API Standard 6A718 Inclusion of Additional Alloy 718 Strength Classes –

June Update

Acceptance of alloy 718 at 140 ksi min yield strength

Rashmi BhavsarGlobal Materials Métier Manager Schlumberger June 2012

Agenda

• Background• Inclusion of 718 -140 • Corrosion testing

Inclusion of Additional Alloy 718 Strength Classes

Background•718 -120 ksi - API Standard 6A718, 1st and 2nd Editions•718-140 ksi - need for inclusion•Heat treatment and microstructure discussed last meeting

Mechanical Properties

Inclusion of Additional Strength Level

•The 140 KSI grade cannot simply be added in this manner. It will require aging temperature to be changed from 1425 - 1475 F to 1400 -1475 F for 140 grade. •The yield strength range will be 140 to 150 ksi (the current spec limits the yield strength to 145 ksi max for 120 grade)•40HRc max remain for now (Future 43 HRc max – NACE approval will require)

Initial Ballots

• A Ballot in 1982 from various suppliers and Shell Development to change hardness to 40HRC max

• Hardness up to 45HRc and YS up to 165 ksi • Most data were at 750 and 1670F

Recent Testing

144 ksi actual yield strength at room temp – 100% stress level for six months

Courtesy: Foroni Metals

Testing also successful at extremely high H2S/CO2 at 350 and 450 F – No cracks

(30 days test)

Courtesy : Schlumberger

500 Psi H2S, 500 psi CO2, 25%NaCl at 500oF

Validation Testing • With 40 HRc Max per Current MR0175 – min 3 heats

– Perform 90 days four point bent beam or c-ring Or Perform 30/90 days creviced bent beam or c-ring – Perform SSRT in duplicates for information and ranking

– Test 140 and 150 ksi actual yield strength – Test environment

• NACE level 6 (500 psi H2S, 500 CO2 and 121,300 mg/l cl at ) 350F) Or • H2S per NACE limits at 350F

Approximate cost $90 to 100K

Feedback from Corrosion 2012

• Supported the validation testing idea • Testing required for Hydrogen Embrittlement– Recommendation for SSRT with hydrogen charging by

Total

or – perform alternate testing - Uniaxial notched tensile

test with hydrogen charging

• Testing procedure information being collected. • Higher temperature testing recommended

Corrosion Testing being Considered

• Test 718-140 ksi(actual close to 150 ksi) along with 718-120 ksi (actual 140 ksi ) • Perform 90 days 3” C-ring in duplicate from 3

suppliers min. (possibly 5) H2S-500 psi, CO2-1000 psi, Cl -180,000 ppm at 400F• SSRT – the same environment • Hydrogen embrittlement test – TBD

• Quotes from three labs to be collected