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ADDITIVELY-MANUFACTURED ENGINE STRUCTURAL COMPONENT WITH INTEGRAL GRID

IP.com Disclosure Number: IPCOM000249758D
Publication Date: 2017-Mar-31

Publishing Venue

The IP.com Prior Art Database

Abstract

An engine component such as a casing incorporates an integral stiffening grid and is produced by an additive manufacturing process.

This text was extracted from a PDF file.
This is the abbreviated version, containing approximately 23% of the total text.

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ADDITIVELY-MANUFACTURED ENGINE STRUCTURAL COMPONENT WITH

INTEGRAL GRID

ABSTRACT

[0001] An engine component such as a casing incorporates an integral stiffening grid and

is produced by an additive manufacturing process.

BACKGROUND

[0002] This disclosure relates generally to gas turbine engines such as turbojet, turbofan,

and turboprop/turboshaft engines, as well as derivative marine and industrial power

plants.

[0003] A typical gas turbine engine includes one or more rotating shafts which carry

turbomachinery blading which is in turn enclosed by one or more stationary casings of

the engine.

[0004] These casings carry large structural loads and pressure loads, and surround and

locate components which must be contained at all times. For example in the case of a

failure of rotating turbomachinery, if the broken parts exit the casing it may damage an

airframe or cause injury. Such structures could be described as critical major static

structures.

[0005] It is known that engine components, including static casings, can be designed to

have a high strength and stiffness at a light weight by using relatively thin materials

provided with an integral grid of stiffening ribs. One known example of such a structure

has the stiffening ribs arranged in an array of equilateral triangles and is referred to as an

"isogrid" pattern.

[0006] One problem with integral stiffening ribs is that they are difficult and expensive to

manufacture using conventional methods in which material is removed from a billet or

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from a cast or forged rough workpiece.

[0007] Described herein is a component with an integral grid of reinforcing ribs,

produced by an additive manufacturing process.

BRIEF DESCRIPTION OF THE DRAWINGS

[0008] The concept may be best understood by reference to the following description

taken in conjunction with the accompanying drawing figures, in which:

[0009] FIG. 1 is a schematic cross-sectional view of a representative aircraft gas turbine

engine;

[0010] FIG. 2 is a side view of an exemplary exhaust casing manufactured according to

the principles described herein and suitable for incorporation into the engine of FIG. 1;

[0011] FIG. 3 is an end view of the exhaust casing of FIG. 2;

[0012] FIG. 4 is a cross-sectional view taken along lines 4-4 of FIG. 3; and

[0013] FIG. 5 is a schematic view of an additive manufacturing apparatus.

DETAILED DESCRIPTION OF THE CONCEPT

[0014] Illustrated in FIG. 1 is an exemplary turbofan gas turbine engine 10 for powering

an aircraft (not shown) in flight. The engine 10 is intended to be a representative example

of one type of engine that can incorporate static components as described herein.

[0015] The engine 10 is axisymmetrical about a longitudinal or axial centerline axis 12

and has a fan section 14 upstream of a core engine 13. The core engine 13 includes, in

serial flow communication, a multistage axial high pressure compressor 16, an annular

combustor 18, and a high pressure turbine 20 suitably joined to the...