Calico Metal Alloys LLP is a premier supplier of Duplex Steel UNS S31803 Flanges in India. As a leading supplier in the industry, we pride ourselves on delivering excellence and reliability to our valued customers. With a focus on precision engineering and adherence to stringent quality standards, we offer a comprehensive range of flanges tailored to meet diverse industrial needs. Count on us for prompt delivery, competitive pricing, and unparalleled expertise, making us your trusted partner for all your Duplex Steel UNS S31803 Flange requirements in India.

What Are Duplex Steel UNS S31803 Flanges?

Duplex Steel UNS S31803 Flanges are components used in piping systems made out of Duplex stainless steel grade UNS S31803. This steel offers both strength and corrosion resistance, making it suitable for applications where chlorides levels may be high, for instance in environments with higher chloride content or harsh environments where durability and resistance to corrosion must be paramount. These flanges connect pipes, valves or equipment and form vital systems where durability and resistance against corrosion must be given top consideration, typically they connect pipes, valves or equipment and connect critical systems where durability must not only last but endures in terms of durability if corrosion-resistance must also take priority when connecting critical systems where durability must also resist.

Duplex Steel UNS S31803 Flanges

Manufacturing Process Of Duplex S31803 Flanges

Raw Material

The system controls inspect the raw material quality at the first stage in accordance with the test certificate as well as dimensions and appearance.

Material Cutting

This method of making flanges involves cutting stripes from the center plate and rolling them into a circle.


Compared to cast flanges, forged flanges typically contain less carbon and are less likely to corrode. Temperature control, weight measurement, and material grade checking are used in forgings.

Heat Treatment

The total forging cooling speed is the slowest throughout this heat treatment procedure; the standardizing and decreasing cooling speeds are faster.

Final Inspection

Measure and check the flange's dimensions and size using this procedure.

Duplex Steel S31803 Flanges Specifications

Standard ASTM A182 / ASME SA182
Dimensions ANSI/ASME B16.5, B16.47 Series A & B, B16.48, BS4504, BS 10, EN-1092, DIN, ANSI Flanges, ASME Flanges, BS Flanges, DIN Flanges, EN Flanges, GOST Flange, ASME/ANSI B16.5/16.36/16.47A/16.47B, MSS S44, ISO70051, JISB2220, BS1560-3.1, API7S-15, API7S-43, API605, EN1092
Flange Size Chart 1/2" (15 NB) to 48" (1200NB), DN10~DN5000
Pressure Rating Class 150 LBS, 300 LBS, 600 LBS, 900 LBS, 1500 LBS, 2500 LBS
Pressure Calculation in DIN 6Bar 10Bar 16Bar 25Bar 40Bar / PN6 PN10 PN16 PN25 PN40, PN64
JIS 16 K, 5K, 10 K, 20 K, 30 K, 40 K, 63 K
Flange Connection / Flange Face Type Raised Face (RF), Ring Type Joint (RTJ), Flat Face (FF), Large Male-Female (LMF), Lap-Joint Face (LJF), Small Male-Female (SMF), Small Tongue, Large Tongue & Groove, Groove, Flange Pipe.
Origin West Europe / Japan / Indian / USA / Korean
Types of Flanges Threaded / Screwed / Forged / Plate
Coating Yellow Transparent, Zinc Plated, Anti-rust Paint, Oil Black Paint, Cold and Hot Dip Galvanized
Production technique Used Heat treated, Forged and Machined
Equipment Press machine, Bending machine, Pushing Machine, Sand-blasting machine, electric bevelling machine etc.
Test Certificates EN 10204/3.1B, Raw Materials Certificate, 100% Radiography Test Report, Third Party Inspection Report, etc

Types Of Duplex Stainless Steel S31803 Flanges


Duplex Steel S31803 Weld Neck Flange


Duplex Steel S31803 Blind Flange


Duplex Steel S31803 Slip on Flange


Duplex Steel S31803 Socket weld Flange


Duplex Steel S31803 Spectacle Blind Flange


Duplex Steel S31803 Threaded Flange


Other Types Of Duplex Steel S31803 Flanges

DSS S31803 Flanges Duplex Steel S31803 Lap Joint Flange
Duplex Steel S31803 Long Weld Neck Flange Duplex Steel S31803 Industrial Flanges
S31803 Duplex Steel Forged Flanges Duplex Steel S31803 RTJ Flange
S31803 Duplex Stainless Steel Plate Flange UNS S31803 Square Flange
F51 Duplex Stainless Steel Flanges Duplex Stainless Steel F51 SORF Flange
DSS S31803 WNRF Flange Duplex Steel S31803 SWRF Flanges
ASME SA182 Duplex Steel S31803 Pipe Flanges ASTM A182 Duplex Steel S31803 Plate Flange
Duplex Stainless Steel S31803 Flat Face Flange Duplex Steel S31803 BS 4504 Flanges
Duplex Steel S31803 Orifice Flange S31803 Duplex Steel Groove & Tongue Flanges
ANSI B16.5 Duplex Steel S31803 Flanges S31803 Duplex Steel Loose Flange

Duplex Steel UNS S31803 Flanges Equivalent Grade

UNS S31803 duplex stainless steel grade is widely recognized for its excellent corrosion resistance and high strength properties, making it suitable for applications where both strength and corrosion resistance are crucial. Equivalent grades to UNS S31803 include ASTM A182 F51, EN 1.4462 and DIN X2CrNiMoN22-5-3 due to similar mechanical properties and chemical composition that makes these grades interchangeable in various industrial settings such as oil & gas industries as well as chemical processing plants or marine engineering due to their exceptional performance under demanding circumstances.

S31803 1.4462 S31803 4462-318-03-I

Chemical Composition of Duplex Steel UNS S31803 Flanges

UNS S31803, commonly used as duplex stainless steel, typically features 22% chromium, 5-6% nickel, 3% molybdenum and 0.1-0.3% nitrogen as its core constituents; additional alloying elements may include manganese silicon or copper to round off this impressive composition, making this duplex steel ideal for various flange applications in various industries.

UNS Designation Type Composition, % B
C Mn P S Si Cr Ni N Mo Other Elements C
S31803 . . . 0.030 2.00 0.030 0.020 1.00 21.0-23.0 4.5-6.5 0.08-0.20 2.5-3.5 . . .

Mechanical Properties of Duplex Steel UNS S31803 Flanges

Due to their dual-phase microstructure, Duplex Steel UNS S31803 flanges exhibit excellent mechanical properties. Their typical mechanical characteristics include tensile strengths between 620 to 800 MPa; yield strengths at approximately 450 MPa and 25% or greater elongation; in addition, these flanges boast excellent corrosion and cracking resistance - ideal properties for various demanding industries like oil & gas, chemical processing and marine engineering.

UNS Designation Type Condition Tensile Strength, min, ksi [MPa] Yield Strength,A min, ksi [MPa] Elongation in 2 in. [50 mm] or 4D, min, % Reduction of Area, min, %B,C Brinell Hardness, max
S31803 . . . annealed 90 [620] 65 [450] 25 . . . 290

Duplex Steel UNS S31803 Flanges Size

Duplex Steel UNS S31803 flanges come in sizes that span 1/2" to 48", (DN15-1200). Popular styles of these flanges are weld neck flanges which exhibit excellent corrosion resistance due to the duplex microstructure; other popular options are slip-on, socket weld blind lap joint threaded. They're widely used across a range of industries such as oil & gas chemical processing marine engineering where strength & corrosion resistance are crucial components - not to mention international standards like ASTM, ASME, ANSI, DIN which ensure quality and compatibility across industries and environments alike.

Applications of Duplex Steel UNS S31803 Flanges

Duplex Steel UNS S31803 Flange Applications Duplex steel UNS S31803 flanges find use across numerous industries thanks to their excellent mechanical properties, corrosion resistance and strength - these flanges find application across numerous sectors including:

Aerospace: Duplex steel flanges can be utilized in aerospace applications where lightweight components requiring high strength and corrosion resistance are critical components, such as aircraft or spacecraft. They offer excellent strength-to-weight ratio and corrosion protection capabilities.

Construction: Duplex steel flanges are commonly utilized in structural applications like bridges, buildings and infrastructure that demand strength and corrosion resistance under extreme environmental conditions.

Marine Industry: Due to their resistance against seawater corrosion and biofouling, duplex steel flanges have found widespread application within marine applications like shipbuilding, offshore platforms and equipment.

Power Generation: Duplex steel flanges have long been used in power generation plants utilizing nuclear, thermal and renewable energies - such as nuclear reactors and turbines for steam/water pipelines as well as turbine systems/heat exchangers/coils etc.

Water Treatment: Flanges constructed of duplex steel can be found in water treatment facilities that require protection from corrosion, erosion and abrasion, such as pipelines, valves or pumps used to transport and treat both drinking water and wastewater. These duplex flanges serve a multitude of uses within these environments such as pipes, valves or pumps that carry and treat it all efficiently.

Oil and Gas Industry: Duplex steel flanges are widely utilized within the oil and gas industry for use with pipe systems on offshore platforms and subsea installations, often at extreme pressure and temperature conditions encountered when extracting, refining or transporting oil and gas resources. They have proven resilient against corrosion while withstanding exposure to harsh environments found during oil extraction, refining or transportation processes.

Chemical Processing: Duplex steel flanges are well suited for chemical processing applications where resistance against acids, alkalis, or any other potentially corrosive chemicals is key - pipelines, reactors and vessels at chemical plants often use duplex steel flanges in chemical plants for this reason.

Duplex steel UNS S31803 flanges offer unparalleled versatility, durability, and corrosion protection for use across many demanding industries.

Electrical Industry


Automotive Industry


Construction Industry


Defence Industry


Pharmaceutical Industry


Petroleum Industry


Petrochemical Industry


Milk & Dairy Industry

Milk & Dairy

Export & Supply Destinations Of Duplex S31803 Flanges

Liechtenstein, Spain, Belarus, Serbia, France, Finland, Bulgaria, Sweden, Latvia, Moldova, Monaco, Azerbaijan, Czechia/Czech Republic, Luxembourg, Belgium, Italy, Austria, Slovakia, Hungary, Greece, Romania, Switzerland, Germany, Turkey, Portugal, Russia, Ireland, Denmark, Lithuania, United Kingdom, Cyprus, Norway, Estonia, Poland, Ukraine, Malta, Croatia, Netherlands.

Sri Lanka, Kuwait, Indonesia, Japan, Taiwan, Israel, Philippines, Myanmar, Macau, Bangladesh, Singapore, Lebanon, Saudi Arabia, Afghanistan, Hong Kong, Iraq, Armenia, Mongolia, Egypt, Qatar, Bhutan, Thailand, Turkey, Bahrain, Maldives, British, North Korea, Nepal, United Arab Emirates, Iran, Kyrgyzstan, South Korea, Malaysia, Azerbaijan, Oman, Vietnam, India, Jordan, China, Russia.

Angola, Liberia, Mauritius, Libya, Mauritania, Eswatini, Mozambique, Namibia, Senegal, Niger, Zambia, Zimbabwe, Tunisia, Central African Republic, Gambia, Kenya, Uganda, Nigeria, Burkina Faso, Morocco, Ethiopia, South Africa, Egypt, Tanzania, Algeria, Madagascar, Rwanda, Botswana, Burundi, Seychelles, Cameroon.

El Salvador, Jamaica, Antigua and Barbuda, Belize, Dominican Republic, Canada, Panama, Costa Rica, Barbados, Bahamas, Haiti, United States of America, Grenada, Honduras, Cuba, Guatemala, Saint Lucia, Saint Vincent and the Grenadines, Nicaragua, Dominica, Trinidad and Tobago, Mexico.

Paraguay, Colombia, Guyana, Suriname, Ecuador, Bolivia, Venezuela, Brazil, Peru, Argentina, Chile, Uruguay.