Well Integrity Technical Section

This message has been cross posted to the following Discussions: Well Integrity and Completions .
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All,

We are planning to install SCSSV in one of our well. Expected Reservoir Pressure & temperature would be 6600 psi & 330 degF, respectively. CO2 mole% would be around 9. Based on that our plan is to complete the well with Hyper (modified)13% chrome tubing. What would be the suitable metallurgy for SCSSV? to avoid galvanic or bimetallic corrosion.

Kindly share your expert opinions for suitable metallurgy selection of SCSSV... 

 

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Lajpat Rai
Petroleum Engineer
United Energy Pakistan Ltd
Karachi City
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Bimetallic corrosion is not a big issue between CRAs. 

To 'match' the tubing, you have two primary options for the primary-parts of an SCSSV :-

1. 2%Mo super-martensitic stainless steel (super-13Cr).  NACE/ISO compliant forgings, with restricted H2S tolerance, are available for accessories.
   These will tend to have less H2S tolerance than the tubing, if this is limiting, option 2 applies.
2. Age-hardened nickel alloys such as 925, 935, 945, 718.  925 is adequate.
   These should be purchased to the latest edition of API6A718 (as revised for additional alloys).

 In both cases you need to use experienced manufacturers who will be able to advise.
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Edward Wade
Metallurgical Engineer
MetalEcosse Ltd.
St Andrews, UK
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