Pipeline

[khaledkhezim]

Dear All:
I'm working on 6" pipeline with this environment specifications: Any idea about materials specifications?? And How? Thanks.
Environment specifications:
Temperature: 80C
H2S: 10.52 mol% which is equal to 105200 ppm
HCO3: 3 ppmw
Calculated PH: 3.834545924
GOR: 421.0941468 scf/bbl
Water Cut: 0.227467521%
Oxygen: 0 ppb
Sulfur: 10.52
Corr. Allowance: 3 mm
Pressure: 17 bar
CO2: 5.96%
Liquid Velocity: 0.945148963 m/s
Sour to NACE MR0175: YES REGION 3
Max.All. Corr. Rate: 0.15 mm/y
Corrosion Allowance: 3 mm
Designed Service Life: 20 yrs
Oil Prod Rate: 800 m3/day
Water Prod Rate: 1.823889 m3/day
Gas Prod Rate: 0.06 MMm3/day

 

[SJones]

Well, being as the material has been selected as carbon steel with 3 mm corrosion allowance, you could start with API Spec 5L, PSL2 pipe of an appropriate grade.

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.

 

[georgeverghese]

It would be good if you gave details on the gas, oil and water phase compositions for CO2 and H2S for others to advise.

In addition to compliance to NACE for sour service;
Assuming all of the 6% CO2 is in the gas phase, a CO2 partial pressure of 15psi would push this into solid duplex SS. Others more experienced in materials selection may differ, but it does look like corrosion inhibitor injection may not help much at 15psi partial pressure. CS with SS316L cladding for DN150 would be possible, but may be too much bother.

There is no information on min operating temp (due to depressurisation) - what about lower design temp influence on materials selection ?

 

[Sloss]

Everything is calculated/given to umpteen decimal places - that intrigues me a bit!