Duplex Flanges Manufacturer in India

In the demanding world of industrial engineering, the reliability and performance of every piping component are crucial to the success of your project. As a leading Duplex Flanges Manufacturer in India, CEBEX STEEL INDIA has earned the trust of EPC contractors, procurement managers, and industrial buyers across India, Africa, and global markets. We specialize in the design, manufacture, and export of high-quality duplex and super duplex flanges that meet the most stringent international standards, ensuring leak-proof connections and long-term durability in even the harshest environments.

Our manufacturing facility is equipped with advanced forging and machining technology, enabling us to produce duplex flanges with exceptional dimensional accuracy and surface finish. Whether you are building a refinery, upgrading a power plant, or managing a shipbuilding project, our flanges are engineered to deliver consistent performance and reliability. We understand the critical role that duplex flanges play in maintaining the integrity of piping systems, and we are committed to providing products that exceed your expectations for quality, compliance, and service.

Image: Duplex Flanges Manufacturing

Why Choose Us as Your Duplex Flange Supplier?

Selecting the right supplier for duplex flanges is a strategic decision that impacts the safety, efficiency, and cost-effectiveness of your operations. CEBEX STEEL INDIA stands out as a preferred partner due to our unwavering commitment to quality, technical expertise, and customer satisfaction. We are ISO 9001:2015 and PED certified, reflecting our adherence to global quality management systems and our ability to meet the requirements of international projects.

Our in-house laboratory is equipped to perform a comprehensive range of mechanical, chemical, and non-destructive tests, ensuring that every batch of flanges meets or exceeds client specifications. We maintain full traceability from raw material to finished product, and all shipments are accompanied by detailed mill test certificates (EN 10204 3.1/3.2), NDT reports, and compliance documentation. Our export team is experienced in handling complex logistics, documentation, and packing requirements, making us a reliable partner for buyers in Africa, the Middle East, Southeast Asia, and beyond.

Image: Quality Testing Duplex

Product Overview & Key Features

Our duplex and super duplex flanges are manufactured using premium raw materials sourced from approved mills, and every stage of production is closely monitored for quality assurance. We offer a comprehensive range of flange types, sizes, and pressure ratings, suitable for a wide variety of industrial applications. Whether your requirement is for standard ASME flanges or custom-designed solutions, our engineering team is equipped to deliver with precision and speed.

The following table summarizes the key features and specifications of our duplex flanges:

Feature	Specification/Detail
Standards	ASTM, ASME, EN, DIN, BS, JIS, GOST, ISO
Grades	ASTM A182 F51, F53, F55, F44 (Duplex & Super Duplex)
Pressure Ratings	Class 150, 300, 600, 900, 1500, 2500; PN6?PN400
Size Range	?? NB to 48? NB (DN15?DN1200)
Surface Finish	Machined, coated, or as per client specification
Documentation	Mill Test Certificate (EN 10204 3.1/3.2), NDT, PMI, Hydro, etc.

Types of Duplex Flanges We Manufacture

Our product portfolio covers the full spectrum of duplex and super duplex flanges, each designed for specific applications and operating conditions. Weld neck flanges are preferred for high-pressure systems due to their robust design and ability to withstand extreme temperature fluctuations. Slip-on flanges offer ease of installation and are widely used in lower-pressure applications. Blind flanges are essential for sealing off piping systems or pressure vessel openings, while socket weld and threaded flanges provide reliable connections for smaller diameter pipes.

We also manufacture lap joint, orifice, spectacle blind, long weld neck, and reducing flanges, as well as custom flanges based on client drawings and specifications. Our engineering team works closely with clients to ensure that every flange meets the precise requirements of their project, from material selection to dimensional tolerances.

Image: Various Duplex Flange Types

Grades, Materials & International Standards

Material selection is a critical factor in flange performance, especially in corrosive or high-temperature environments. We offer duplex and super duplex flanges in a wide range of grades, each compliant with relevant international standards. The table below provides an overview of our most commonly supplied grades:

Duplex Grade	Typical Applications	Standards
F51 (2205)	Oil & gas, chemical, marine, desalination	ASTM A182, ASME SA182
F53 (2507)	Offshore, petrochemical, high chloride environments	ASTM A182, ASME SA182
F55	Aggressive chemical, acid, and chloride environments	ASTM A182, ASME SA182
F44	Pulp & paper, chemical, food processing	ASTM A182, ASME SA182

All materials are sourced from reputed mills and are fully traceable, with heat numbers and batch records maintained for every order.

Chemical Composition & Mechanical Properties

Every duplex flange is supplied with comprehensive test certificates, including chemical composition and mechanical property reports. This ensures full compliance with project specifications and international codes. Our in-house laboratory conducts spectrographic analysis, tensile testing, hardness testing, and non-destructive examinations such as ultrasonic and radiographic testing.

Property	Typical Values (Varies by Grade)
Tensile Strength	620?800 MPa (Duplex/Super Duplex)
Yield Strength	450?550 MPa
Elongation	25?35%
Hardness	250?290 HB
Chemical Elements	C, Si, Mn, P, S, Cr, Ni, Mo, N, Cu, etc.

Image: Lab Testing Data

Dimensions, Sizes & Weight Chart

We manufacture duplex flanges in a wide range of dimensions, from ?? NB to 48? NB, with pressure ratings from Class 150 to Class 2500 and PN6 to PN400. Our production is fully compliant with ASME B16.5, B16.47, EN 1092-1, DIN, and other international standards. The following table illustrates typical dimensions for weld neck flanges as per ASME B16.5:

Size (NB)	OD (mm)	Thickness (mm)	Bolt Circle (mm)	No. of Bolts
??	89	11.2	60.3	4
1?	114	13.5	79.4	4
2?	152	17.5	120.7	8
4?	229	24.3	190.5	8
8?	343	30.2	298.5	8

Custom dimensions and special machining are available upon request.

Applications & Industries Served

Our duplex and super duplex flanges are trusted by leading companies and EPC contractors in a diverse range of industries. In the oil and gas sector, our products are used in upstream, midstream, and downstream applications, including pipeline construction, refinery upgrades, and offshore platforms. Power generation clients rely on our flanges for thermal, nuclear, and renewable energy projects, where safety and reliability are paramount. Shipbuilding and marine engineering firms specify our flanges for their corrosion resistance and mechanical strength, while chemical and petrochemical plants value our ability to supply exotic alloy flanges for aggressive process environments.

We also serve the cement, construction, water treatment, mining, and food processing industries, providing tailored solutions for each sector?s unique requirements. Our experience with international projects ensures that we understand the documentation, certification, and logistical needs of global buyers.

Image: Offshore Application

Testing & Quality Assurance

Quality assurance is at the core of our manufacturing philosophy. Every duplex flange undergoes a rigorous inspection process, including dimensional checks, visual inspection, and a full suite of mechanical and non-destructive tests. Our laboratory is equipped with PMI analyzers, ultrasonic flaw detectors, hardness testers, and hydrostatic test rigs. We maintain full traceability for every product, from raw material to finished flange, and provide all necessary certificates, including EN 10204 3.1/3.2, as standard.

Packing, Delivery & Export Capabilities

We understand that safe and timely delivery is critical for project success. Our duplex flanges are packed in export-grade wooden cases or pallets, with each item clearly marked as per client and international requirements. Our logistics team manages all aspects of export documentation, including commercial invoices, packing lists, certificates of origin, and test certificates. We have established shipping partnerships that enable us to deliver to major ports in Africa, the Middle East, Southeast Asia, and Europe, ensuring that your order arrives on time and in perfect condition.

Exporting Duplex Flanges to Africa

As a leading Duplex Flanges Manufacturer in India, we have built a strong reputation for supplying high-quality flanges to major projects across Africa. Our export team understands the unique requirements of African industries and ensures smooth, timely deliveries with complete documentation and compliance. From oil and gas to power and infrastructure, our flanges are trusted by clients in Nigeria, Egypt, Kenya, South Africa, Ethiopia and beyond. To learn more about our specialized solutions for the continent, visit our Africa Duplex Flanges Exporter page.

Related Alloy Flanges ? Stainless Steel, Hastelloy, Inconel, Monel

In addition to duplex flanges, we are also recognized as a leading Stainless Steel Flanges Manufacturer in India, Hastelloy Flanges Manufacturer in India, Inconel Flanges Manufacturer in India, and Monel Flanges Manufacturer in India. These specialty alloy flanges are engineered for extreme environments where superior corrosion resistance, high strength, or temperature stability is required. If your project demands advanced materials, our technical team can guide you in selecting the right alloy flange solution for your application.

Why Choose CEBEX STEEL INDIA?

Our clients choose CEBEX STEEL INDIA for our technical expertise, commitment to quality, and responsive service. We offer direct-from-manufacturer pricing, flexible order quantities, and comprehensive after-sales support. Our engineering team is available to assist with material selection, specification review, and custom design, ensuring that you receive the optimal solution for your application.

Frequently Asked Questions (FAQ)

What standards do your duplex flanges comply with?

All our flanges are manufactured in accordance with ASTM, ASME, EN, DIN, BS, JIS, and GOST standards, with full certification provided.

Can you supply flanges with material test certificates?

Yes, every shipment includes EN 10204 3.1/3.2 mill test certificates and additional test reports as required.

What is your typical delivery time for export orders?

Standard sizes are available ex-stock, while custom orders are delivered within 2?4 weeks, depending on quantity and complexity.

Do you offer custom flange manufacturing?

Absolutely. We can manufacture to your drawings and specifications, including special alloys and non-standard sizes.

How do you ensure quality and traceability?

Every flange is fully traceable, tested, and inspected at every stage, with complete documentation provided.