Description
Product Detail
Duplex and super duplex steel threaded flanges are forged flanges with internal tapered or parallel threads for connection to threaded pipe or fittings, eliminating the need for field welding in low to medium vibration service. These flanges combine high mechanical strength with excellent resistance to chloride pitting, crevice corrosion and stress corrosion cracking, making them suitable for offshore platforms, seawater systems, chemical plants, firewater lines and process piping.
SASA FLANGE supplies duplex super duplex steel threaded flanges in standard and customized dimensions according to ASME, EN, DIN, JIS, GB and project drawings. Each batch can be supplied with chemical analysis, mechanical testing, dimensional inspection, PMI testing, EN 10204 3.1 certificate and full heat number traceability to support critical industrial procurement requirements.
- ✓Product Name: Duplex Super Duplex Steel Threaded Flanges
- ✓Material Grade: ASTM A182 F51, F53, F55, F60; UNS S31803, S32205, S32750, S32760
- ✓Product Type: Forged threaded flanges with female NPT or BSP threading
- ✓Main Feature: High strength with excellent pitting, crevice and chloride SCC resistance
- ✓Applications: Oil and gas, offshore, desalination, chemical processing, power plants and water treatment
Product Parameters
| Product Name | Duplex Super Duplex Steel Threaded Flanges |
| Material Grade | ASTM A182 F51, F53, F55, F60; UNS S31803, S32205, S32750, S32760 |
| Material Type | Duplex stainless steel and super duplex stainless steel |
| Product Form | Forged threaded flange, female threaded bore, raised face or ring type joint |
| Size Range | DN15 – DN600 (1/2 inch – 24 inch) |
| Pressure Class | Class 150 – 2500 / PN10 – PN100 |
| Sealing Face | RF, FF, RTJ |
| Surface Treatment | Pickling, passivation, machined finish, anti-rust oil on machined surfaces |
| Standard | ASME B16.5, ASME B16.47, EN 1092-1, DIN, JIS B2220, GB/T 9119 or customer specification |
| Inspection | Chemical Analysis, Mechanical Test, PMI Test, Dimensional, Hydrostatic |
| Certificate | EN 10204 3.1 Material Certificate available |
| Processing Service | Cutting, CNC Machining, Custom Drilling, Custom Size Processing |
Chemical Composition
The following chemical composition is for reference for typical duplex and super duplex forged flange grades. Final chemical composition depends on the specified ASTM or EN grade, heat number and material test certificate supplied with the order. SASA FLANGE provides MTC-backed chemistry verification and PMI testing for each production batch when required.
| Element | C | Si | Mn | P | S | Cr | Ni | Mo | Other |
|---|---|---|---|---|---|---|---|---|---|
| F51 / UNS S31803 % | 0.03 max | 1.00 max | 2.00 max | 0.03 max | 0.02 max | 21.0 – 23.0 | 4.5 – 6.5 | 2.5 – 3.5 | N 0.08 – 0.20 |
| F55 / UNS S32760 % | 0.03 max | 1.00 max | 1.00 max | 0.03 max | 0.01 max | 24.0 – 26.0 | 6.0 – 8.0 | 3.0 – 4.0 | N 0.20 – 0.30, Cu 0.50 – 1.00, W 0.50 – 1.00 |
Mechanical Properties
Mechanical properties shown below are typical minimum values for commonly supplied duplex and super duplex flange grades. Actual values may vary according to grade, heat treatment condition, forging reduction ratio and section thickness. Material is supplied in accordance with the applicable ASTM forging standard and verified through mechanical testing as required by the purchase specification.
| Grade | Tensile Strength | Yield Strength | Elongation | Hardness | Density |
|---|---|---|---|---|---|
| ASTM A182 F51 / UNS S31803 | 620 MPa min | 450 MPa min | 25% min | 290 HB max | 7.80 g/cm3 |
| ASTM A182 F55 / UNS S32760 | 750 MPa min | 550 MPa min | 25% min | 300 HB max | 7.80 g/cm3 |
Common Size Table
| Size Range | Pressure Class | Sealing Face | Material | Availability |
|---|---|---|---|---|
| DN15 – DN50 | Class 150 – 600 | RF | F51 / F55 | Stock / Production |
| DN65 – DN300 | Class 150 – 1500 | RF / RTJ | F51 / F53 / F55 | Stock / Production |
| DN350 – DN600 | Class 150 – 2500 | RF / RTJ | F51 / F55 / F60 | Production |
| DN700 – DN1500 | Class 150 – 900 | RF | Duplex or super duplex on request | Made to Order |
Different Specifications Comparison
| Type | Description | Typical Use |
|---|---|---|
| ASME Threaded Flange | Forged flange with female NPT thread in accordance with ASME B16.5 dimensions | Process piping, oil and gas skids, utility lines |
| EN Threaded Flange | Threaded flange produced to EN 1092-1 drilling and facing dimensions with threaded bore by project requirement | European industrial plants and water systems |
| RF Threaded Flange | Raised face threaded flange for use with standard gasketed bolted joints | General industrial service and chemical lines |
| RTJ Threaded Flange | Ring type joint threaded flange for higher pressure sealing performance | High-pressure hydrocarbon and offshore service |
Equivalent Standards and International Names
Threaded flange dimensions and drilling can be manufactured to major international standards, while duplex and super duplex material grades are supplied to the applicable forging specification and equivalent regional designation where required. Equivalent names may vary by project documentation, but SASA FLANGE can match dimensions, pressure ratings and material requirements based on client specifications and approved drawings.
| Standard / Region | Standard Code | Typical Grade / Equivalent |
|---|---|---|
| USA | ASME B16.5 | ASTM A182 F51, F53, F55, F60 |
| Europe | EN 1092-1 | 1.4462, 1.4410 |
| Germany | DIN 2527 / 2566 | DIN equivalent drilling with 1.4462 or 1.4410 material |
| Japan | JIS B2220 | SUS329J3L equivalent project grade on request |
| China | GB/T 9119 | 022Cr22Ni5Mo3N, 022Cr25Ni7Mo4N |
Production Process Flow
Manufacturing control is critical for duplex and super duplex threaded flanges because corrosion resistance and mechanical properties depend on correct material selection, forging practice, heat treatment and machining accuracy. SASA FLANGE applies full traceability and inspection control throughout production.
- 1. Raw Material Selection
- 2. Forging / Cutting
- 3. Heat Treatment
- 4. Rough Machining
- 5. Finish Machining
- 6. Drilling
- 7. Surface Treatment
- 8. Inspection
- 9. Marking
- 10. Packing
- 11. Delivery
| Process Step | Description | Quality Control Point |
|---|---|---|
| Raw Material | Select certified forging billets or plates | Material certificate and traceability |
| Forging | Hot forging to achieve required shape | Forging temperature and reduction ratio |
| Heat Treatment | Solution annealing and rapid cooling as applicable | Temperature and holding time control |
| Machining | Sealing face, threads, bolt holes, dimensions | Dimensional accuracy and surface finish |
| Inspection | Final inspection before shipment | Dimension, surface, PMI, hydrostatic |
Product Inspection
1. Chemical Composition Inspection
Chemical composition inspection verifies that chromium, nickel, molybdenum, nitrogen and other alloying elements meet the specified duplex or super duplex grade requirements. Testing is performed against the applicable ASTM or customer specification to confirm corrosion-resistant performance. Results are linked to the heat number and recorded in the material test certificate for full traceability.
2. Mechanical Properties Testing
Mechanical testing confirms that the forged flange material achieves the required tensile strength, yield strength, elongation and hardness values for the specified grade. These tests help ensure safe use under pressure and mechanical loading. For critical orders, test reports are reviewed together with heat treatment records to verify compliance with project and standard requirements.
3. Dimensional Inspection
Dimensional inspection checks outside diameter, thickness, bolt circle, bolt hole diameter, flange facing dimensions and thread accuracy against the required standard. Sealing face finish and concentricity are also verified to support leak-tight assembly. This inspection ensures interchangeability with mating components in ASME, EN, DIN, JIS or GB piping systems.
4. PMI Testing and Hydrostatic Testing
PMI testing is used to confirm the alloy grade of each flange or production lot before shipment, which is especially important for duplex and super duplex materials. Hydrostatic or pressure-related verification can be arranged according to project scope and applicable standards. SASA FLANGE also provides EN 10204 3.1 certificate, heat number traceability and supporting inspection documents.
Product Packaging
- ✓Wooden Case Packaging: Suitable for high-pressure and large-diameter products
- ✓Pallet Packing with Shrink Wrap: Suitable for batch shipments and standard sizes
- ✓Anti-rust Oil Coating + Waterproof Paper: Used for ocean freight protection
- ✓Individual Plastic Bag + Carton: Used for small fittings and threaded products
- ✓Clear Marking: Grade, size, pressure class, heat number and PO number
Applications
Duplex and super duplex steel threaded flanges are used in corrosive and chloride-containing environments where high strength and excellent resistance to pitting, crevice corrosion and stress corrosion cracking are required. They are selected for welded-free installation in maintenance-sensitive systems, compact skids and threaded branch connections across demanding industrial sectors.
| Industry | Typical Applications | Why This Product Is Used |
|---|---|---|
| Oil and Gas | Wellhead utility lines, chemical injection, firewater and process piping | High strength and strong resistance to chlorides and sour service environments |
| Chemical Processing | Corrosive media transfer lines, reactors and dosing systems | Good resistance to aggressive chemicals and reduced risk of stress corrosion cracking |
| Power Generation | Cooling water, auxiliary piping and desulfurization systems | Reliable pressure performance with long service life in wet corrosive conditions |
| Water Treatment | Desalination skids, seawater intake and brine handling systems | Excellent seawater corrosion resistance and durable threaded assembly |
| Marine and Offshore | Seawater piping, ballast systems and offshore utility modules | Suitable for saltwater exposure, compact assemblies and maintenance-intensive locations |
Why Choose SASA FLANGE?
- ✓Professional manufacturer of Threaded Flanges for global industrial projects
- ✓Customized size, pressure class and material grade according to drawings
- ✓Full standard support: ASME, EN, DIN, JIS, GB, GOST and customer specifications
- ✓Material traceability with heat number control and EN 10204 3.1 material certificate
- ✓Chemical analysis, mechanical testing, PMI testing, hydrostatic and dimensional inspection
- ✓Stock availability for standard items, lead time 3-7 days; custom production 15-30 days
- ✓Export-grade packaging for sea, air and land transportation
- ✓15+ years experience supplying 50+ countries worldwide
FAQ
Q: What is a duplex super duplex steel threaded flange?
A: A duplex or super duplex steel threaded flange is a forged flange with an internally threaded bore used to connect threaded pipe without welding. It is designed for systems requiring corrosion resistance and high mechanical strength. These flanges are commonly used in offshore, chemical and water treatment piping where chloride resistance and easier field installation are important.
Q: What materials are available for duplex super duplex steel threaded flanges?
A: SASA FLANGE commonly supplies threaded flanges in ASTM A182 F51, F53, F55 and F60 grades, including UNS S31803, S32205, S32750 and S32760. Equivalent EN and GB material designations can also be provided based on project requirements. Material selection depends on operating pressure, temperature, chloride concentration and corrosion allowance requirements.
Q: What pressure class is supported?
A: Duplex and super duplex threaded flanges are typically supplied in ASME Class 150, 300, 600, 900, 1500 and 2500, depending on size and design standard. PN-rated EN, DIN and GB versions can also be manufactured, usually from PN10 up to PN100. Final pressure rating should always be selected according to the applicable flange standard and service conditions.
Q: Can SASA FLANGE supply custom sizes?
A: Yes, SASA FLANGE can manufacture custom threaded flanges according to client drawings or special project specifications. We support custom drilling, non-standard dimensions, NPT or BSP threads, raised face or RTJ facing, and special duplex or super duplex grades. Customized marking, inspection scope and packaging can also be arranged for export and EPC procurement requirements.
Q: What certificate is provided?
A: SASA FLANGE supplies EN 10204 3.1 material certificate for duplex and super duplex threaded flanges, together with heat number traceability and standard inspection records. Depending on the order, we can also provide chemical analysis, mechanical test reports, PMI results, dimensional inspection documents and pressure or hydrostatic-related verification records to meet industrial project documentation requirements.
Contact Us
If you are looking for duplex super duplex steel threaded flanges or related custom flange products, please contact SASA FLANGE with your required size, pressure class, material grade, standard, surface treatment, quantity and inspection requirements. Our team will provide professional technical solutions and competitive quotation within 24 hours.
- 📧 Email: sales@sasaflange.com
- 📱 WhatsApp: +86 13764965049
- ☎️ Tel: +86 21 52236361
- 🌐 Website: www.sasaflange.com
