Track-4-Ben-Verhagen - Validation of ASME 31G and RSTRENG
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Transcript of Track-4-Ben-Verhagen - Validation of ASME 31G and RSTRENG
VALIDATON OF THE ASME B31G AND RSTRENG
METHODOLOGIES FOR THE DETERMINATION OF THE
BURST PRESSURE OF CORRODED PIPES IN API 5L X70 / EN
10208-2 L485
Frédéric Dewint, AIBFrédéric Dewint, AIB--Vinçotte InternationalVinçotte International
33rdrd ASME India Oil & Gas Pipeline Conference, 2011, February 3ASME India Oil & Gas Pipeline Conference, 2011, February 3--5, Goa, India5, Goa, India
CONTENTS
• OBJECTIVES OF THE STUDY
• FAILURE PRESSURE ACCORDING ASME B31G AND RSTRENG
• TEST PROGRAM
- Burst tests
- Strain gauge measurements
- Calculations in accordance with ASME B31G and RSTRENG
- Linear and Nonlinear Finite Element Calculations
• CONCLUSIONS
VALIDATION OF THE ASME B31G AND THE RSTRENG VALIDATION OF THE ASME B31G AND THE RSTRENG
METHODOLOGIES FOR PIPE MATERIAL X70 / L485METHODOLOGIES FOR PIPE MATERIAL X70 / L485
VALIDATION OF THE ASME B31G AND THE RSTRENG VALIDATION OF THE ASME B31G AND THE RSTRENG
METHODOLOGIES FOR PIPE MATERIAL X70 / L485METHODOLOGIES FOR PIPE MATERIAL X70 / L485
REMARK
The study was performed in collaboration between
AIB-Vinçotte International (www.vincotte.com)
Fluxys (www.fluxys.com)
Labo Soete of the Ghent University (www.tribology-fatigue.ugent.be)
VALIDATION OF THE ASME B31G AND THE RSTRENG VALIDATION OF THE ASME B31G AND THE RSTRENG
METHODOLOGIES FOR PIPE MATERIAL X70 / L485METHODOLOGIES FOR PIPE MATERIAL X70 / L485
OBJECTIVES OF THE STUDY
• Validate ASME B31G and RSTRENG methodologies on pipe in X70 / L485 material with supplementary requirements related to :
- ratio yield strength / tensile strength
- impact testing at –20°C
• Demonstrate the real safety margin of corroded high pressure gaspipelines in X70 / L485 against bursting under internal pressureloading.
• Assess the capability of Finite Element calculations for predicting the failure pressure of corroded pipes and in a further step thefailure pressure of corroded fitings.
VALIDATION OF THE ASME B31G AND THE RSTRENG VALIDATION OF THE ASME B31G AND THE RSTRENG
METHODOLOGIES FOR PIPE MATERIAL X70 / L485METHODOLOGIES FOR PIPE MATERIAL X70 / L485
ASME B31G & RSTRENG
• The ASME B31G and RSTRENG methodologies are used for the determination of the remaining strength of externally corroded pipe subjected to internal pressure loading.
• Both methodologies modelize defects by their depth d and by their length L in the longitudinal direction. The defect width w is not considered explicitly in the calculation.
• RSTRENG allows to take into account more accurately the corrosion defect geometry.
VALIDATION OF THE ASME B31G AND THE RSTRENG VALIDATION OF THE ASME B31G AND THE RSTRENG
METHODOLOGIES FOR PIPE MATERIAL X70 / L485METHODOLOGIES FOR PIPE MATERIAL X70 / L485
LIMITATIONS
• Limited to corrosion on weldable pipeline steels categorized as carbon steels or high strength low alloy steels.
• Do not apply to welds except to corrosion anomalies in submerged arc seam welds.
• Defects caused by mechanical damage, such as gouges and grooves, are prohibited.
• Limited to anomalies having depths lower than 80 percent of the wall thickness.
• Limited to defects which have relatively smooth contours and cause low stress concentrations (e.g. electrolytic or galvanic corrosion, loss of wall thickness due to erosion).
• Only internal pressure loading is considered.
VALIDATION OF THE ASME B31G AND THE RSTRENG VALIDATION OF THE ASME B31G AND THE RSTRENG
METHODOLOGIES FOR PIPE MATERIAL X70 / L485METHODOLOGIES FOR PIPE MATERIAL X70 / L485
ASME B31G CALCULATION METHOD
failure pressure is Pfail = 2 x Sfail x t / D with :
D : diameter of the pipe
t : wall thickness of the pipe
Sfail : failure stress = S (1-A/Ao)/[1-(A/Ao)(MT-1)]
S : flow stress = 1.1 SMYS
A : defect area in the longitudinal plane through the wall thickness ; B31G considers A = (2/3) d L
Ao : is L t
MT : two-term Folias factor ; f(L, Dt)
L : axial extent of the defect
d : maximum defect depth
VALIDATION OF THE ASME B31G AND THE RSTRENG VALIDATION OF THE ASME B31G AND THE RSTRENG
METHODOLOGIES FOR PIPE MATERIAL X70 / L485METHODOLOGIES FOR PIPE MATERIAL X70 / L485
RSTRENG CALCULATION METHOD
failure pressure is Pfail = 2 x Sfail x t / D with :
D : diameter of the pipe
t : wall thickness of the pipe
Sfail : failure stress = S (1-A/Ao)/[1-(A/Ao)(MT-1)]
S : flow stress = SMYS + 10 ksi = SMYS + 69 MPa
A : defect area in the longitudinal plane through the wall thickness ; if no detailed analysis, i.e. : 0.85 d L
Ao : is L t
MT : three-term Folias factor ; f(L, Dt)
L : axial extent of the defect
d : maximum defect depth
VALIDATION OF THE ASME B31G AND THE RSTRENG VALIDATION OF THE ASME B31G AND THE RSTRENG
METHODOLOGIES FOR PIPE MATERIAL X70 / L485METHODOLOGIES FOR PIPE MATERIAL X70 / L485
TEST PROGRAM
• To demonstrate the validity of the ASME B31G and RSTRENG methodologies for pipe material X70/L485, a test program was defined by Vinçotte in collaboration with Fluxys and the Laboratory Soete of Ghent University :
- burst testing of the test pieces with artificial defects
- comparison with failure pressure from ASME B31G & RSTRENG
- comparison with failure pressure calculated by finite element method
- comparison of strain gauge measurements with the strains from finite element calculations
VALIDATION OF THE ASME B31G AND THE RSTRENG VALIDATION OF THE ASME B31G AND THE RSTRENG
METHODOLOGIES FOR PIPE MATERIAL X70 / L485METHODOLOGIES FOR PIPE MATERIAL X70 / L485
TEST PIECE PARAMETERS
VALIDATION OF THE ASME B31G AND THE RSTRENG VALIDATION OF THE ASME B31G AND THE RSTRENG
METHODOLOGIES FOR PIPE MATERIAL X70 / L485METHODOLOGIES FOR PIPE MATERIAL X70 / L485
TEST PIECE 4 drawing
VALIDATION OF THE ASME B31G AND THE RSTRENG VALIDATION OF THE ASME B31G AND THE RSTRENG
METHODOLOGIES FOR PIPE MATERIAL X70 / L485METHODOLOGIES FOR PIPE MATERIAL X70 / L485
Strain gauges installation
VALIDATION OF THE ASME B31G AND THE RSTRENG VALIDATION OF THE ASME B31G AND THE RSTRENG
METHODOLOGIES FOR PIPE MATERIAL X70 / L485METHODOLOGIES FOR PIPE MATERIAL X70 / L485
Strain gauges installation
VALIDATION OF THE ASME B31G AND THE RSTRENG VALIDATION OF THE ASME B31G AND THE RSTRENG
METHODOLOGIES FOR PIPE MATERIAL X70 / L485METHODOLOGIES FOR PIPE MATERIAL X70 / L485
TEST PIECE 1 tensile test results
VALIDATION OF THE ASME B31G AND THE RSTRENG VALIDATION OF THE ASME B31G AND THE RSTRENG
METHODOLOGIES FOR PIPE MATERIAL X70 / L485METHODOLOGIES FOR PIPE MATERIAL X70 / L485
TEST PIECE 1 impact test results – 2 o’ clock
VALIDATION OF THE ASME B31G AND THE RSTRENG VALIDATION OF THE ASME B31G AND THE RSTRENG
METHODOLOGIES FOR PIPE MATERIAL X70 / L485METHODOLOGIES FOR PIPE MATERIAL X70 / L485
3D model
VALIDATION OF THE ASME B31G AND THE RSTRENG VALIDATION OF THE ASME B31G AND THE RSTRENG
METHODOLOGIES FOR PIPE MATERIAL X70 / L485METHODOLOGIES FOR PIPE MATERIAL X70 / L485
TP1 : DN600 tactual = 11.3 mm Pdesign = 80 bar
Defect 3 : L = 210 mm d = 4.1 mm w = 100* mm
Actual Burst Pressure : 214 Bar
ASME B31G : 166 bar RSTRENG : 164 bar FEM-NL : 175 bar
VALIDATION OF THE ASME B31G AND THE RSTRENG VALIDATION OF THE ASME B31G AND THE RSTRENG
METHODOLOGIES FOR PIPE MATERIAL X70 / L485METHODOLOGIES FOR PIPE MATERIAL X70 / L485
TP2 : DN600 tactual = 11.4 mm Pdesign = 80 bar
Defect 2 : L = 200 mm d = 6.8 mm w = 128 mm
Actual Burst Pressure : 150 bar
ASME B31G : 143 bar RSTRENG : 133 bar FEM-NL : 83 bar
VALIDATION OF THE ASME B31G AND THE RSTRENG VALIDATION OF THE ASME B31G AND THE RSTRENG
METHODOLOGIES FOR PIPE MATERIAL X70 / L485METHODOLOGIES FOR PIPE MATERIAL X70 / L485
TP3 : DN900 tactual = 13.4 mm Pdesign = 84 bar
Defect 2 : L = 300 mm d = 4.0 mm w = 200 mm
Actual Burst Pressure : 173 bar
ASME B31G : 134 bar RSTRENG : 134 bar FEM-NL : 125 bar
VALIDATION OF THE ASME B31G AND THE RSTRENG VALIDATION OF THE ASME B31G AND THE RSTRENG
METHODOLOGIES FOR PIPE MATERIAL X70 / L485METHODOLOGIES FOR PIPE MATERIAL X70 / L485
TP4 : DN900 tactual = 13.4 mm Pdesign = 84 bar
Defect 1 : L = 300 mm d = 6.0 mm w = 600 mm
Actual Burst Pressure : 133 bar
ASME B31G : 122 bar RSTRENG : 118 bar FEM-NL : 97 bar
VALIDATION OF THE ASME B31G AND THE RSTRENG VALIDATION OF THE ASME B31G AND THE RSTRENG
METHODOLOGIES FOR PIPE MATERIAL X70 / L485METHODOLOGIES FOR PIPE MATERIAL X70 / L485
RESULTS
VALIDATION OF THE ASME B31G AND THE RSTRENG VALIDATION OF THE ASME B31G AND THE RSTRENG
METHODOLOGIES FOR PIPE MATERIAL X70 / L485METHODOLOGIES FOR PIPE MATERIAL X70 / L485
Strain Gauge Measurement Results
VALIDATION OF THE ASME B31G AND THE RSTRENG VALIDATION OF THE ASME B31G AND THE RSTRENG
METHODOLOGIES FOR PIPE MATERIAL X70 / L485METHODOLOGIES FOR PIPE MATERIAL X70 / L485
Comparison strain gauge measurements / FEM
VALIDATION OF THE ASME B31G AND THE RSTRENG VALIDATION OF THE ASME B31G AND THE RSTRENG
METHODOLOGIES FOR PIPE MATERIAL X70 / L485METHODOLOGIES FOR PIPE MATERIAL X70 / L485
Test Piece 2 - defect 1 / Von Mises stresses
TP4 defect 1 - Von Mises strain : max. 1.1% at 75 bar
VALIDATION OF THE ASME B31G AND THE RSTRENG VALIDATION OF THE ASME B31G AND THE RSTRENG
METHODOLOGIES FOR PIPE MATERIAL X70 / L485METHODOLOGIES FOR PIPE MATERIAL X70 / L485
TP4 defect 1 - Von Mises strain : max. 1.8% at 82.5 bar
VALIDATION OF THE ASME B31G AND THE RSTRENG VALIDATION OF THE ASME B31G AND THE RSTRENG
METHODOLOGIES FOR PIPE MATERIAL X70 / L485METHODOLOGIES FOR PIPE MATERIAL X70 / L485
TP4 defect 1 - Von Mises strain : max. 3.2% at 90 bar
VALIDATION OF THE ASME B31G AND THE RSTRENG VALIDATION OF THE ASME B31G AND THE RSTRENG
METHODOLOGIES FOR PIPE MATERIAL X70 / L485METHODOLOGIES FOR PIPE MATERIAL X70 / L485
TP4 defect 1 - Von Mises strain : max. 5.1% at 97.5 bar
VALIDATION OF THE ASME B31G AND THE RSTRENG VALIDATION OF THE ASME B31G AND THE RSTRENG
METHODOLOGIES FOR PIPE MATERIAL X70 / L485METHODOLOGIES FOR PIPE MATERIAL X70 / L485
TP4 defect 1 - Von Mises strain : max. 23 % at 105 bar
VALIDATION OF THE ASME B31G AND THE RSTRENG VALIDATION OF THE ASME B31G AND THE RSTRENG
METHODOLOGIES FOR PIPE MATERIAL X70 / L485METHODOLOGIES FOR PIPE MATERIAL X70 / L485
VALIDATION OF THE ASME B31G AND THE RSTRENG VALIDATION OF THE ASME B31G AND THE RSTRENG
METHODOLOGIES FOR PIPE MATERIAL X70 / L485METHODOLOGIES FOR PIPE MATERIAL X70 / L485
CONCLUSIONS
• The failure pressures calculated with ASME B31G and RSTRENG method are conservative values compared with the actual bursting pressure values.
• The failure pressures calculated with the nonlinear FEM method are conservative values compared with the actual bursting pressure values.
• The failure pressures calculated with the linear FEM method are too conservative in order to be useful for practice.
• The correspondence between the strain gauge measurements and the FEM calculated strains was good in the range were measurements were possible.
• Corroded pipe in X70 / L485, as ordered in Belgian practice, has large safety margin against bursting under internal pressure.
Questions & Answers
VALIDATION OF THE ASME B31G AND THE RSTRENG VALIDATION OF THE ASME B31G AND THE RSTRENG
METHODOLOGIES FOR PIPE MATERIAL X70 / L485METHODOLOGIES FOR PIPE MATERIAL X70 / L485