DE102010032984A1 - Method for replacing frictionally added attachment e.g. suspension socket of multipart airplane thruster, involves fixing to-be-attached portion onto hole that is formed in multipart airplane thruster - Google Patents

Abstract

The method involves removing the frictionally added attachment from the multipart airplane thruster (1) by operation of a mobile lathe (2). To-be-attached portion is fixed onto the hole (1.1) that is formed in the multipart airplane thruster. The mobile lathe is fixed in a predetermined position of the multipart airplane thruster. The mobile lathe is actuated and is fixed permanent or electromagnetic at the surface of multipart airplane thruster. Independent claims are included for the following: (1) usage of mobile lathe; and (2) method for teaching fixation of mobile lathe in predetermined position on multipart airplane thruster.

Description

The invention relates to a method for replacing a frictional-fitted attachment, in particular a suspension bushing, a multi-part aircraft engine, as well as a teaching and the use of a mobile lathe for carrying out a method according to the invention.

Aircraft engines, such as those in the US 7,100,358 B2 described include a plurality of interconnected parts, including, for example, a turbine exhaust case (TEC), which is releasably secured by means of TEC bolt on the engine body, which in turn is releasably secured by means guided in suspension bushing engine bolts on the aircraft.

For example, if these suspension bushings are damaged, worn or loose, they must be replaced. For this purpose, so far the engine is suspended by loosening the engine bolts and, among other things, by loosening the TEC bolts, the flange in which the engine bolts receiving holes are formed, removed from the disassembled engine to better edit it as a single item can. For example, proposes the EP 0 868 372 B1 a corresponding transport device before.

Disadvantageously, this dismantling of the engine into individual parts after assembly, in particular the attachment of the TEC, requires a complex test run of the reassembled multipart aircraft engine.

The invention has for its object to improve the replacement of a frictionally joined attachment of a multi-part aircraft engine, in particular nozzle or gas turbine engine.

This object is achieved by a method having the features of claim 1. Advantageous developments are the subject of the dependent claims.

The present invention is based on the idea of replacing the frictionally attached attachment, in particular a suspension bushing, no longer on the item of the disassembled engine, but in situ on the multi-part, preferably suspended, engine.

For this purpose, according to the invention a mobile lathe, in particular a drill, releasably fixed to the multi-part aircraft engine. This is done according to a preferred embodiment in at least one predetermined position on the multi-part aircraft engine, which is given according to the location of the built-in attachment. For this purpose, the mobile lathe can advantageously be fixed by means of a gauge on the aircraft engine, which positions the mobile lathe in the predetermined position. In order to be able to use the same lathe for different attachments and / or aircraft engines or different lathe, for example for drilling and rubbing, for the same attachment, according to a preferred embodiment several different gauges are provided, which in particular can define different positions of the mobile lathe, and depending on the work step, to be replaced attachments or engines selected a suitable one of these.

By means of the lathe fixed to the engine, a first attachment to be removed and, preferably, sequentially or in parallel, one or more additional attachments to be removed can be removed, in particular drilled or turned off.

Likewise, by means of the lathe fixed in the same or another position on the engine, a first receptacle of a first attachment to be inserted, and preferably one or more further receptacles of additional attachments to be inserted, can be processed, preferably machined, and in particular rubbed sequentially or in parallel. A receptacle may in particular have a bore and / or a projection, with which an outer or inner surface of the attachment is frictionally engaged, in particular by a press fit, preferably by a shrink fit, is added.

Additionally or alternatively, by means of the fixed in the same or another position on the engine lathe a first replaced attachment and preferably sequentially or in parallel one or more other replaced attachments edited, preferably machined, in particular rubbed.

The mobile lathe can be fixed positively and / or non-positively, in particular by means of one or more permanent and / or electromagnets, directly or via a gauge on the multi-part aircraft engine, which in turn also preferably positive and / or non-positive, in particular permanent and / or electromagnetically fixed to the multi-part aircraft engine. Advantageously, an engine-friendly and nevertheless precise fixation is ensured.

A parallel or sequential replacement of several, in particular aligned attachments not only reduces advantageous processing time and - effort, but can advantageously additionally lead a shaft or a tool of the lathe and thus increase the machining accuracy. For this purpose, additionally or alternatively, a gauge by means of which the lathe is fastened to the engine can have a corresponding guide for a shaft of the lathe.

To form a shrink fit, an attachment to be joined, in particular by means of liquid nitrogen, is preferably cooled prior to insertion. Additionally or alternatively, a receptacle in the form of a bore or a part of the multi-part engine having this, preferably only slightly and / or partially heated. Conversely, before being inserted, an attachment to be joined can be heated and / or a receptacle in the form of a projection can be cooled.

According to a preferred embodiment, after the removal of an attachment to be removed, the editing of a recording of an attachment to be joined and / or the joining of an attachment to be joined, the receptacle or the replaced attachment respectively locally to damage, especially cracks, tested to early and to detect damage in a readily accessible manner.

Further features and advantages emerge from the subclaims and the exemplary embodiment. This shows, partially schematized, the only:

1 the replacement of two suspension bushes according to an embodiment of the present invention.

1 shows a detail in a partial section of a multi-part aircraft engine 1 with two ring-shaped mounting flanges 1.10 . 1.20 , in which spaced axially aligned bores 1.1 respectively. 1.2 are designed for receiving suspension bushes.

To such suspension bushes, of which in 1 a non-existing in the illustrated method step suspension bushing 4 for clarity in the installed position indicated by dashed lines, replace, one to the respective engine or one of several over the circumference of the flanges 1.10 . 1.20 Distributed suspension bushing adapted gauge 3 by means of in 1 dashed lines indicated, in holes in the engine 1 positive engaging projections 3.1 Positioned in a predetermined position and fixed by means of permanent or electromagnet (not shown) on the engine.

At the lesson 3 becomes a mobile drill 2 fixed, in turn, projections 2.2 in drilling in teaching 3 interlock positively and the drill 2 by means of permanent magnet or electromagnet (not shown) on the gauge 3 is releasably secured. Of course, here are other fasteners, such as a screwing the drill 2 with the teaching 3 , possible. It can be seen that by using another teaching with differently shaped projections or holes, the drill 2 also at other positions of the engine 1 or on other types of engines in predetermined positions can be fixed.

With the drill, its shaft in addition to increasing the accuracy through the gauge 3 can be performed (not shown), are first successively or partially simultaneously drilled out the old suspension bushings to be replaced.

Then, for example, by means of a subsequent reamer or after a tool change, the holes freed from the old bushings 1.1 . 1.2 with the (in the embodiment against the drill replaced) reamer 2.1 reworked as in 1 is shown. It can be seen that both holes 1.1 . 1.2 partially successively and partially processed simultaneously, so that an additional guidance of the drill tool 2.1 is reached.

After the quality of the reworked hole has been determined by a local crack test, the new suspension bushes to be inserted are cooled by liquid nitrogen, the flange areas which are the holes 1.1 . 1.2 have, slightly heated, and the new suspension bushings joined into the holes, where they are frictionally joined after temperature compensation and appropriate partial thermal deformation with appropriate tension through the shrink fit.

Subsequently, the inner diameter of the new suspension bushes by a correspondingly smaller reamer by means of the drill 2 rubbed to the desired final size and then locally crack tested (not shown).

Because the replacement by means of the mobile drill 2 in situ on the suspended, but not further disassembled engine 1 no test run is required, as has been the case so far, especially after a reduction of the TEC.

LIST OF REFERENCE NUMBERS

1

Jet Engine

1.1, 1.2

Bore (intake)

1.10, 1.20

flanges

2

Drilling machine (lathe)

2.1

reamer

2.2

head Start

3

Base plate (gauge)

3.1

head Start

4

Suspension bush in installation position

QUOTES INCLUDE IN THE DESCRIPTION

This list of the documents listed by the applicant has been generated automatically and is included solely for the better information of the reader. The list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions.

Cited patent literature

• US 7100358 B2 [0002]
• EP 0868372 B1 [0003]

Claims (10)

Method for exchanging a frictionally fitted attachment, in particular a suspension bushing ( 4 ), a multi-part aircraft engine ( 1 ), characterized in that a mobile lathe ( 2 ) releasably fixed to the multi-part aircraft engine and removed by means of the mobile lathe a first to be removed attachment, in particular drilled, a first receptacle of a first attachment to be joined, in particular a bore ( 1.1 ), and / or an exchanged attachment worked, in particular rubbed. A method according to claim 1, characterized in that the mobile lathe is fixed in a predetermined position on the multi-part aircraft engine. Method according to claim 2, characterized in that one of several teachings ( 3 ) is selected and the mobile lathe is fixed by means of this teaching in a predetermined position on the multi-part aircraft engine. Method according to one of the preceding claims, characterized in that the mobile lathe is positively and / or non-positively, in particular permanently and / or electromagnetically fixed to the multi-part aircraft engine. Method according to one of the preceding claims, characterized in that by means of fixed in the same position mobile lathe parallel to or sequentially after removal of the first part to be removed and / or machining the first receptacle ( 1.1 ) and / or the first replaced attachment removed a second to be removed attachment and / or a second receptacle ( 1.2 ) of a second attachment to be joined and / or a second replaced attachment ( 4 ) is processed. Method according to one of the preceding claims, characterized in that prior to insertion of an attachment to be joined by a ( 4 ) and a receptacle of the attachment to be joined, in particular by means of liquid nitrogen, cooled and / or another of the attachment to be joined and the receptacle ( 1.1 . 1.2 ) is heated. Method according to one of the preceding claims, characterized in that after removal of an attachment to be removed, editing a recording of a fixture to be joined and / or joining a fixture to be joined, the receptacle or the replaced attachment locally to damage, especially cracks, is checked , Method according to one of the preceding claims, characterized in that an attachment to be removed is removed, a receptacle of an attachment to be joined and / or a replaceable attachment is processed without separating a receptacle having part of the multi-part aircraft engine from the rest of the aircraft engine. Use of a mobile lathe ( 2 ) in a method according to any one of the preceding claims. Teaching ( 3 ) for fixing a mobile lathe ( 2 ) in a predetermined position on a multi-part aircraft engine according to claim 3.

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