SPE Drilling & Completion
Volume 24,
Number 1,
March 2009,
pp. 89-95
Introduction
The design and development of steam-injection fields is a mature subject.
Because the tubulars in these wells invariably experience inelastic loading,
issues such as the effects of temperature on the static and cyclic (fatigue)
material properties become important. The original papers that address
steam-injection casing-design issues date back to the 1960s. These studies
include temperature prediction (Leutwyler and Bigelow 1965), casing-stress
analysis (Willhite and Dietrich 1967), and development of design guidelines
(Holliday 1969). Though these works acknowledge the role of temperature on the
static and cyclic material properties, data on the cyclic thermal properties of
oil-country tubular-goods steels rarely appear in oilfield literature (Placido
et al. 1997; Maruyama et al. 1990).
This paper presents a mathematical model of casing strings subjected to
thermal loads in steam-injection wells. The model includes the effects of
temperature on material properties and the effects of wellbore curvature and
prestress during the heating cycle. Several counterintuitive aspects of the
casing-stress state during cooling/unloading are examined. Further, the general
equations are shown, with appropriate simplifications, to reproduce the earlier
work (Willhite and Dietrich 1967; Holliday 1969). Example calculations are used
throughout to illustrate key insights.
© 2009. Society of Petroleum Engineers
View full textPDF
(
854 KB
)
History
- Original manuscript received:
20 November 2006
- Meeting paper published:
20 February 2007
- Revised manuscript received:
14 October 2008
- Manuscript approved:
17 October 2008
- Published online:
16 March 2009
- Version of record:
1 March 2009
View Cart
