Duplex Stud bolts Manufacturer & Supplier
Duplex stud bolts are industrial fasteners that are heavy and are produced using duplex stainless steel alloys that are high in mechanical strength and have high corrosion resistance. These types of fasteners have a distinct microstructure of austenite and ferrite dual-phase that enables duplex stud bolts to provide almost 2x the yield strength as compared to standard austenitic stainless steel fasteners. Due to this improved structure, duplex stainless steel stud bolts work remarkably well in hostile settings that are subjected to chlorides, high pressure, and changing temperatures.
Unifit Fastener produces and markets Duplex 2205 Stud Bolts (UNS S31803 / S32205) and Super Duplex Stud Bolts (UNS S32750 / S32760) to meet the requirements of the international standards. They are high-strength duplex stud bolts that have very high pitting and crevice corrosion and stress corrosion cracking resistance and are therefore suitable in offshore and chemical applications. They have excellent tensile strength, fatigue resistance, and dimensional stability that have provided reliable performance in critical bolting assemblies on a long-term basis.
The oil and gas sectors, offshore platforms, marine and shipbuilding, chemical and petrochemical plants, power generation units, desalination plants, and systems of pressure vessels are some of the areas where duplex stud bolts are largely used. They are usually mounted in flanged joints, heat exchangers, piping systems and high-pressure valves. Duplex stud bolts available in a variety of sizes, thread forms and surface coatings are favoured in a variety of applications in the toughest industrial environments.
Request QuoteTable of Contents
- What Are Duplex Stud Bolts?
- Duplex Stud Bolts Material Grades
- Specification of Duplex Stud Bolts
- Send Your Enquiry
- Types of Duplex Stud Bolts Types
- Chemical Composition of Duplex Stud Bolts
- Mechanical Properties of Duplex Stud Bolts
- Duplex Stud Bolts Dimensional & Supply Range
- Duplex Stud Bolts Applications & Uses
- People Ask About Nuts Manufacturer
What Are Duplex Stud Bolts?
Duplex stud bolts are high-steel fasteners that are corrosion-resistant and duplex stainless steel with a balanced ferritic and austenitic construction. This two-stage alloy offers much greater strength than typical stainless steel and has a great deal of resistance to chloride stress corrosion cracking. Duplex stud bolts are commonly used in oil and gas, chemical processing and marine applications and can effectively work in a demanding and harsh environment. Popular grades are Duplex 2205 (UNS S31803 / S32205) and Super Duplex grades (UNS S32750 and S32760) containing chromium, molybdenum and nitrogen to increase resistance to pitting and crevice corrosion.
Duplex Stud Bolts Material Grades
|
Grade Type |
UNS Number |
Common Name |
|---|---|---|
|
Duplex Stainless Steel |
Duplex 2205 |
|
|
Duplex Stainless Steel |
Duplex 2205 |
Specification of Duplex Stud Bolts
|
Parameter |
Specification Details |
|---|---|
|
Product |
Duplex Stud Bolts |
|
Material Specification |
ASTM A193 / ASME SA193 |
|
Manufacturing Standards |
ASTM, ASME, DIN, BS, ISO, JIS (All International Standards) |
|
Size Range (NPS) |
1/2″ to 24″ |
|
Diameter Range |
1/2″ to 1-1/4″ |
|
Length |
3 mm to 200 mm / Custom lengths available |
|
Forms Available |
Hex, Threaded, Square, Round (as per gauge or drawing) |
|
Thread Types |
Metric, UNC, UNF, BSW, BSF, UNEF |
|
Unified Thread Configuration |
ASME B1.1 – 2A/3A, 2B/3B |
|
Metric Thread Standard |
ASME B1.13M – 6h / 6G |
|
UTS / Pipe Threads |
NPT, NPTF, UNS, UNF, UNC, UNEF |
|
Threading Method |
Rolled or Cut; Horizontal or Vertical Tapping |
|
DIN Standards |
DIN 931, 933, 912, 934, 6923, 603, 7981, 7982, 7985, 913, 916, 970 |
|
ISO / JIS Standards |
ISO 4017, ISO 4032, ISO 4033, ISO 7380, JIS Standards |
|
Surface Coating Options |
Cadmium, Hot Dip Galvanized (HDG), PTFE, Phosphate, Teflon, Xylan, Zinc |
|
Test Certification |
EN 10204 / 3.1 Manufacturer Test Certificate |
|
PED Certification |
PED 97/23/EC Certified |
|
AD 2000 Certification |
Merkblatt AD 2000 W2 |
|
Quality Assurance |
Full Material Traceability & Inspection |
Send Your Enquiry
Types of Duplex Stud Bolts Types
Threaded Rod
Tap End Stud Bolt
Stud Bolt
Double Ended Threaded Studs
Chemical Composition of Duplex Stud Bolts
|
Element |
Duplex 2205 (%) |
Super Duplex 2507 (%) |
|---|---|---|
|
Chromium (Cr) |
21 – 23 |
24 – 26 |
|
Nickel (Ni) |
4.5 – 6.5 |
6 – 8 |
|
Molybdenum (Mo) |
2.5 – 3.5 |
3 – 5 |
|
Nitrogen (N) |
0.08 – 0.20 |
0.24 – 0.32 |
Mechanical Properties of Duplex Stud Bolts
|
Property |
Duplex 2205 |
Super Duplex 2507 |
|---|---|---|
|
Tensile Strength |
≥ 620 MPa |
≥ 800 MPa |
|
Yield Strength |
≥ 450 MPa |
≥ 550 MPa |
|
Elongation |
≥ 25% |
≥ 15% |
|
Hardness |
≤ 290 HB |
≤ 310 HB |
Duplex Stud Bolts Dimensional & Supply Range
|
Parameter |
Specification |
|---|---|
|
Size Range |
M6 to M100 / 1⁄4″ to 4″ |
|
Thread Types |
UNC, UNF, Metric, BSW |
|
Length |
Custom as per drawing |
|
Finish |
Plain, PTFE Coated, Hot Dip Galvanized |
|
Standards |
ASTM, ASME, IS, BS |
Duplex Stud Bolts Price
The Duplex Stud Bolts price depends on several factors, including material grade (Duplex 2205 or Super Duplex 2507), bolt diameter, length, thread type, surface coating, quantity ordered, and current raw material market conditions. As a trusted Duplex Stud Bolts manufacturer and supplier, Unifit Fastener offers competitive pricing without compromising on product quality, strength, or international certification standards.
We provide customized quotations based on your exact technical requirements, ensuring cost-effective solutions for high-performance bolting applications.
Contact Unifit Fastener today to receive a detailed price list and bulk order discounts for Duplex Stud Bolts.
Duplex Stud Bolts Applications & Uses
- Oil & Gas Refineries
- Offshore Platforms and Rigs
- Chemical & Petrochemical Plants
- Marine and Shipbuilding Industry
- Power Generation Plants
- Desalination and Water Treatment Plants
- Pressure Vessels and Heat Exchangers
- High-Pressure Flanged Connections
People Ask About Nuts Manufacturer
Q1: What are Duplex Stud Bolts?
Duplex Stud Bolts are fasteners made from duplex stainless steel that offer high strength and excellent corrosion resistance, especially in harsh and chloride-rich environments.
Q2: What is the difference between Duplex and Super Duplex Stud Bolts?
Duplex stud bolts (2205) provide high strength and corrosion resistance, while Super Duplex stud bolts (2507) offer even higher tensile strength and superior resistance to extreme corrosive conditions.
Q3: Where are Duplex Stud Bolts commonly used?
Duplex Stud Bolts are widely used in oil & gas, offshore platforms, chemical plants, marine industries, power generation, desalination plants, and pressure vessel applications.
Q4: What standards do Duplex Stud Bolts follow?
Duplex Stud Bolts are manufactured according to ASTM, ASME, IS, and BS standards.