DUPLEX stainless steel flanges are pipe connecting components made from duplex stainless steel, used for connections between pipes or between pipes and equipment. Here is a detailed introduction about them:

raw materials

The raw material for duplex stainless steel flanges is duplex stainless steel, which has approximately equal proportions of austenite and ferrite phases in its solid solution, with the minor phase content generally required to reach 30%. Under low carbon conditions, the chromium content ranges from 18% to 28%, while the nickel content ranges from 3% to 10%. Some grades also contain alloying elements such as molybdenum, copper, niobium, titanium, and nitrogen. Commonly used duplex stainless steel materials include S32205 (2205, F60), S31803 (F51), S32750 (2507, F53), and S32760 (F55).

production standard

There are numerous production standards for duplex stainless steel flanges, including the national standard GB/T series, the mechanical industry standard JB/T series, the chemical industry standard HG/T series, and the American standard ASME/ANSI B16.5, among others. Different types of flanges correspond to different standards, such as flat welding flanges conforming to GB/T9119-2000 and other standards, and necked flat welding flanges conforming to GB/T9116-2000 and other standards.

performance advantage

High strength: The yield strength is more than double that of ordinary austenitic stainless steel, with sufficient plasticity and toughness to meet the strength requirements of various engineering structures.

Corrosion Resistance: It exhibits excellent resistance to stress corrosion cracking, particularly outstanding in chloride environments, while also surpassing austenitic stainless steels with comparable alloy content in terms of pitting corrosion, wear corrosion, and fatigue corrosion resistance.

High-temperature resistance: It maintains excellent mechanical and corrosion-resistant properties at elevated temperatures, making it suitable for pipeline systems in high-temperature working conditions.

Application field

Duplex stainless steel flanges are widely used in wastewater treatment, seawater desalination, papermaking, food processing, offshore oil platforms, oil fields, and other fields. They exhibit excellent adaptability in various corrosive media such as acids, alkalis, and seawater, effectively reducing product replacement costs and labor expenses while offering high cost performance.

Specification Model

The specifications and models of duplex stainless steel flanges are diverse. Based on pressure ratings, they can be categorized into PN6 (0.6MPa), PN10 (1.0MPa), PN16 (1.6MPa), PN25 (2.5MPa), PN40 (4.0MPa), and others, meeting the requirements of various pressure working conditions.