Resistance of cemented concentric casing strings under nonuniform loading

Journal Article · Sun Mar 01 04:00:00 EST 1992 · SPE (Society of Petroleum Engineers) Drilling Engineering; (United States)

DOI:https://doi.org/10.2118/17927-PA· OSTI ID:5651529

El-Sayed, A A.H.; Khalaf, F ^[1]

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1. Cairo Univ. (EG)

This paper discusses the case of two opposing unidirectional collapse loads uniformly distributed along the diameter of a single casing string and two cemented concentric casing strings. The stress distribution in the casing and cement and the deformation of the pipe are determined by adapting known solutions in the mathematical theory of elasticity to the problem of single- and dual-casing strings subjected to this type of loading. Results were obtained for the case of uniform hydrostatic radial collapse loads for the two casing sizes (9 5/8 and 7 in.) and their cemented structures. The resistance of the single pipe to this type of nonuniform loading may drop to 11% of its design resistance to uniform hydrostatic collapse pressure. The resistance of the cemented concentric strings under uniform and nonuniform loads is about the sum of the steel pipe resistances under the same conditions. The paper also includes the superposition of uniform and nonuniform collapse loads and the practical implications of these results. The authors conclude that nonuniform loading should be considered in casing design, especially opposite salt formations.

• OSTI ID: 5651529
• Journal Information: SPE (Society of Petroleum Engineers) Drilling Engineering; (United States), Journal Name: SPE (Society of Petroleum Engineers) Drilling Engineering; (United States) Vol. 7:1; ISSN 0885-9744; ISSN SDENE
• Country of Publication: United States
• Language: English

Related Subjects

02 PETROLEUM
020300* -- Petroleum-- Drilling & Production
03 NATURAL GAS
030300 -- Natural Gas-- Drilling
Production
& Processing
CEMENTING
DEFORMATION
DESIGN
PIPES
STRESS ANALYSIS
WELL CASINGS