Technical Brief

Equations to Calculate Casing Collapse Strength Under Nonuniform Load Based on New ISO Model

[+] Author and Article Information
Kuanhai Deng

State Key Laboratory of Oil and Gas Reservoir Geology
and Exploitation (Southwest Petroleum University),
Sichuan 610500, China
e-mail: dengkuanhai@163.com

Yuanhua Lin

State Key Laboratory of Oil and Gas Reservoir Geology
and Exploitation (Southwest Petroleum University),
Sichuan 610500, China
e-mail: yhlin28@163.com

Wanying Liu, Dezhi Zeng

CNPC Key Lab for Tubular Goods Engineering
(Southwest Petroleum University),
Sichuan 610500, China

Yongxing Sun

Drilling & Production Engineering Technology
Research Institute (CCDC),
Sichuan 618300, China

Kewei Li

School of Geoscience and Technology,
Southwest Petroleum University,
Chengdu 610500, China

1Corresponding author.

Contributed by the Pressure Vessel and Piping Division of ASME for publication in the JOURNAL OF PRESSURE VESSEL TECHNOLOGY. Manuscript received August 23, 2015; final manuscript received March 18, 2016; published online April 29, 2016. Assoc. Editor: Hardayal S. Mehta.

J. Pressure Vessel Technol 138(5), 054501 (Apr 29, 2016) (5 pages) Paper No: PVT-15-1198; doi: 10.1115/1.4033154 History: Received August 23, 2015; Revised March 18, 2016

Many studies focused on casing collapse resistance under uniform load have been done, and API 5C3 and ISO standards have been formed. However, the collapse models presented by API 5C3 and ISO standards are not suitable for calculating and predicting the casing collapse resistance under nonuniform load (NUL), despite it is well known that the NUL has a significant impact on the casing collapse resistance. Hence, based on the elastic theory and new ISO collapse model, the conception of advance coefficient of plastic collapse of casing under NUL is put forward, and the new equations to compute casing collapse resistance under NUL are established, which takes into full account the effect of manufacturing defects (such as ovality and eccentricity) and residual stress on the casing collapse resistance. The influence rule of nonuniform coefficient of load (NCL) on casing collapse resistance has been analyzed. Numerical and experimental comparisons show that the calculation results (CR) of new equations are much closer to the real failure data than the current equations proposed by Han and EI-Sayed (1992, “Resistance of Cemented Concentric Casing Strings Under Nonuniform Loading,” SPE Drill. Eng., 7(1), pp. 59–64). Research results can provide an important theoretical reference for casing design in complicated stratum (such as plastic creep and dipping stratum).

Copyright © 2016 by ASME
Topics: Stress , Collapse
Your Session has timed out. Please sign back in to continue.



Grahic Jump Location
Fig. 1

Mechanical model of casing under NUL. (a) Hydrostatic pressure (uniform load), (b) uniform unidirectional load, and (c) NUL.

Grahic Jump Location
Fig. 2

Relationship between collapse resistance and D/t

Grahic Jump Location
Fig. 3

Relationship between the rate of decrease and D/t

Grahic Jump Location
Fig. 4

Comparison of CR with failure data

Grahic Jump Location
Fig. 5

Comparisons of CEs




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