ASTM A182 F44 flange UNS S31254 254SMO Flanges

ASTM A182 F44 flange UNS S31254 254SMO Flanges

ASTM A182 F44 flange Manufacturer

ASTM A182 F44 is a super austenitic stainless steel, also known as UNS S31254 or 254 SMO. This grade contains high levels of molybdenum (6%), nickel, and chromium, offering outstanding resistance to pitting, crevice corrosion, and chloride-induced stress corrosion cracking.

With its high content of chromium (19.5-20.5%), nickel (17.5-18.5%), molybdenum (6.0-7.0%), and nitrogen (0.18-0.25%), this grade achieves a Pitting Resistance Equivalent (PREn) value of 42-44, ensuring exceptional resistance to pitting corrosion and crevice corrosion.

Equivalent grade of A182 F44/UNS S31254

A fully austenitic alloy with excellent corrosion resistance in a wide variety of aggressive, aqueous environments

UNSENASTMOther
S312541.4547 (X1CrNiMoN20-18-7)F44254 SMO

ASTM A182 F44 flanges are forged components manufactured from high-alloy austenitic stainless steel known as UNS S31254 (6Mo stainless steel)

A182 F44 Chemical Composition (UNS S31254)

C
CrCuFeMoMnNNiPSSi
Min19.50.5Balance6.00.1817.5
Max0.0220.51.06.51.00.2218.50.0300.0100.8
UNS S31254 A182 F44 Mechanical Properties
Mechanical (room temperature)UTS0.2% Proof StrengthElongationReduction in AreaHardness
MinMinMinMax
650-850 Mpa300 Mpa35.00%50.00%260 HB
Physical Properties
PropertyValue
Density8.0 kg/dm³
Modulus of Elasticity at 20°C195 GPa
Mean Coefficient of Thermal Expansion (20-100°C)16.5 × 10⁻⁶ K⁻¹
Thermal Conductivity at 20°C14 W·m⁻¹·K⁻¹
Specific Thermal Capacity at 20°C500 J·kg⁻¹·K⁻¹
Electrical Resistivity at 20°C0.85 Ω·mm²·m⁻¹
ASTM A182 F44 Flanges Specification

Material: ASTM A182 F44 / UNS S31254 (6Mo)

Type: Weld Neck, Slip-On, Blind, Socket Weld, Threaded, Lap Joint, Orifice

Sizes: 1/2” to 60 ” or custom as per client specifications

Pressure Ratings: Class 150 to 2500, PN6 to PN400

Standards: ASME B16.5, B16.47, EN 1092-1, GOST, DIN

Why S31254 Flages?
Superior Corrosion Resistance

F44 flanges offer excellent resistance to seawater, acidic media, and high chloride applications. They outperform standard stainless steels like 316L in environments where localized corrosion is a concern.

Applications of F44 materials

  • Offshore platforms and subsea systems
  • Desalination plants
  • Chemical processing
  • Pulp and paper industry
  • Marine engineering