The ability of grade Super Duplex Stud Bolts to service demanding applications with its exceptional tensile strength and corrosion resistance, make it one of the most revered alloys, especially amongst stainless steel grades. The higher mechanical strength and properties like toughness and hardness are inherited due to its dual microstructure. Moreover, the corrosion resistance of the Alloy 2507 Screws to a wide range of chemicals such as brine, inorganic acids as well as organic acids, and carbide-related intergranular corrosion.

Super Duplex 2507 Fasteners

Super Duplex 2507 Fasteners

Additionally, the Super Duplex 2507 Fasteners offer excellent resistance to chloride stress corrosion cracking, thus making them useful in applications involving the offshore oil and gas industry. A typical oil production platform tends to be self-sufficient in terms of energy and water needs, as these platforms house water desalinators, electrical generation, in addition to all the other equipment deemed necessary in the processing oil and gas.


In fact, the arrangement of a typical platform is such that oil and gas can be either delivered directly onshore by pipeline or to a floating platform or to a tanker loading facility, or both. The construction of these platforms will require alloy grades that have excellent corrosion resistance properties, which is why 2507 Stainless steel bolts are often categorised as an alloy that is durable and can deliver longevity in terms of its service. Usually, the temperature in these oil production platforms is often very elevated. Since Super duplex hex bolt can withstand high temperatures the fasteners are used in the building of their equipment. Furthermore, the Super duplex nuts exhibit good resistance to pitting along with crevice corrosion.

Equivalent of Alloy 2507 Screws

Alloy  European UNS ASTM / ASME
Alloy 2507 1.4410 UNS S32750 A479 / SA479

Super duplex nuts Chemical Resistance Guide

Chemicals Contents (in %)
Sulfur, S 0.020 max
Chromium, Cr 24 – 26
Silicon, Si 0.80 max
Nickel, Ni 6 – 8
Copper, Cu 0.50 max
Molybdenum, Mo 3 – 5
Iron, Fe Balance
Nitrogen, N 0.24 – 0.32
Manganese, Mn 1.20 max
Carbon, C 0.030 max
Phosphorous, P 0.035 max

Super Duplex Stud Bolts Mechanical Analysis

Grade Tensile Strength
(MPa) min
Yield Strength
0.2% Proof (MPa) min
Elongation
(% in 50mm)
Hardness
Rockwell C (HR C)
UNS-S 32750 795 550 15 32max

Physical Behaviour of UNS S32750 Threaded Rod

Properties Metric Imperial
Density 7.8 g/cm3 0.281 lb/in3
Melting point 1350°C 2460°F

Spec Chart of Super Duplex 2507 Fasteners

Standard ASTM A479/ ASME SA479
Sizing 3/6 inch upto 2 inch | M3 – M56
In Form of: Round, Threading, Hex, Square as per Gauge Etc.
Lengths M02 to M152.4