Flushing of dead legs (flexible flowline). 2

[CREAAM]

Can anyone recommend a potential flushing frequency for a dead leg line with potential for stagnant fluid causing internal corrosion (degradation of flexible flowline carcass). The line is a 6” Production Jumper- 316 SS carcass - MAOP 200 barg from well to manifold.

 

[EnergyMix]

Since no one answered this, I'll give it a shot. Is this an existing line, and have you seen corrosion? If so how long has it been between inspections? Recommendation would then be, cut the inspection time in half. If no corrosion then, go up to 3/4 of the original inspection time.

If it's a new line, but you've had experience with corrosion in similar lines, then use your experience to tell you how long to go between inspections. If you know that you find corrosion when you do inspections every 5 years (for example) do inspections at the 3 year mark. If no corrosion, then go up.

Also, flushing a dead line periodically will reduce the chance for corrosion buildup.

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[SJones]

By what mechanism are you expecting degradation of the 316? Are you indicating that the whole line is shut in for extended periods? What chemical treatment is available at the tree?

Steve Jones
Corrosion Management Consultant

http://www.linkedin.com/pub/8/83b/b04

All answers are personal opinions only and are in no way connected with any employer.

 

[CREAAM]

MIC is the concerns here. The line in question hooks-up a non-producing well to a producing one (providing the option of switching production if need be). There is scale and wax inhibitor injection.