Casing Design Safety Factors

13 May 2013 ** Update 14-May-14 ** See additional text below from Chris Sugden of Cairn Oil ***

Ladies and Gents,

The Company I am currently working for is in the process of revising their casing design manual.

The 'owner' wants to increase the 'usual' safety factors used by the industry by at least 10%.

For example, the tri-axial Burst SF has been increased from 1.25 to 1.4

His reasoning for this is that casing connection designs are not tested to more than 90% of the casing properties that they are designed for.

This is the first time I have come across this and have not seen it mentioned in any Casing Design manual I have seen.

I was wondering if anyone else has come across this rationale and seen it used in a Casing Design Manual?

It is causing much heartache as many of their current casing designs now fail and there is much 'discussion' about this line of reasoning!

Thanks in advance.

Scott
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Hi folks

I'd like to do a quick poll of the forum ..
 I want to do a quick survey of what Safety Factors Operators are using for Casing and Tubing Design.
 
Does anyone use anything different vs the list below
 
Collapse: 1.0
Burst: 1.1
Tension: 1.6
Triaxial: 1.25
 
Thanks
Chris

9 Answer(s)

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