Duplex Steel Pipe Fittings Manufactured and Exported in Mumbai
We get a version of the same call every few weeks: someone’s 316L piping is pitting out earlier than it should in a chloride line, and they want to know if duplex is worth the switch. Short answer usually, yes, if the environment actually warrants it. Kalpataru Piping Solution manufactures duplex steel pipe fittings in UNS S31803 and S32205 out of our Mumbai unit, to ASTM A815 / ASME SA815, dimensioned to B16.9 and B16.11. What makes the grade worth the extra cost isn’t marketing, it’s the microstructure. Duplex splits roughly evenly between austenite and ferrite, and that combination gets you close to double the yield strength of plain 316L along with a real jump in resistance to chloride pitting and stress cracking.
That’s the whole reason offshore platforms and desalination lines keep specifying it. We test every batch for PMI and ferrite content before it leaves the shop floor, and every shipment carries an EN 10204 3.1 certificate not because a checklist told us to, but because that’s the paperwork a buyer actually needs when something goes wrong two years down the line and someone asks for traceability. If you’ve already decided on a duplex, send over your size list. If you’re still deciding between duplex and 316L, happy to talk through it first.
Table of content
- What Makes Duplex Steel Pipe Fittings Different?
- Duplex Steel Pipe Fittings Grades
- Duplex Steel Pipe Fittings Technical Specifications
- Types of Duplex Steel Pipe Fittings
- Duplex Steel Pipe Fittings Chemical Composition (%)
- Duplex Steel Pipe Fittings Mechanical Properties
- Duplex Steel Pipe Fittings Physical Properties
- Duplex Steel Pipe Fittings Dimension & Weight Chart
- Where These Duplex Steel Pipe Fittings Actually Get Used
- Duplex 2205 vs Stainless Steel 316L: Which One Do You Actually Need?
- How We Manufacture and Test Every Batch
- Duplex Steel Pipe Fittings Price List
- People Ask About Duplex Steel Pipe Fittings Manufacturer
What Makes Duplex Steel Pipe Fittings Different?
Here’s the thing about duplex that a lot of spec sheets skip over: it’s not a stronger version of stainless steel, it’s a different animal entirely. The name comes from its microstructure being split roughly 50/50 between austenite and ferrite, and each phase is doing a different job. Ferrite is what gives it the strength and the stubborn resistance to chloride stress cracking. Austenite is what stops it from being brittle and hard to weld, which is a problem some high-ferrite alloys run into. UNS S31803 (you’ll also see it called Werkstoff 1.4462) and the newer, tighter-spec UNS S32205 are the two grades most people mean when they say ‘duplex 2205’ and they sit in a sweet spot between ordinary 316-family stainless and the pricier super duplex grades, both on what they can handle and what they cost.
We make these fittings alongside our regular Duplex Steel S31803/S32205 pipe fittings line, so if your BOM also needs Duplex Steel S31803/S32205 flanges, Duplex Steel tube fittings, or Duplex Steel valves, it’s genuinely less hassle to get it all from one mill lineage than to chase down certificates from three vendors after the fact we’ve seen how much time that eats up on the buyer’s side.
Duplex Steel Pipe Fittings Grades
Duplex Steel Pipe Fittings Technical Specifications
Parameter | Details |
|---|---|
Governing Specification | ASTM A815 / ASME SA815 |
Grades | UNS S31803, UNS S32205 (also S32750/S32760 super duplex on request) |
Equivalent Designation | Werkstoff 1.4462, Grade F51/F60 |
Size Range | 1/2″ NB to 24″ NB (DN15–DN600) |
Thickness | SCH 5S to SCH XXS |
Construction | Seamless / Welded / Fabricated |
Dimensional Standards | ASME/ANSI B16.9, B16.28, MSS-SP-43, BS4504, BS1560, BS10 |
Bending Radius | R = 1D, 2D, 3D, 5D, 6D, 8D, 10D, or custom on drawing |
End Finish | Beveled for welding, threaded (NPT/BSP), or socket-weld |
Testing Performed | PMI verification, ferrite content testing, hydrostatic test, intergranular corrosion test, radiography |
Types of Duplex Steel Pipe Fittings
Duplex Steel Pipe Fittings Chemical Composition (%)
Element | UNS S31803 | UNS S32205 |
|---|---|---|
Chromium (Cr) | 22.0 – 23.0 | 21.0 – 23.0 |
Nickel (Ni) | 4.50 – 6.50 | 4.50 – 6.50 |
Molybdenum (Mo) | 3.0 – 3.5 | 2.50 – 3.50 |
Nitrogen (N) | 0.14 – 0.20 | 0.08 – 0.20 |
Manganese (Mn) | 2.00 max | 2.00 max |
Silicon (Si) | 1.00 max | 1.00 max |
Carbon (C) | 0.030 max | 0.030 max |
Phosphorus (P) | 0.030 max | 0.030 max |
Sulfur (S) | 0.020 max | 0.020 max |
Iron (Fe) | Balance (63.72 min) | Balance (63.54 min) |
Duplex Steel Pipe Fittings Mechanical Properties
Property | Value |
|---|---|
Tensile Strength (min) | 620 MPa |
Yield / Proof Strength (min, 0.2%) | 450 MPa |
Elongation (min, A50mm) | 25% |
Hardness (max) | 290 HB |
Modulus of Elasticity | 200 GPa |
Density | 7.8 g/cm³ |
Duplex Steel Pipe Fittings Physical Properties
| Property | Duplex 2205 | Comparable 316L |
|---|---|---|
| Density | 7.8 g/cm³ | 8.0 g/cm³ |
| Thermal Conductivity | 19 W/m·K | 16 W/m·K |
| Melting Point | 1350–1450°C | 1371–1399°C |
| Service Temperature Range | -50°C to 300°C | -196°C to 500°C |
Duplex Steel Pipe Fittings Dimension & Weight Chart
Dimension Chart (ASME B16.9, Select Sizes)
NPS (inch) | O.D. (mm) | 90° LR Elbow C-to-F (in) | 45° LR Elbow C-to-F (in) | Equal Tee C-to-E (in) |
|---|---|---|---|---|
1/2 | 21.3 | 1 1/2 | 5/8 | 1 1/2 |
1 | 33.4 | 1 1/2 | 7/8 | 1 1/2 |
2 | 60.3 | 3 | 1 3/8 | 3 |
4 | 114.3 | 6 | 2 1/2 | 4 1/2 |
6 | 168.3 | 9 | 3 3/4 | 6 |
8 | 219.1 | 12 | 5 | 7 |
12 | 323.9 | 18 | 7 1/2 | 10 |
Approximate Weight Chart (per piece, 90° Elbow)
Size (inch) | Weight (kg) |
|---|---|
1/2 | 0.08 |
3/4 | 0.11 |
1 | 0.15 |
1 1/4 | 0.25 |
1 1/2 | 0.39 |
2 | 0.66 |
2 1/2 | 1.37 |
3 | 2.19 |
4 | 4.12 |
5 | 6.89 |
6 | 10.7 |
8 | 21.6 |
10 | 37.0 |
12 | 61.0 |
16 | 121.0 |
24 | 377.0 |
Full dimension and tolerance charts up to 48″ NB are available in our downloadable technical PDF and price list.
Where These Duplex Steel Pipe Fittings Actually Get Used
Most of our duplex orders end up in one of these places — not a random spread, a pretty consistent pattern:
- oil and gas pipelines and offshore platforms
- chemical and petrochemical processing plants
- marine and shipboard piping systems
- high-pressure hydraulic systems
- desalination and seawater intake lines
- pulp and paper mills
- medical equipment
- basically anywhere the fluid running through the pipe has chlorides in it and corrosion has already caused a headache once
Now, duplex 2205 isn’t the ceiling. If you’re going deeper offshore, dealing with sour service, or the chloride load is just higher than 2205 is rated for, our Super Duplex Steel S32750/S32760 pipe fittings are the next step up. On the flip side, we’ve had customers come to us assuming they need duplex when the service is actually mild enough that Stainless Steel 316/316L/316Ti pipe fittings would do the job for less. Worth a quick conversation before you commit either way.
Duplex 2205 vs Stainless Steel 316L: Which One Do You Actually Need?
Almost every enquiry we get eventually circles back to this question, so let’s just answer it plainly instead of dancing around it:
Factor | Duplex 2205 (UNS S31803/S32205) | Stainless Steel 316L (UNS S31603) |
|---|---|---|
Group | Duplex (austenitic-ferritic) | Austenitic |
Tensile Strength | 620 MPa min | 485 MPa min |
Typical Service Life | 25–30 years | 20–25 years |
Service Temperature | -50°C to 300°C | -196°C to 500°C |
Chloride Environments | Excellent — best suited | Not advisable long-term |
Density | 7.8 g/cm³ | 8.0 g/cm³ |
Relative Price (per kg, India) | US $6 – 8 | US $4 – 5 |
Our honest take: if the line is genuinely chloride-heavy — seawater, produced water, brine — duplex pays for its higher price tag several times over just in downtime you don’t have. If it’s a milder service, don’t overspend; 316L is still the more sensible pick.
How We Manufacture and Test Every Batch
- Raw material verification — PMI testing and mill certificates traceable to EN 10204 3.1
- Forming — press machines, hot/cold bending, and hydraulic pushing for seamless bends
- Heat treatment — solution annealing at controlled temperature to maintain the correct austenite-ferrite balance
- Surface finishing — pickling and passivation to restore the protective oxide layer
- Non-destructive testing — ferrite content measurement, ultrasonic flaw detection, radiography, intergranular corrosion testing
- Final inspection — dimensional checks, hydrostatic testing, and third-party inspection through Lloyds, TUV, or Bureau Veritas on request
Certifications & Standards We Work To
- ISO 9001:2015 — Quality Management
- ISO 14001:2015 — Environmental Management
- ISO 45001:2018 — Occupational Health & Safety
- ASTM A815 / ASME SA815 — Manufacturing Standard
- ASME B16.9 & B16.11 — Dimensional Standards
- NACE MR0175 / ISO 15156 — Sour Service Compliance
- EN 10204 3.1 — Mill Test Certification
Duplex Steel Pipe Fittings Price List
Item | Price in India (INR) | Price in USD | Price in UAE (AED) |
|---|---|---|---|
Duplex Steel Elbow (per piece) | ₹922 | $19.33 | AED 46.61 |
Duplex Steel Elbow (budget size) | ₹452 | $5.85 | AED 26.50 |
Duplex Pipe Fittings (average, per piece) | ₹2,460 | $28.21 | AED 107.27 |
Duplex Steel Weld Fittings | ₹1,298 | $20.00 | AED 68.44 |
Duplex Steel 90° Elbow | ₹1,767 | $29.78 | AED 74.30 |
Duplex Reducer (per kg) | ₹492 | $9.85 | AED 29.50 |
Duplex Steel 45° Elbow | ₹5,621 | $65.17 | AED 257.30 |
Duplex Steel Bend | ₹1,304 | $17.82 | AED 56.11 |
These are indicative figures that move with schedule, seamless-versus-welded construction, and order quantity. Send us your actual size list and we’ll come back with firm, size-wise pricing.
People Ask About Duplex Steel Pipe Fittings Manufacturer
Duplex 2205 Pipe Fittings are high-performance duplex stainless steel fittings available in grades UNS S31803 and UNS S32205. They combine excellent strength, corrosion resistance, and durability for industrial applications.
S31803 material is a duplex stainless steel grade known for superior corrosion resistance, high tensile strength, and long-lasting performance in chemical, hydraulic, and high-temperature environments.
UNS S32205 fittings offer exceptional strength, resistance to galling, leak-proof performance, and stability under high temperatures. They are suitable for chemical, marine, and industrial applications.
They are widely used in oil & gas, chemical processing, marine environments, medical devices, and high-temperature hydraulic systems.