Test bench combining high-frequency tribological stress and oligocyclic fatigue

Patent metadata

Field	Value
Publication number	US-2016116387-A1
Application number	US-201414890831-A
Country	US
Kind code	A1
Filing date	May 9, 2014
Priority date	May 17, 2013
Publication date	Apr 28, 2016
Grant date	—

Abstract

Test rig combining high-frequency tribological stress and low-cycle fatigue, comprising a first test piece which is fixed to a frame and defines at least one bearing surface, a second test piece which is connected to traction means for loading the second test piece so that it bears against the or each bearing surface of the first test piece, means for heating the test pieces and means for loading the test pieces in a vibratory manner so as to carry out a fretting fatigue and low-cycle and high-cycle fatigue test, one of the test pieces comprising a portion which is in the shape of a turbine engine rotor blade root and which is inserted in a groove, the shape of which groove is substantially complementary to the other test piece so as to reproduce a turbine engine blade-disc attachment.

First claim

1 . Test rig combining high-frequency tribological stress and low-cycle fatigue, comprising a first test piece which is fixed to a frame and defines at least one bearing surface, and a second test piece which is connected to traction means for loading the second test piece so that it bears against the at least one bearing surface of the first test piece and carrying out a low-cycle fatigue test, one of the test pieces comprising a portion which is in the shape of a turbine engine rotor blade root and is inserted in a groove, the shape of which groove is substantially complementary to the other test piece so as to reproduce a turbine engine blade-disc attachment, the rig further comprising means for heating the test pieces and means for loading the test pieces in a vibratory manner so as to carry out a fretting fatigue test, and wherein it comprises means for adjusting the position of the test pieces around an axis which is parallel to the tensile axis, and means for locking said test pieces in a position around said axis, the adjustment and locking means being capable of adjusting the loading direction.

2 . Test rig according to claim 1 , wherein the heating means make it possible to heat the test pieces to a temperature of approximately 800° C.

3 . Test rig according to claim 1 , wherein it is configured in such a way that the portion in the shape of a blade root of one of the test pieces and the groove in the other test piece are located in an antinode of a first vibration mode of the rig.

4 . Test rig according to claim 1 , wherein the portion ( 112 ) in the shape of a blade root has a shape and dimensions which are similar to those of an actual turbine engine rotor blade.

5 . Test rig according to claim 1 , wherein the loading means comprise a shaker which loads a portion of the rig to a frequency of approximately 2000 Hz.

6 . Test rig according to claim 1 , wherein one of the test pieces is connected to the frame ( 108 ) by an I-shaped part ( 120 ) having a flexible middle portion, and the other test piece is connected to the traction means by another I-shaped part having a flexible middle portion.

7 . Test rig according to claim 6 , wherein the adjustment and locking means comprise screws which are likewise used to fix the test pieces to the I-shaped parts.

8 . Test rig according to claim 1 , wherein the portion ( 112 ) in the shape of a blade root is of the dovetail or fir-tree type.

9 . Method for using a rig for fretting fatigue and fatigue tests, said test rig comprising a test piece which is connected to traction means and comprises a portion which is in the shape of a turbine engine rotor blade root, and another test piece which is fixed to a frame and comprises a groove for receiving said portion in the shape of a blade root, said groove being substantially complementary to said portion and defining at least one bearing surface of said portion, comprising: simultaneously subjecting the two test pieces to heating and to tensile and vibratory stresses for a fretting fatigue and low-cycle and high-cycle fatigue test, wherein it comprises, before said simultaneously subjecting the two test pieces to heating and to tensile and vibratory stresses adjusting and locking the position of the test pieces around an axis which is parallel to the tensile axis.

Assignees

• Turbomeca
• Snecma

Inventors

• Houze Laurent
• Lapuyade Jean Philippe
• Vernis Franck
• Vogel François
• Meriaux Jean Vincent Manuel

Classifications

• G01N2203/0226

  High temperature; Heating means · CPC title

• G01N2203/0073

  Fatigue · CPC title

• G01N2203/0005

  Repeated or cyclic · CPC title

• G01N2203/027

  Specimens with holes or notches · CPC title

• G01N3/32 Primary

  by applying repeated or pulsating forces · CPC title