BENEFITS of 6% MOLY
- High resistance to pitting, crevice and general corrosion.
- Very high resistance to chloride stress corrosion cracking.
- 50% stronger than 300-series austenitic stainless steels.
- Excellent impact toughness.
- Excellent workability and weldability.
6% MOLY APPLICATIONS
- Seawater handling equipment; heat exchanger, cooling water pipes
- Pulp mill bleach systems; drums, vats and press rolls.
- Tall oil distillation columns and equipment
- Chemical processing equipment
- Food processing equipment
- Desalination equipment
- Flue gas desulphurization scrubbers
- Oil and gas production equipment
- Tanks and pipelines for various chemicals with high halide levels
UNS S32760, UNS S31803, UNS S32750, UNS S31254
UNS S32154 is austenitic 6% molybdenum Super Duplex stainless steel used
widely in seawater cooled power plant condensers.
The first high-performance austenitic stainless steel designed
specifically to use nitrogen for added corrosion resistance, S31254 has a superior resistance to chloride pitting, crevice corrosion
and stress corrosion cracking, especially in water that contains
Uses of UNS S31254 include condenser tubes, heat exchange tubes, tubesheets and
service water piping in nuclear power plants.
UNS S32760 is a Super Duplexstainless steel equivalent to A182 F55 with a microstructure of 50:50 austenite and ferrite. The high
chromium and molybdenum content of Super Duplex makes S32760 extremely resistant to uniform corrosion by both organic and
inorganic acids – especially those containing chloride.
The higher than average molybdenum and chromium content also gives UNS S32760 greater heat resistance quality and is also designed, as a Super
Duplex alloy stainless steel, to feature high tensile & yield
strength, pitting resistance, strong weldability, resistance to
stress corrosion cracking, erosion & crevice corrosion and
corrosion fatigue and good toughness.
UNS S32760 is used in equipment for the oil & gas industry, on offshore
platforms, in heat exchangers, chemical processing, pressure
vessels and boilers as well as in the petrochemical industry and
desalination plants, including seawater piping.
UNS S32750 is the most common Super Duplex grade, equivalent to A182 F53, combining high tensile and impact strength, with a low
co-efficience for thermal expansion and a high thermal
The high chromium (25%), molybdenum (4%) and nitrogen levels
provide excellent resistance to pitting, crevice and general
corrosion, meaning that UNS S32750 is designed for use in demanding applications which require
exceptional strength and corrosion resistance such as chemical
process, petrochemical and offshore platforms and seawater
Other uses of S32750 include heat exchangers, pressure vessels and boilers,
fire-fighting systems, desalination plants, high pressure RO-plant
and seawater piping, absorber towers, ducting & piping and
power industry FGD systems.
UNS S32750 also contains excellent mechanical properties, meaning that a
light gauge of S32750 can be used to achieve the same design strength of a thicker
nickel alloy – saving both weight and overall cost of fabrication.
UNS S31803 is a Duplex stainless steel equivalent to A182 F51 (1.4462) created as a austenitic ferretic iron chromium-nickel
alloy with molybdenum addition.
Designed to combine improved resistance to stress corrosion
cracking, pitting and crevice corrosion, S31803 is roughly double the strength of standard austenitic stainless
steel. This means that UNS S31803 can be used successfully as an alternative to standard stainless
steel specifications where a higher strength and higher stress
corrosion resistance is required.
As Duplex material, UNS S31803 offers the benefits of high strength and corrosion resistance as
well as low thermal expansion, higher heat conductivity than
austenitic steels, high energy absorption and good workability and
Uses of UNS S31803 include forged or rolled alloy steel pipe flanges, primarily for
the petrochemical industry, forged fittings and valves for high
temperature application, heat exchangers, chemical tanks,
refineries, compressor parts for seawater desalination plants and
offshore pressure vessel parts.