Which alloys can be used in gas extraction and purification plants?
Duplex Stainless Steel- Austenitic Ferritic stainless steels were initially made for use in the paper plants to prevent corrosion problems due to chloride bearing cooling water and other aggressive chemical process fluids. Containing high concentration of chromium, nitrogen, and molybdenum, these steel materials provide supreme resistance to localized and uniform corrosion. Their duplex structure introduces good mechanical strength, good abrasion, erosion and fatigue resistance.
Super Duplex Stainless Steel
Super Duplex Stainless steel is popular for offering outstanding resistance to acid chlorides, acids, caustic solutions and other harsh conditions.
Standard applications of super duplex stainless steel are:
- Desalination plants
- Heat exchangers
- Pollution control
- Pulp and paper plants
- Tube and pipe systems for petrochemical refineries
Alloy 400 is a nickel-copper alloy offering high resistance to marine water and steam at high temperatures, salt and caustic solutions. It offers supreme resistance in a wide range of environments and is also features by excellent welability and medium to high strength.
Monel 400 has been widely used in diverse applications for its superior resistance to quickly running brackish water or marine water. It is specifically resistant to hydrochloric and hydrofluoric acids. Alloy 400 is commonly used in chemical, oil and marine plants. Good mechanical properties from sub-zero temperatures to 1020oF.
General applications of Monel 400 are:
- Valves, pumps, shafts, fittings and fasteners particularly in marine media
- Chemical and hydrocarbon processing units
- Gasoline and freshwater tanks
- Seawater handling components
Incoloy Alloy 825
Alloy 825 is a nickel-iron-chromium alloy with inclusions of molybdenum, copper and titanium. It is made to offer supreme resistance to diverse corrosive conditions. Incoloy 825 offers resistance to various acids and alkalis in both oxidizing and reducing conditions such as sulphuric, sulphurous, phosphoric, nitric and organic acids like sodium or potassium hydroxide and aqueous chloride solutions. It contains nickel in high concentration to prevent stress corrosion cracking and pitting and crevice corrosion.
Incoloy 825 is a versatile general engineering alloy that prevents mechanical characteristics at room and high temperatures. It is commonly used in chemical processing, pollution control, oil and gas recovery, acid development and nuclear fuel reprocessing.
It offers supreme resistance to pitting and crevice corrosion and has good resistance to intergranular corrosion. It is almost resistance to chloride induced stress corrosion cracking. With these characteristics the alloy has great resistance to corrosion by a wide range of media including nitric, phosphoric, sulphuric and hydrochloric acids and alkalis and organic acids in oxidizing and reducing conditions. Alloy Inconel 625 wire is virtually resistant to corrosion in marine and industrial atmospheres with great resistance to seawater even at high temperatures.
Alloy 625 is a great choice for applications where high corrosion-fatigue strength, high tensile strength, creep and rupture strength and good weldability are needed.
Standard applications of Incoloy 625
This alloy offers supreme resistance to pitting and crevice corrosion and prevents intergranular attack. It is fully resistant to chloride induced stress corrosion cracking. With these characteristics this alloy offers good resistance to corrosion in a wide range of media and media such as nitric, phosphoric, sulfuric and hydrochloric acids. Alloy 625 is one of the most used materials in sour gas service.