves. To improve the properties of the thermal insulation layer 12 this is about an adhesive layer 14 on the flame side 4 applied. The adhesive layer 14 preferably consists of a MCrAlY material system. "M" stands for the metallic base material nickel or cobalt or for an alloy of these two base materials. Examples of MCrAlY material systems are NiCrAlY, CoCrAlY or CoNiCrAlY. The adhesive layer 14 However, it can also be used alone as a corrosion-resistant layer.

The fasteners 10 serve for fastening the cladding elements 1 on a support element, not shown. In the embodiment shown, the fastening means 10 Setscrews, the material fit with the body 2 are connected and thus formed integrally with this. They preferably consist of the same heat-resistant material as the main body 2 and thus made of a heat-resistant nickel-based alloy. The fasteners 10 are by means of rotary friction welding at the back 6 of the basic body 2 tethered. The rotary friction welding has the advantage that the melting point of the base material of the body 2 and the fastener 10 is not exceeded and therefore typical defects of fusion welds can not arise. In addition, the welded joint is insensitive to high temperatures occurring in the combustion chamber and no welding filler material is required.

In the 3 and 4 is an old paneling element that has been in operation 16 shown. This points to a longitudinal side of his main body 18 destroyed areas 20 on, which are burned due to the high thermal load within the flame tube. Back fastening means 10 but are undamaged.

The following is an inventive method for producing the cladding element 1 to replace the old paneling element 16 based on the 5 to 8th explained in more detail:
As in 5 is shown, an old and exchangeable cladding element 16 provided. The fasteners 10 of the old paneling element 16 are inspected for condition and in case of release for further use or reuse from the body 18 separated. In the embodiment shown, all five fasteners 10 suitable for reuse. To the axial length of the fasteners 10 They get at their foot sections 22 from the main body 18 separated or cut off. Should for the production of the new cladding element 1 not enough old fasteners 10 available, so can the missing fasteners of other old paneling elements 16 be removed or replace the missing fasteners with new fasteners.

In addition, as in 6 implied, a basic body 2 free from the fasteners 10 cast as a new part. The passages 8th Be right when casting the body 2 or subsequently introduced as holes in these. Further, as indicated by the small circles, a plurality of connection areas 24 for connecting the fastening means 10 of the old paneling element 16 provided on the back. The connection areas 24 can be used as simple, not particularly machined surface areas of the back 6 of the basic body 2 or, for example, with blunt to compensate for axial length losses of the fasteners 10 be educated. Since in the embodiment shown all five fasteners 10 are reusable, there are five connection areas 24 outlined.

After the production of the main body 2 be like in 7 shown the fasteners 10 in the connection areas 24 each by means of her foot section 22 tethered. The connection takes place by means of rotary friction welding, wherein the fastening means 10 each clamped in a corresponding receptacle and rotating about its longitudinal axis under axial pressurization against the main body 2 in the respective connection area 24 be pressed. The main body 2 is firmly clamped and is not moved during rotational friction welding. After the connection of the fasteners 10 to the body 2 their welding or connecting seams are reworked as needed, for example. Smoothed, cleaned and the like.

After reworking the welds, as in 8th shown the adhesive layer 14 and the heat-insulating layer 12 on the flame side 4 and thus applied on the front side. The cladding element 1 is now made and can be used as a replacement for the old cladding element 16 be mounted in the flame tube.

Disclosed are a method for producing a lining element for a combustion chamber of a turbomachine, to the base of a plurality of integral fasteners are attached, wherein at least some of the fasteners are reused used fasteners of exchangeable cladding elements, which are connected by means of rotary friction welding to the body, and such manufactured cladding element.

LIST OF REFERENCE NUMBERS

1

cladding element

2

body

4

Flash page

6

back

8th

passage

10

fastener

12

Thermal protection layer

14

adhesive layer

16

old paneling element

18

body

20

Area

22

foot section

24

connecting region

Claims (6)

Method for producing a cladding element ( 1 ) for a combustion chamber of a turbomachine, which has a base body ( 2 ) and a plurality of integral fasteners ( 10 ) for attachment to a support member, comprising the steps of: - separating at least one old fastener ( 10 ) of an old cladding element ( 16 ), - producing the main body ( 2 ), wherein on the base body ( 2 ) at least one connection area ( 24 ) for connecting the old fastening means ( 10 ), and - bonding the at least one old fastening means ( 10 ) on the base body ( 2 ) in the connection area ( 24 ) by means of rotary friction welding. Method according to claim 1, wherein in the production of the basic body ( 2 ) new fasteners are formed integrally by the number of attachment areas ( 24 ) are reduced. Method according to claim 1, wherein after the production of the basic body ( 2 ) new fasteners are attached by means of rotary friction welding which increases the number of old fasteners ( 10 ) are reduced. Method according to claim 1, 2 or 3, wherein the basic body ( 2 ) is poured. Method according to one of the preceding claims, wherein the cladding element ( 1 ) on the flame side with a heat protection layer ( 12 ) and / or an adhesive layer ( 14 ) is coated. Cladding element ( 1 ) for a combustion chamber of a turbomachine, produced according to one of the preceding claims.

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