Hollow fan blade with stir welded cover support

Patent metadata

Field	Value
Publication number	US-2016305443-A1
Application number	US-201415102155-A
Country	US
Kind code	A1
Filing date	Dec 16, 2014
Priority date	Dec 16, 2013
Publication date	Oct 20, 2016
Grant date	—

Abstract

An airfoil for a turbine engine includes an airfoil body with a cover mounting support, a first cover, and a second cover. The airfoil body includes a solid perimeter portion surrounding a recess formed into at least one of a suction side and a pressure side of the airfoil body, while the cover mounting support extends through the recess. The first cover can be engaged with a first edge of the recess and joined to a first portion of the cover mounting support by a first stir weld. The second cover can be engaged with a second edge of the recess, and joined to a second portion of the cover mounting support by a second stir weld.

First claim

1 . An airfoil comprising:
an airfoil body including a solid perimeter portion surrounding a recess formed into at least one of a suction side and a pressure side of the airfoil body; a cover mounting support extending through the recess; a first cover engaged with a first edge of the recess and joined to a first portion of the cover mounting support by a first stir weld; and a second cover engaged with a second edge of the recess, and joined to a second portion of the cover mounting support by a second stir weld.

2 . The airfoil of claim 1 , wherein the first cover and the second cover define a central portion of an airfoil sidewall surrounded by a perimeter portion of the airfoil body.

3 . The airfoil of claim 2 , wherein the airfoil sidewall is at least one of: a suction sidewall, and a pressure sidewall.

4 . The airfoil of claim 2 , further comprising:
a third cover portion disposed between the first and second cover portions.

5 . The airfoil of claim 4 , wherein the third cover portion bridges the first and second cover portions, and forms a third portion of the sidewall.

6 . The airfoil in claim 1 , wherein the airfoil body comprises titanium or an alloy thereof.

7 . The airfoil of claim 1 , wherein the cover mounting support comprises a first rib extending spanwise from a root side to a tip side of the recess.

8 . The airfoil of claim 7 , wherein the cover mounting support further comprises a second spanwise rib equally spaced from the first spanwise rib.

9 . The airfoil of claim 7 , wherein the cover mounting support separates the recess into a forward portion and an aft portion.

10 . The airfoil of claim 1 , further comprising:
a plurality of reinforcement ribs disposed in the recess.

11 . The airfoil of claim 10 , wherein at least one of the plurality of reinforcement ribs is curved between a leading edge of the airfoil and the cover mounting support.

12 . The airfoil of claim 10 , further comprising:
a porous material disposed between individual ones of the plurality of reinforcement ribs.

13 . A turbofan engine comprising:
a compressor section in flow series with an upstream core inlet; a combustor section adapted to combine fuel with compressed air received from the compressor which is combusted to form a working fluid; a turbine section adapted to convert energy of the working fluid into rotation of at least one shaft; and a fan section driven by rotation of the at least one shaft, the fan section including a plurality of airfoils connected to a fan hub, each of the plurality of airfoils comprising:
an airfoil body including a solid perimeter portion surrounding a recess formed into at least one of a suction side and a pressure side of the airfoil body;
a cover mounting support extending through the recess;
a first cover engaged with a first edge of the recess and joined to the cover mounting support by a first stir weld; and
a second cover engaged with a second edge of the recess, and joined to the cover mounting support by a second stir weld.

14 . The engine of claim 13 , wherein the first cover and the second cover define a central portion of a suction sidewall.

15 . The engine of claim 14 , wherein the airfoil further comprises:
a third cover portion stir welded to the cover mounting support and to the first and second cover portions, the third cover portion bridging the first and second cover portions which together define the central portion of the airfoil sidewall.

16 . The engine of claim 13 , wherein the cover mounting support comprises:
a spanwise rib extending from a root side to a tip side of the recess, the spanwise rib separating the recess into a forward portion and an aft portion.

17 . The engine of claim 16 , wherein the cover mounting support comprises:
a plurality of spaced apart spanwise ribs.

18 . The engine of claim 15 , further comprising:
a plurality of curved reinforcement ribs disposed in at least one of the forward portion and the aft portion of the recess.

19 . The engine of claim 18 , further comprising:
a porous material disposed between individual ones of the plurality of reinforcement ribs.

20 . A method of making an airfoil, the method comprising:
providing an airfoil body with a solid perimeter portion surrounding a recess and a cover mounting support extending through the recess; engaging a first cover piece with a first edge of the recess; engaging a second cover piece with a second edge of the recess opposite the first edge; and joining at least the first cover piece and the second cover piece to the cover mounting support by at least one stir weld.

21 . The method of claim 20 , further comprising:
forming the recess into at least one of a suction side and a pressure side of the airfoil body.

22 . The method of claim 20 , further comprising:
bridging the first cover piece and the second cover piece with a third cover piece; and joining the third cover piece to the cover mounting support and the first and second cover pieces by at least one stir weld.

23 . The method of claim 22 , wherein the step of joining the third cover piece includes stir welding a junction of the first and second cover pieces along the cover mounting support.

24 . The method of claim 20 , wherein the cover mounting support comprises:
a spanwise rib separating the recess into a forward portion and an aft portion.

25 . The method of claim 24 , wherein the airfoil body also includes a plurality of reinforcement ribs disposed in at least one of the forward portion and the aft portion of the recess.

26 . The method of claim 24 , wherein the cover mounting support comprises:
a plurality of spaced apart spanwise ribs.

27 . The method of claim 24 , further comprising:
placing a porous material between individual ones of the plurality of reinforcement ribs.

Assignees

• United Technologies Corp

Inventors

• Schwarz Frederick M
• Weisse Michael A

Classifications

• F05D2230/239

  Inertia or friction welding · CPC title

• F02C3/04

  having a turbine driving a compressor (power transmission arrangements F02C7/36; control of working fluid flow F02C9/16) · CPC title

• B23K20/122

  using a non-consumable tool, e.g. friction stir welding · CPC title

• B23K2101/001

  Turbines · CPC title

• F04D29/388 Primary

  characterised by construction · CPC title