Specification :
Super duplex stainless steel pipe, UNS S32750(SAF2507), UNS S31803(SAF2205), UNS S31500(3RE60)Overview
Super Duplex is an austenitic ferritic Iron
Chromium-Nickel alloy with Molybdenim
addition. It has good resitance to pitting,
a high tensile strength and higher resistance to stress corrosion cracking at moderate temperatures to that of conventional austenitic stainless steels.
Super Duplex is a material having an approximate equal amount of austenite and ferrite. These combine excellent corrosion resistance with high strength. Mechanical properties are approximately double those of singular austenitic steel and resistance to stress corrosion cracking is superior to type 316 stainless steel in chloride solutions. Super Duplex material has a ductile / brittle transition at approximately -50 C. High temperature use is usually restricted to a maximum temperature of 300 C for indefinite use due to embrittlement.
Benefits
There are several benefits of Duplex including:
" High Strength
" High resistance to pitting, crevice corrosion resistance
" High resistance to stress corrosion cracking, fatigue and erosion
" Excellent resistance to Chloride stress corrosion cracking
" High Thermal conductivity
" Low coefficient of thermal expansion
" Low thermal expansion and higher heat conductivity than Austenitic steels
" Good Sulfide stress corrosion resisitance
" High energy absorption
" Good workability and weldability
Super Duplex Applications
" Heat exchangers, tubes and pipes for
production and handling of gas and oil,
" Heat exchangers and pipes in desalination plants,
" Mechanical and structural components,
" Power industry FGD systems,
" Pipes in process industries handling solutions containing chlorides,
" Utility and industrial systems, rotors, fans, shafts and press rolls where the high corrosion fatigue strength can be utilized,
" Cargo tanks, vessels, piping and welding consumables for chemical tankers.
" High-strength, highly resistant wiring.