Water and wastewater treatment facilities necessitate the utilization of exceptionally resilient and corrosion-resistant materials to ensure the utmost reliability and longevity of their equipment and components.
In this regard, the remarkable properties of Super Duplex 2507 stainless steel make it an exemplary option.
This article aims to explore the multitude of benefits and diverse applications of Super Duplex 2507 stainless steel in the domain of water and wastewater treatment equipment and components.
Keep reading this article to learn more about this high performing alloy.
Table of Contents for Super Duplex 2507 Stainless Steel: A Premier Choice for Water & Wastewater Treatment Equipment
Chemical Composition of Super Duplex 2507 Stainless Steel
Duplex 2507 (UNS S32750) is a super duplex stainless steel with 25% chromium, 4% molybdenum, and 7% nickel designed for demanding applications which require exceptional strength and corrosion resistance, such as chemical process, petrochemical, and seawater equipment, water and wastewater treatment equipment.
Super Duplex 2507 has excellent resistance to chloride stress corrosion cracking, high thermal conductivity, and a low coefficient of thermal expansion.
The high chromium, molybdenum, and nickel levels provide excellent resistance to pitting, crevice, and general corrosion. Compared to Duplex 2205, this alloy has better overall performance.
The chemical composition of stainless steel grade Super Duplex 2507 is outlined in the following table:
Physical Properties of Super Duplex 2507 Stainless Steel
The physical properties of stainless steel grade Super Duplex 2507 are shown below:
Mechanical Properties of Super Duplex 2507 Stainless Steel
Super Duplex 2507 stainless steel mechanical properties make it suitable for demanding environments and critical applications.
Tensile Strength and Yield Strength
Super Duplex 2507 stainless steel exhibits impressive tensile strength and yield strength. Tensile strength refers to the maximum stress the material can withstand before it breaks, while yield strength represents the stress at which permanent deformation begins. Typically, Super Duplex 2507 has a minimum tensile strength of 750 MPa (109 ksi) and a minimum yield strength of 550 MPa (80 ksi).
Impact Toughness
Impact toughness is a crucial property for materials that are subjected to sudden impact or shock loading. Super Duplex 2507 stainless steel possesses excellent impact toughness, allowing it to withstand sudden loads without fracturing or experiencing significant deformation. This characteristic ensures its reliability in applications where impact resistance is vital.
Fatigue Strength
Fatigue strength measures the ability of a material to withstand cyclic loading without failure. Super Duplex 2507 stainless steel demonstrates high fatigue strength, making it suitable for applications subjected to repeated stress cycles, such as offshore structures and components exposed to vibration or alternating loads.
Hardness
Super Duplex 2507 stainless steel exhibits a high hardness level, which contributes to its strength and wear resistance. The hardness of this stainless steel grade typically ranges from 250 to 290 HB (Brinell hardness). The hardness can be further enhanced through heat treatment processes, such as solution annealing and quenching.
Creep Resistance
Creep resistance refers to a material's ability to resist deformation under prolonged exposure to high temperatures. Super Duplex 2507 stainless steel demonstrates excellent creep resistance, allowing it to maintain its mechanical integrity even at elevated temperatures. This property is crucial in applications where the material is subjected to long-term exposure to high temperatures.
Mechanical property requirements for annealed, hot finished product Super Duplex 2507 stainless steel as specified in ASTM A276 and ASME SA276:
2507 Super Duplex Equivalents and International Industry Standards
In the list below we reported the SAF 2507 Super Duplex international industry standards and equivalents:
• ASTM A-479-S32750
• ASTM A-276
• ASTM A-182 (53)
• ASME A276/479
• EN 10204 3.1
• NACE MR0175/ISO 15156
• API 6A PSL3
• Norsok – M-630
• MDS D57
• Super Duplex
• UNS S32750
If you are unsure about the most suitable stainless steel for your application, you can get in touch with our team at any time.
The Unrivalled Qualities of Super Duplex 2507 Stainless Steel
Super Duplex 2507 stainless steel represents a top-tier alloy renowned for its outstanding attributes, specifically engineered to meet the rigorous demands of water and wastewater treatment facilities.
With a composition that includes a significant proportion of chromium, nickel, molybdenum, and other alloying elements, Super Duplex 2507 stainless steel exhibits unparalleled resistance to corrosion, exceptional strength, and commendable weldability.
Superior Corrosion Resistance
Super Duplex 2507 stainless steel boasts remarkable resistance against a wide range of corrosive substances found in water and wastewater treatment environments.
Its inherent ability to withstand corrosion, including chloride-induced stress corrosion cracking (SCC) and pitting corrosion, ensures the integrity and longevity of the equipment and components in these critical applications.
Practical experience with SAF 2507 in organic acids, e.g. in terephthalic acid plants, has shown that this alloy is highly resistant to this type of environment. The alloy is therefore a competitive alternative to high alloyed austenitic and nickel alloys in applications where standard austenitic stainless steels corrode at a high rate.
Resistance to inorganic acids is comparable to, or even better than that of high alloy austenitic stainless steels in certain concentration ranges. SAF 2507 stainless steel can resist sulfuric acid, sulfuric acid contaminated with 2000 ppm chloride ions, and hydrochloric acid, respectively.
High Strength
One of the key advantages of Super Duplex 2507 stainless steel lies in its exceptional strength. With a strength nearly twice that of conventional austenitic stainless steel, it offers enhanced load-bearing capacity and structural integrity, even in demanding operating conditions. This elevated strength allows for the construction of equipment with thinner walls, reducing weight and optimizing efficiency.
Excellent Weldability
Weldability is a crucial aspect in the fabrication and installation of equipment and components. Super Duplex 2507 stainless steel exhibits commendable weldability, enabling efficient and reliable joining processes. This facilitates the construction of complex structures and ensures seamless integration of various components, contributing to the overall performance and longevity of the system.
General Applications of Super Duplex 2507 Stainless Steel
Super Duplex 2507 stainless steel finds extensive applications in water and wastewater treatment facilities. It is employed in the fabrication of pipes, tubes, valves, pumps, fittings, and various other critical components. Its exceptional properties make it suitable for handling corrosive fluids, high-pressure environments, and challenging operating conditions.
Stainless steel Super Duplex 2507 is designed to handle highly corrosive conditions and situations where high strength is required.
High molybdenum, chromium and nitrogen content in Super Duplex 2507 help the material withstand pitting and crevice corrosion. The material is also resistant to chloride stress corrosion cracking, to erosion corrosion, to corrosion fatigue, to general corrosion in acids. This alloy has good weldability and very high mechanical strength.
Typical applications for SAF 2507 Super Duplex:
Oil and gas exploration and production
Chloride-containing environments: such as industrial wastewaters, seawater handling and process systems. Hydraulic and process fluid tubes in umbilical
Seawater cooling: Tubing for heat exchangers in refineries, chemical industries, process industries and other industries using seawater or chlorinated seawater as coolant
Salt evaporation: Evaporator tubing for production of corrosive salts, e.g. chlorides, sulphates and carbonates
Desalination plants: Pressure vessels for reverse osmosis units, tube and pipe for seawater transport, heat exchanger tubing
Geothermal wells: Heat exchangers in geothermal exploitation units, systems exposed to geothermal or high salinity brines, tubing and casing for production
Oil refining and petrochemical and gas processing: Tubes and pipes where the process environment contains a high amount of chlorides, or is contaminated with hydrochloric acid
Pulp and paper production: Material for chloride-containing bleaching environments
Chemical processing: Organic acid plants, also when process solutions are contaminated with e.g. chlorides
Mechanical components requiring high strength: Propeller shafts and other products subjected to high mechanical load in seawater and other chloride-containing environments
Desulfurization units: As reheater tubes in flue gas desulfurization systems. The good mechanical and corrosion properties make SAF 2507 an economical choice in many applications by reducing the life cycle cost of equipment.
Applications of Super Duplex 2507 Stainless Steel in Water and Wastewater Treatment
Super Duplex 2507 stainless steel finds extensive applications in various water and wastewater treatment equipment and components. These include:
Evaporators: vacuum evaporators play an important role in wastewater treatment and super duplex 2507 is commonly used as the boiler material.
Pumps and valves: Super Duplex 2507 is commonly used for pump impellers, shafts, and valves due to its resistance to erosion and corrosion.
Pipes and fittings: Its superior corrosion resistance makes it suitable for pipelines and fittings that transport water, chemicals, and wastewater.
Heat exchangers: Super Duplex 2507 is utilized in heat exchangers due to its excellent heat transfer properties and resistance to corrosion.
Filters and screens: It is employed in filter plates, screens, and filter housings due to its resistance to fouling and corrosion.
Desalination equipment: Super Duplex 2507 stainless steel is ideal for desalination plants where it is exposed to highly saline and corrosive environments.
At YASA ET we ensure our clients that we select the best stainless steel for their application. If you want to learn more about our stainless steel components and equipment kindly get in touch with us.
Conclusion
Super Duplex 2507 stainless steel showcases exceptional mechanical properties that make it a preferred choice for demanding applications. Its high tensile and yield strength, impact toughness, fatigue strength, hardness, creep resistance, and corrosion resistance contribute to its reliability, durability, and performance in various industries.
Whether in the wastewater treatment industry or pure water processing, Super Duplex 2507 stainless steel proves to be a reliable and robust material.
By utilizing Super Duplex 2507 stainless steel grades, YASA can ensure the longevity, reliability, and efficiency of their water and wastewater treatment processes.
For more information you can get in touch with our team.
FAQs about Super Duplex 2507 Stainless Steel
Q1: What is the composition of Super Duplex 2507 stainless steel?
A1: Super Duplex 2507 stainless steel contains approximately 25% chromium, 7% nickel, 4% molybdenum, and 0.25% nitrogen, along with other elements like copper and tungsten.
Q2: What are the typical tensile strength and yield strength of Super Duplex 2507 stainless steel?
A2: Super Duplex 2507 stainless steel typically has a minimum tensile strength of 750 MPa (109 ksi) and a minimum yield strength of 550 MPa (80 ksi).
Q3: Does Super Duplex 2507 stainless steel have good impact toughness?
A3: Yes, Super Duplex 2507 stainless steel exhibits excellent impact toughness, allowing it to withstand sudden loads without fracturing.
Q4: Is Super Duplex 2507 stainless steel resistant to corrosion?
A4: Yes, Super Duplex 2507 stainless steel offers outstanding corrosion resistance, making it suitable for corrosive environments, including chloride-containing media.
Q5: What is the hardness range of Super Duplex 2507 stainless steel?
A5: The hardness of Super Duplex 2507 stainless steel typically ranges from 250 to 290 HB (Brinell hardness).