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Eby fasteners

Stainless steel / duplex & super duplex

Home - Stainless Steel / Duplex & Super Duplex

SS / Duplex & Super Duplex

EBY Fasteners understands the challenges posed by corrosive environments. Our superior range of stainless steel, duplex, and super duplex fittings delivers unmatched protection against saltwater, acids, chemicals, and high-temperature oxidation. These specialized alloys offer superior strength and toughness compared to standard steels, ensuring reliability in high-pressure applications and extreme temperatures

EBY's alloys excel in industries such as offshore and marine, where constant saltwater exposure is a concern. They are also indispensable in chemical and petrochemical plants, maintaining integrity in the presence of acids, solvents, and other harsh chemicals. Additionally, their suitability for high-pressure and high-temperature applications makes them ideal for desalination, water treatment, and critical industrial settings

EBY Fasteners adheres to strict industry standards (ASTM, ASME), guaranteeing consistent quality and performance in your specialty steel fittings. When your project demands resilience in the face of corrosion, trust EBY Fasteners for reliable solutions

Types of SS / Duplex & Super Duplex

  • Elbows : Facilitate changes in flow direction with 90-degree, 45-degree, and reducing elbow options. These alloys provide superior corrosion resistance even in tight bends where stresses can occur.
  • Tees : Create branches or combine flows. Stainless steel tees maintain integrity in corrosive fluids, while duplex and super duplex grades handle extreme pressures and chemical exposure.
  • Reducers : Seamlessly transition between pipe sizes while withstanding the corrosive properties of fluids and high-pressure environments.
  • Couplings, Unions, Nipples : Join pipe sections securely. These corrosion-resistant alloys ensure leak-proof connections and easy maintenance (unions) in harsh settings.
  • Caps and Plugs : Offer permanent or temporary termination of pipes, withstanding corrosion and pressure from the contained fluids.
  • Outlets : Create reliable branch connections resistant to the erosive and corrosive effects often seen in branch line applications
  • Material Specifications : ASTM/ASME Grade is a crucial specification for stainless steel, duplex, and super duplex fittings. Common stainless steel grades include 304/304L and 316/316L. Duplex stainless steel grades are designated as 2205, 2507 (super duplex), and others. Additionally, the Pitting Resistance Equivalent Number (PREN) offers a measure of resistance to localized corrosion, which is especially important in chloride-rich environments.
  • Dimensional Specifications : Dimensional specifications define the physical shape and size of the fittings. This includes the type of fitting (elbow, tee, reducer, etc.), the Nominal Pipe Size (NPS) for standardized pipe diameter reference, and the schedule (e.g., Sch 40, Sch 80) for wall thickness. Also important are the end connections, specifying how the fitting attaches to other components (threaded, flanged, socket weld, butt weld).
  • Performance Specifications : Performance specifications outline the operational capabilities of the fittings. The pressure rating indicates the maximum working pressure the fitting can handle safely. The temperature range defines the acceptable limits for the fitting to function without failure. Mechanical strength, including yield strength, tensile strength, and impact toughness, indicates the fitting's resistance to deformation and fracture under varying loads.
  • Special Considerations : For highly corrosive environments (acids, high chlorides), additional specifications regarding specific material composition and specialized performance testing may be critical for ensuring the longevity and reliability of the fittings
  • Chromium (Cr) : The defining element for all stainless steels. Chromium reacts with oxygen to form a protective oxide layer, providing the inherent corrosion resistance. Stainless steel requires a minimum of 10.5% chromium, with higher percentages (18-30%) found in super duplex grades for extreme environments.
  • Nickel (Ni) : Nickel enhances corrosion resistance, particularly against acids, and improves formability and toughness. It also stabilizes the austenitic crystal structure, which is important in both standard stainless steels and the austenite portion of duplex microstructures.
  • Molybdenum (Mo) : A powerful element for increasing resistance to pitting and crevice corrosion, particularly in environments with chlorides. Molybdenum is more prevalent in super duplex grades, contributing to their exceptional performance in seawater and other aggressive settings.
  • Nitrogen (N) : Nitrogen improves strength, aids in pitting resistance, and stabilizes the austenite phase in duplex and super duplex steels.
  • Duplex & Super Duplex Microstructure : These steels possess a dual-phase structure consisting of austenite and ferrite. Achieving the ideal balance between these phases is crucial for optimizing strength, toughness, and corrosion resistance. Super duplex grades typically aim for a close to 50/50 ratio
  • Exceptional Corrosion Resistance : Chromium forms a passive oxide film that protects the surface. Higher chromium, plus additions of nickel and molybdenum, provide resistance against acids, chlorides, oxidizing environments, and high-temperature corrosion.
  • Superior Strength & Toughness : Exceed the strength of standard carbon steels, with duplex and super duplex offering even greater strength due to their two-phase structure. These alloys also maintain excellent toughness, preventing sudden failures under stress.
  • Balanced Properties (Duplex/Super Duplex) : The combination of austenite and ferrite phases provides a blend of strength, toughness, and corrosion resistance. Super duplex grades offer a near-perfect balance, ideal for extreme environments.
  • Resistance to Chloride Stress Corrosion Cracking : The specific chemistry and microstructure of these alloys make them highly resistant to stress corrosion cracking caused by seawater and other chloride-rich environments.
  • Long Service Life : Their corrosion resistance, strength, and toughness translate into a longer lifespan for components, reducing maintenance and replacement costs in harsh conditions.
  • Suitable for High-Pressure & High-Temperature : Particularly duplex and super duplex grades can excel in demanding applications where pressure, temperature, and corrosive elements create a challenging environment.
  • Weldability : With care in fabrication, and proper selection of filler materials, these alloys can be welded successfully, maintaining their strength and corrosion resistance at joints
  • Refinery & Petrochemical : Stainless steel, duplex, and super duplex are essential in refineries and petrochemical plants. Process equipment like tanks, reactors, distillation columns, and heat exchangers benefit from the corrosion resistance these alloys provide when handling crude oil, refined products, and harsh chemicals.
  • Chemical : The chemical industry relies heavily on high-alloy stainless steel, duplex, and super duplex for their exceptional resistance to acids, caustics, and other aggressive chemicals. These alloys are used in storage containers, reaction vessels, and piping systems, ensuring safe and reliable operation.
  • Oil & Gas : In offshore oil and gas production, duplex and super duplex alloys are indispensable due to their superior resistance to chloride-induced corrosion and high strength. They are used in subsea infrastructure like pipelines, risers, and flowlines, as well as topside process equipment.
  • Power Plant : Coastal power plants or those utilizing brackish water often employ stainless steel, duplex, and super duplex in heat exchangers and condensers to resist corrosion and fouling. Additionally, high-alloy and super duplex grades are used in flue gas desulfurization (FGD) systems to handle highly corrosive environments within scrubbers and other components.
  • Offshore Platforms : Duplex stainless steels offer strength and corrosion resistance for structural elements in offshore platforms, particularly those in splash zones. Systems handling seawater, such as piping, pumps, and valves, often use super duplex grades for their exceptional resistance to seawater corrosion.
  • Shipbuilding : Duplex and super duplex improve the lifespan and reduce maintenance requirements for ballast water tanks constantly exposed to corrosive seawater. The high strength and wear resistance of these alloys also make them ideal for propeller shafts and rudders.
  • Industrial Machineries, Pharmaceuticals, Pumps & Compressors, Dairy & Food, Sugar Mills, Textile Machineries, Fertilizers & Pesticides : Across these diverse industries, stainless steel plays a crucial role in maintaining hygiene, preventing contamination, and resisting corrosion. Applications include process vessels, tanks, piping, pumps, valves, heat exchangers, and more, ensuring the integrity and longevity of equipment exposed to process fluids, cleaning solutions, and agricultural chemicals