Fracture Toughness of HSLA Coiled Tubing Used in Oil Wells Operations

2011 ◽  
Vol 134 (1) ◽  
Author(s):  
J. Wainstein ◽  
J. Perez Ipiña
Keyword(s):  
Fracture Toughness ◽  
Low Cycle Fatigue ◽  
Oil Industry ◽  
Arc Length ◽  
Cycle Fatigue ◽  
Steel Tubes ◽  
Small Thickness ◽  
Coiled Tubing ◽  
Thin Walled ◽  
Tubing Material

Coiled Tubings are thin walled steel tubes of 25–89 mm diameter and thousands meters long, used in the oil industry for production and maintenance services. They suffer plastic deformation during unwinding of the reel, passing through a goosneck arch guide and an injector unit. Strain levels are of 2–3%, making the tubing fail by low cycle fatigue in around 100 wrap–unwrap cycles. As coiled tubing material generally behaves in a ductile manner at surface and down well temperatures, the R curve has to be known to make instability analyses. J-R curves were determined to characterize the fracture toughness of nonused coiled tubing, using nonstandard specimens due to difficulties with their small thickness and diameters. Different crack lengths and crack locations were tested to analyze the 2C0/W ratio and the influence of the longitudinal weld. The R curves obtained show crack arc length dependence and are influenced by the position of the longitudinal weld.

Local damage identification of high-strength circular concrete-filled steel tubes under low cycle fatigue

2020 ◽  
pp. 105678952096320
Author(s):  
Yongtao Bai ◽  
Yanchao Yue ◽  
Yao Chen ◽  
Dong Luo ◽  
Yuhang Wang ◽  
...  
Keyword(s):  
Fatigue Life ◽  
Low Cycle Fatigue ◽  
Epistemic Uncertainty ◽  
High Strength ◽  
Cycle Fatigue ◽  
Loading History ◽  
Polymer Optical Fiber ◽  
Steel Tubes ◽  
Nonstationary Loading ◽  
Thin Walled

This paper investigates the low cycle fatigue (LCF) induced damages of high-strength circular concrete-filled steel tubular (CFT) beam-columns subjected to nonstationary loading history. The test specimens are fabricated by ultra-thin walled steel tubes with 2 mm in thickness to clarify the vulnerability concerning fatigue failure, and to evaluate the fatigue life of slender and over-design circular CFT beam-column members. Experimental results indicated that the specimens with a large D/t ratio together with thin-walled steel tubes tend to trigger highly-concentrated local buckling at column bottom where sequentially experienced premature fractures due to low cycle fatigue and the fragmentation of concrete infill. This complex LCF-induced failure mode can be identified by developing a new damage detection technique using polymer optical fiber sensors with distributed placement. It is found that the sequence of variable amplitudes during LCF history plays significant influences on the accumulation of plastic deformation which is not necessarily correlated to the sequence of nonstationary loading history induced by earthquake ground motions. Moreover, the epistemic uncertainty of variable amplitude of displacement demonstrates considerable influences on fatigue life with variable displacement amplitudes.

Characteristics of Wheel Tread for Property Improvement of Railway Wheel

2006 ◽  
Vol 326-328 ◽  
pp. 1075-1078
Author(s):  
Seok Jin Kwon ◽  
Jung Won Seo ◽  
Hyun Mu Hur ◽  
Sung Tae Kwon
Keyword(s):  
Fracture Toughness ◽  
Low Temperature ◽  
Impact Energy ◽  
Low Cycle Fatigue ◽  
Maintenance Cost ◽  
Railway Vehicle ◽  
Cycle Fatigue ◽  
Railway Wheel ◽  
Mechanics Characteristics ◽  
Wheel Material

Despite of improvement of wheel material for railway vehicle, the damages of railway wheel have been occurred in service running. Because of wheel damage with spalling, shelling and thermal crack, the maintenance cost for the railway wheel has increased. The railway wheel had standardized but the chemical composition, the mechanical property and the hardness with respect to railway wheel is merely established. In order to reduce wheel damage, it is necessary to reinforce the standard of railway wheel. In present study, the fracture mechanics characteristics of railway wheel such as low cycle fatigue, fracture toughness, impact energy depended on low temperature and so on have tested. The result shows that the standard of railway wheel has to supplement fracture toughness and impact energy depended on low temperature etc.

Fracture toughness evolution of a carbon/carbon composite after low-cycle fatigue

2019 ◽  
Vol 206 ◽  
pp. 442-451 ◽  
Author(s):  
A.A. Stepashkin ◽  
D.Yu. Ozherelkov ◽  
Yu.B. Sazonov ◽  
A.A. Komissarov
Keyword(s):  
Fracture Toughness ◽  
Low Cycle Fatigue ◽  
Carbon Composite ◽  
Cycle Fatigue

Latest Development in Physics-Based Modeling of Coiled Tubing Plasticity and Fatigue

SPE Journal ◽  
2021 ◽  
pp. 1-12
Author(s):  
Zhanke Liu ◽  
Steven Tipton ◽  
Dinesh Sukumar
Keyword(s):  
Damage Accumulation ◽  
Low Cycle Fatigue ◽  
Experimental Investigations ◽  
Cycle Fatigue ◽  
State Variables ◽  
Coiled Tubing ◽  
Wall Thinning ◽  
Fatigue Damage Accumulation ◽  
Wide Range ◽  
Novel Algorithms

Summary Coiled tubing (CT) integrity is critical for well intervention operations in the field. To monitor and manage tubing integrity, the industry has developed a number of computer models over the past decades. Among them, low-cycle fatigue (LCF) modeling plays a paramount role in safeguarding tubing integrity. LCF modeling of CT strings dates back to the 1980s. Recently, novel algorithms have contributed to developments in physics-based modeling of tubing fatigue and plasticity. When CT trips into and out of the well, it goes through bending/straightening cycles under high differential pressure. Such tough conditions lead to low- or ultralow-cycle fatigue, limiting CT useful life. The model proposed in this study is derived from a previous one and is based on rigorously derived material parameters to compute the evolution of state variables from a wide range of loading conditions. Through newly formulated plasticity and strain parameters, a physics-based damage model predicts CT fatigue life, along with diametral growth and wall thinning. The revised modeling approach gives results for CT damage accumulation, diametral growth, and wall thinning under realistic field conditions, with experimental validation. For 20 different CT alloys, it was observed that the model improved in accuracy overall by approximately 18.8% and consistency by 14.0%, for constant pressure data sets of more than 4,500 data points. The modeling results provide insights into the nonlinear nature of fatigue damage accumulation. This study allowed developing recommendations to guide future analytical modeling and experimental investigations, summarize theoretical findings in physics-based LCF modeling, and provide practical guidelines for CT string management in the field. The study provides a fundamental understanding of CT LCF and introduces novel algorithms in plasticity and damage.

Latest Development in Physics-Based Modeling of Coiled Tubing Plasticity and Fatigue

2021 ◽  
Author(s):  
Zhanke Liu ◽  
Steven M. Tipton ◽  
Dinesh Sukumar
Keyword(s):  
Damage Accumulation ◽  
Low Cycle Fatigue ◽  
Experimental Investigations ◽  
Cycle Fatigue ◽  
State Variables ◽  
Coiled Tubing ◽  
Wall Thinning ◽  
Fatigue Damage Accumulation ◽  
Wide Range ◽  
Novel Algorithms

Abstract Coiled tubing (CT) integrity is critical for well intervention operations in the field. To monitor and manage tubing integrity, the industry has developed a number of computer models over the past decades. Among them, low-cycle fatigue (LCF) modeling plays a paramount role in safeguarding tubing integrity. LCF modeling of CT strings dates back to the 1980s. Recently, novel algorithms have contributed to developments in physics-based modeling of tubing fatigue and plasticity. As CT trips into and out of the well, it goes through bending-straightening cycles under high differential pressure. Such tough conditions lead to low- or ultralow-cycle fatigue, limiting CT useful life. The model proposed in this study is derived from a previous one and based on rigorously derived material parameters to compute the evolution of state variables from a wide range of loading conditions. Through newly formulated plasticity and strain parameters, a physics-based damage model predicts CT fatigue life, along with diametral growth and wall thinning. The revised modeling approach gives results for CT damage accumulation, diametral growth, and wall thinning under realistic field conditions, with experimental validation. For 20 different coiled tubing alloys, it was observed that the model improved in accuracy overall by about 18.8% and consistency by 14.0%, for constant pressure data sets of more than 4,500 data points. The modeling results provide insights into the nonlinear nature of fatigue damage accumulation. This study allowed developing recommendations to guide future analytical modeling and experimental investigations, to summarize theoretical findings in physics-based LCF modeling, and to provide practical guidelines for CT string management in the field. The study provides a fundamental understanding of CT LCF and introduces novel algorithms in plasticity and damage.

scholarly journals Improvement of Fracture Toughness and Low-Cycle Fatigue Life for INCONEL718 Welded Joint in the LE-7 Rocket Engine Main Injector.

1995 ◽  
Vol 61 (588) ◽  
pp. 1707-1712 ◽  
Author(s):  
Keiichi Hasegawa ◽  
Kiyoshi Ando ◽  
Shouji Kitade ◽  
Mitsumasa Sakamoto ◽  
Yukio Fukushima ◽  
...  
Keyword(s):  
Fracture Toughness ◽  
Fatigue Life ◽  
Welded Joint ◽  
Low Cycle Fatigue ◽  
Rocket Engine ◽  
Cycle Fatigue
Sign in / Sign up

Export Citation Format

Share Document