Definition of safe service use limits for use of stainless alloys in petroleum production

Book · Fri Aug 01 04:00:00 EDT 1997

OSTI ID:504754

Abayarathna, D; Kane, R D ^[1]

---

1. CLI International, Inc., Houston, TX (United States)

In this study a total of fourteen alloys from the groups of martensitic (MSS), precipitation hardened (PHSS), and duplex (DSS) stainless steels were exposed to simulated petroleum production environments containing H{sub 2}S, CO{sub 2} chloride and bicarbonate to produce a range of conditions. The particular focus of this study was the documentation of the effects of environmental and metallurgical variables on the resistance to stress corrosion cracking (SCC) and sulfide stress cracking (SSC) of these materials. Slow strain tests were also conducted in order to obtain additional information. The SCC/SSC behavior of stainless steel alloys was observed to be significantly different for conditions resulting in pH < 4.0 than for those given pH > 4.0. Buffered environments producing pH greater than 4.0 tended to be considerably less severe from the standpoint of cracking. In buffered solutions, the environmental limits for MSS and PHSS materials were 10,000 ppm Cl{sup {minus}} and 6.9 kPa (1.0 psia) H{sub 2}S. The safe use limits for coldworked DSS materials were 100,000 ppm Cl{sup {minus}} and 6.9 kPa (1.0 psia) H{sub 2}S under buffered conditions. The annealed DSS were not susceptible for SCC at 100,000 ppm Cl{sup {minus}} and up to 68.9 kPa (10 psia) H{sub 2}S under unbuffered conditions based on 30 day exposure data. The pH of the test environments had less of an affect with increasing alloy content. The tested alloys exhibited the general trend of increasing general corrosion with increasing temperature. However, the MSS alloys and some of the DSS alloys exhibited increased susceptibility to localized corrosion at 93 C than at 204 C due to the transitions from passive to active behavior or from varying passive states (i.e. oxide to sulfide).

• OSTI ID: 504754
• Report Number(s): CONF-970332--
• Country of Publication: United States
• Language: English

Related Subjects

02 PETROLEUM
36 MATERIALS SCIENCE
BRINES
CARBON DIOXIDE
CORROSION RESISTANCE
CORROSIVE EFFECTS
CRACK PROPAGATION
EXPERIMENTAL DATA
FIELD PRODUCTION EQUIPMENT
HYDROGEN SULFIDES
MATERIALS TESTING
PARAMETRIC ANALYSIS
STAINLESS STEELS
SULFIDATION