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Super duplex S32750 tubes manufactured to provide high strength and greater corrosion resistance

SUPER DUPLEX • UNS S32750 • WNR 1.4410

Our NORSOK-approved Super Duplex alloy 2507 tubes (UNS 32750) are custom-engineered for the most aggressive subsea and downhole oil and gas applications.
Advantages include:
  • NORSOK-approval
  • Made to order in specialist non-standard sizes
  • Superior strength and corrosion resistance
  • Short lead times
  • Small batch sizes
With 80 years engineering expertise, we specialise in manufacturing corrosion resistant Super Duplex tubes for the increasing hostile temperature and operating environments - where maximising operating efficiency demands total product reliability.
Greater Corrosion Resistance Than Standard Duplex Grades
Super Duplex stainless like S32750, is a mixed microstructure of austenite and ferrite (50/50) which has improved strength over ferritic and austenitic steel grades. The main difference is that Super Duplex has a higher molybdenum and chromium content which gives the material greater corrosion resistance than standard duplex grades.
High Strength and Cost Effective Corrosion Resistance
The balanced duel phase microstructure combines high strength with cost effective corrosion resistance particularly in high chloride environments. Super Duplex has the same benefits as its counterpart – it has lower alloying costs when compared with similar ferritic and austenitic grades with equipment corrosion resistance in chloride containing environments due to the material’s increased tensile and yield strength. In many cases this gives the purchaser the welcomed option of purchasing smaller thicknesses without the need to compromise on quality and performance.
Super Duplex Tubes Sizes
Our tubing sizes typical for Super Duplex range from 3.18 mm (0.125 in) to 31.75 mm (1.25 in) outer diameter OD in seamless form. Available Tube Product form
Typical Applications
  • Offshore platforms
  • Fire-fighting systems
  • Injection & ballast water systems
  • Heat exchangers
Industries predominantly using Super Duplex
Typical Manufacturing Specifications
  • ASTM A789
  • ASME SA-789
  • Also individual customer specifications.

Super Duplex Technical Data
Mechanical Properties

Temper Annealed
Tensile Rm 115 ksi (min)
Tensile Rm 800 MPa (min)
R.p. 0.2% Yield 80 ksi (min)
R.p. 0.2% Yield 550 MPa (min)
Elongation (2” or 4D gl) 15 % (min)

Physical Properties (Room Temperature)

Temper Annealed
Specific Heat (0-100°C) 500°K-1
Thermal Conductivity 15 W.m -1.°K-1
Thermal Expansion 11 μm/μm/°C
Modulus Elasticity 200 GPa
Electrical Resistivity 8.12 μohm/cm
Density 7.8 g/cm3

Chemical Composition (% by weight)

Element Min Max
C - 0.03
Cr 24 26
Cu 0.5 1
Mn - 2
Mo 3 5
N 0.24 0.35
Ni 6 8
P - 0.35
S - 0.015
Si - 1
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