Relieved strains due to drilling hole in a ring sample cut from an autofrettage cylinder are measured. Measured strains are then transformed to residual stresses using calibration constants and mathematical relations of elasticity based on ASTM standard recommendations (American Society for Testing and Materials, ASTM E 837-08, 2008, “Standard Test Method for Determining Residual Stresses by the Hole-Drilling Strain-Gage Method,” American Society for Testing and Materials). The hydraulic autofrettage is pressurizing a closed-end long cylinder beyond its elastic limits and subsequently removing the pressure. In contrast to three-dimensional stress state in the autofrettage tube, the stress measurement in hole drilling method is performed on a traction free surface formed from cutting the ring sample. The process of cutting the ring sample from a long autofrettaged tube is simulated using finite element method (FEM) and the redistribution of the residual stress due to the cut is discussed. Hence, transformation of the hole drilling measurements on the ring slice to the autofrettage residual stresses is revealed. The residual stresses are also predicted by variable material properties (VMP) method (Jahed, H., and Dubey, R. N., 1997, “An Axisymmetric Method of Elastic-Plastic Analysis Capable of Predicting Residual Stress Field,” Trans. ASME J. Pressure Vessel Technol., 119, pp. 264–273) using real loading and unloading behavior of the test material. Prediction results for residual hoop stress agree very well with the measurements. However, radial stress predictions are less than measured values particularly in the middle of the ring. To remove the discrepancy in radial residual stresses, the measured residual hoop stress that shows a self-balanced distribution was taken as the basis for calculating residual radial stresses using field equations of elasticity. The obtained residual stresses were improved a lot and were in good agreement with the VMP solution.

References

References
1.
Withers
,
P. J.
, and
Bhadeshia
,
H. K.
, 2001, “
Residual Stress—II: Nature and Origins
,”
Mater. Sci. Technol.
,
17
, pp.
366
375
.
2.
Withers
,
P. J.
, and
Bhadeshia
,
H. K.
, 2001, “
Residual Stress—I: Measurment Techniques
,”
Mater. Sci. Technol.
,
17
, pp.
355
365
.
3.
Rendler
,
N. J.
, and
Vigness
,
I.
, 1966, “
Hole-Drilling Strain-Gage Method of Measuring Residual Stresses
,”
Exp. Mech.
,
6
, pp.
577
586
.
4.
Schajer
,
G. S.
, 1988, “
Measurement of Non-Uniform Residual Stresses Using the Hole-Drilling Method. Part I—Stress Calculation Procedures
,”
J. Eng. Mater. Technol.
,
110
, pp.
338
343
.
5.
American Society for Testing and Materials, ASTM E 837-08, 2008, “
Standard Test Method for Determining Residual Stresses by the Hole-Drilling Strain-Gage Method
,”
American Society for Testing and Materials
.
6.
Bauschinger
,
J.
, 1881, “
Ueber die Veränderung der Elasticitätsgrenze und des Elasticitätsmodulus Verschiedener Metalle
,”
Zivilingenieur
,
27
, pp.
289
348
.
7.
Stacey
,
A.
, and
Webster
,
G. A.
, 1988, “
Determination of Residual Stress Distribution in Autofrettaged Tubing
,”
Int. J. Pressure Vessels Piping
,”
31
, pp.
205
220
.
8.
Venter
,
A.
,
de Swardt
,
R.
, and
Kyriacou.
,
S.
, 2000, “
Comparative Measurements on Autofrettaged Cylinders With Large Bauschinger Reverse Yielding Zones
,”
J. Strain Anal. Eng. Des.
,
35
, pp.
459
469
.
9.
George
,
D.
, and
Smith
,
D. J.
, 2000, “
The Application of the Deep Hole Technique for Measuring Residual Stresses in an Autofrettaged Tube
,”
PVP
, Vol.
406
, pp.
25
28
.
10.
Parker
,
A. P.
, 2006, “
An Improved Method for Recovering Residual Stress From Strain Measurements in Cylinders and Rings
,”
Proceedings of PVP2006/ICPVT11, Pressure Vessel Technologies for the Global Community, American Society of Mechanical Engineers, Pressure Vessels and Piping Division (Publication)
, PVP 2006,
6
p.
11.
Underwood
,
J. H.
,
DeSwardt
,
R. R.
,
Venter
,
A. M.
,
Troiano
,
E.
,
Hyland
,
E. J.
, and
Parker
,
A. P.
, 2008, “
Hill Stress Calculations for Autofrettaged Tubes Compared With Neutron Diffraction Residual Stresses and Measured Yield Pressure and Fatigue Life
,” American Society Mechanical Engineers, Pressure Vessels Piping Division, Vol.
5
, pp.
47
52
.
12.
Schajer
,
G. S
, 1991, “
Strain Data Averaging for the Hole-Drilling Method
,”
Exp. Tech.
, pp.
25
28
.
13.
Jahed
,
H.
, and
Dubey
,
R. N.
, 1997, “
An Axisymmetric Method of Elastic-Plastic Analysis Capable of Predicting Residual Stress Field
,”
Trans. ASME J. Pressure Vessel Technol.
,
119
, pp.
264
273
.
14.
Dassault Systemes Simulia, 2010, ABAQUS/CAE™ 6.10.
15.
Kendall
,
D. P.
, 2002, “
A Short History of High Pressure Technology From Bridgman to Division 3
,”
ASME J. Pressure Vessel Technol.
,
122
, pp.
229
233
.
16.
Jahed
,
H.
, and
Ghanbari
,
G.
, 2003, “
Actual Unloading Behavior and Its Significance on Residual Stress in Machined Autofrettaged Tubes
,”
Trans. ASME J. Pressure Vessel Technol.
,
125
, pp.
321
325
.
17.
Troiano
,
E.
,
Parker
,
A.
,
Underwood
,
J.
, and
Mossey
,
C.
, 2003,
Experimental Data, Numerical Fit and Fatigue Life Calculation Relating to Bauschinger Effect in High Strength Armament Steels
,”
Trans. ASME J. Pressure Vessel Technol.
,
125
, pp.
330
335
.
18.
Jahed
,
H.
,
Ahmadi Moghadam
,
B.
, and
Shambouli
M.
, 2006, “
Re-Autofrettage
,”
Trans. ASME J. Pressure Vessels Technol.
,
128
, pp.
223
226
.
You do not currently have access to this content.