Transgranular Stress Corrosion Cracking

Transgranular Stress

Corrosion CrackingMUHAMMAD ARIF SAADILAH

1406507285

Layout

Definition

Characteristics

Factors

Corrosion

Crack

Mechanism

Study Case 1

Definition

Factors Specific Crystal Planes

Low Indices: [100], [110], [210]

Speciffic Electrochemical

Cracking Mechanism

Characteristics of SCC

Corrosion type: Pitting

Prevention

Lowering the stress

Eliminating the critical environmental species

Adding Inhibitors

Coatings

Changing the material

Shot-peening / Shot Blasting

Applying cathodic protection

Study Case

Stress corrosion cracking of sensitized

austenitic stainless steels in Kuwait

petroleum refineriesAlmubarak and M. Belkharchouche & A. Husain

Anti-Corrosion Methods and Materials

Volume 57 · Number 2 · 2010 · 58–64

Case Study: Stress corrosion cracking of sensitized

austenitic stainless steels in Kuwait

petroleum refineries – Introduction -

Austenite

- H2S

- Sour Gas

- Polythionic Acid

Kuwait

Petroleum Reinaries

Case Study: Stress corrosion cracking of sensitized

austenitic stainless steels in Kuwait

petroleum refineries

– Materials-

• Annealed by 1080 C, thn

water quenching

• Sensitizing heat 650 C then

air cooling

Case Study: Stress corrosion cracking of sensitized

austenitic stainless steels in Kuwait

petroleum refineries – Methods-

Case Study: Stress corrosion cracking of sensitized

austenitic stainless steels in Kuwait petroleum refineries

– Results-

• Sensitized austenitic stainless steel type 304 in polythionic acid

• sensitized austenitic stainless steel type 304 in sour

solution

Case Study: Stress corrosion cracking of sensitized

austenitic stainless steels in Kuwait

petroleum refineries – Results-

sensitized austenitic stainless steel type 304 in chloride solution

Case Study: Stress corrosion cracking of sensitized

austenitic stainless steels in Kuwait

petroleum refineries – Results-

Case Study: Stress corrosion cracking of sensitized

austenitic stainless steels in Kuwait

petroleum refineries – Results-

a) Sensitized austenitic stainless steel type 321 in polythionic acid;

b) sensitized austenitic stainless steel type 321 in sour solution;

c) sensitized austenitic stainless steel type 321 in chloride solution;

Case Study: Stress corrosion cracking of sensitized

austenitic stainless steels in Kuwait

petroleum refineries – Results-

Case Study: Stress corrosion cracking of sensitized

austenitic stainless steels in Kuwait

petroleum refineries – Result-

the polythionic acid is the primary contributory agent for cracking

Types 304 and 316 stainless steel are unsuitable for longterm

exposure in sulfide service above 4008C because of sensitization.

sensitization evidently accelerates SCC and causes cracking to

occur easily

The present investigation was done in a short period (45 days)

for different grades of sensitized stainless steel where cracking and

severe SCC occurred.

Case Study: Stress corrosion cracking of sensitized

austenitic stainless steels in Kuwait

petroleum refineries – Conclusion-

Terima Kasih