An engineered stainless steel known for its high yield strength & decent corrosion resistance
- High Strength - About 2x stronger yield than 316 stainless steel
- Super Duplex - Decent general corrosion & cracking resistance
- Duplex Grades and chemistry: Duplex 2205, Super Duplex 2507, Zeron 100
- In-depth insight on Duplex 2205 and Super Duplex 2507
- Duplex shoulder bolt features and benefits
- Datasheets for Super Duplex 2507 and Duplex 2205
Duplex 2205 and Super Duplex 2507 stainless steel shoulder bolts are characterized by their high yield strength, which is twice that of the annealed yield strength of typical austenitic stainless steels, like 304 and 316 stainless steel bolts. Because of this, Duplex 2205 and Super Duplex 2507 steel are some of the most common grades of duplex used for bolts with Super Duplex 2507 shoulder bolts being the more corrosion resistant grade of the two.
Super Duplex 2507 shoulder bolts improved corrosion resistance lends itself well too applications prone to stress-corrosion cracking, crevice corrosion, pitting, erosion and general corrosion. Because of the properties of Duplex and Super Duplex stainless steel bolts are often used in chemical processing, petrochemicals, power industry and seawater equipment.
Usage of both Duplex and Super Duplex stainless steel should be limited to temperatures below 570° F as extended elevated temperature exposure can embrittle this material.
The most common grades of Duplex bolts are Duplex 2205 and Super Duplex 2507. Gain more insight on these two grades by accessing our Duplex 2205 and Super Duplex 2507 overviews or by contacting our engineering experts.
Resources: Duplex & Super Duplex Torque Specs
Duplex Bolt Types: Hex Head Bolt, Shoulder Bolt
Duplex Shoulder Bolt Features and Benefits
Duplex shoulder bolts, also called stripper bolts are a unique fastener with three main parts: head, shoulder, and thread. The head has the largest diameter and is where the torque is applied, typically with a socket driver. The shoulder is smooth and unthreaded, and has a set diameter and length. The shoulder’s role is to act as a shaft or dowel for rotating parts, axles for rolling parts, guides for sliding elements, and pivot points. The final part of a Duplex shoulder bolt is the threaded shaft. The threaded portion of a shoulder bolt has a major diameter slightly smaller than the shoulder diameter.
Duplex Bolt Grades, Chemistry & Specifications
Duplex Alloy 2205
Duplex 2205, UNS S32205, is a stainless steel material, whose “Duplex” name is derived from the mixed microstructure which contains roughly equal portions of ferrite and austenite. This grade is the most popular variety and this two-phase material is a significant upgrade from 316 stainless steel in terms of both yield strength and corrosion resistance.
Duplex 2205 Specifications: ASME SA 182, ASME SA 240, ASME SA 479, ASME SA 789, ASME SA 789 Section IV Code Case 2603, ASTM A 240, ASTM A 276 Condition A, ASTM A 276 Condition S, ASTM A 479, ASTM A 790, NACE MR0175/ISO 15156, NORSOK MDS D45 Grade F51, UNS S31803, UNS S32205, W. NR./EN 1.4462, Werkstoff 1.4462 Duplex
Super Duplex Alloy 2507
Super Duplex 2507, UNS S32750, is a two-phase stainless steel and is particularly well suited for use in environments such as warm chlorinated seawater and acidic, chloride containing media. It has similiar properties to Duplex 2205 but is more corrosion resistant and performs well in moderately corrosive environments.
Super Duplex 2507 Specifications: EN 10216-5, ASTM A789; A790, ASTM A182 ASTM A182, ASTM A815, ASTM A240, EN 10088-2, ASTM A479, EN 10088-3 EN 10088, ISO 15156-3, NACE MR0175, Werkstoff 1.4410 S.Duplex
Zeron 100 / F55:
Zeron 100, UNS 32760, is commonly know as F55, which is a slight varient of Super Duplex 2507. This alloy is well suited or seawater applications.
Zeron 100/F55 Specifications: ASTM A 182, ASTM A 182 (Grade F55), ASTM A 240, ASTM A 276, ASTM A 473, ASTM A 479, ASTM A 790, ASTM A 815, ASTM A314, NORSOK MDS 055, UNS S32760, W. Nr./EN 1.4501, Werkstoff 1.4501
Mechanical Data
