0
Research Papers: Materials and Fabrication

Fracture Toughness of HSLA Coiled Tubing Used in Oil Wells Operations

[+] Author and Article Information
J. Wainstein, J. Perez Ipiña

GMF-LPM,  Univ. Nac. del Comahue-CONICET, Bs. As. 1400, Neuquén, Argentina

J. Pressure Vessel Technol 134(1), 011403 (Dec 20, 2011) (9 pages) doi:10.1115/1.4004569 History: Received June 05, 2010; Revised April 28, 2011; Published December 20, 2011; Online December 20, 2011

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.

FIGURES IN THIS ARTICLE
<>
Copyright © 2012 by American Society of Mechanical Engineers
Your Session has timed out. Please sign back in to continue.

References

Figures

Grahic Jump Location
Figure 6

Crack extension (2ΔC) versus displacement records. (a) Tube 1 and (b) tube 2.

Grahic Jump Location
Figure 7

Fracture surface macrograph

Grahic Jump Location
Figure 8

J-R curve for coiled tubing, tube 1

Grahic Jump Location
Figure 9

J-R curve for coiled tubing, tube 2

Grahic Jump Location
Figure 10

Fracture surfaces of four of the tested coiled tubing

Grahic Jump Location
Figure 11

J-R curves CTAs and CTBs (a) tube 1 and (b) tube 2

Grahic Jump Location
Figure 12

Stable crack growth through the longitudinal weld

Grahic Jump Location
Figure 13

CTB-4 J-R curve

Grahic Jump Location
Figure 14

CTB-5 J-R curve

Grahic Jump Location
Figure 5

Load versus load line displacement records for coiled tubing (a) tube 1 and (b) tube 2

Grahic Jump Location
Figure 4

Potential drop versus normalized arc length

Grahic Jump Location
Figure 3

Crack location with respect to longitudinal welding

Grahic Jump Location
Figure 2

Geometry of a tube with a circumferential through wall crack

Grahic Jump Location
Figure 1

Coiled tubing unit in service

Tables

Errata

Discussions

Some tools below are only available to our subscribers or users with an online account.

Related Content

Customize your page view by dragging and repositioning the boxes below.

Related Journal Articles
Related eBook Content
Topic Collections

Sorry! You do not have access to this content. For assistance or to subscribe, please contact us:

  • TELEPHONE: 1-800-843-2763 (Toll-free in the USA)
  • EMAIL: asmedigitalcollection@asme.org
Sign In