Characteristics of ASTM A182 F51 Forged Steel Flange

ASTM A182 F51 Forged Steel Flange is a duplex stainless steel flange. Flange is a part that connects the shaft to the shaft and is used to connect the ends of the pipe. Flange is also used on the inlet and outlet of equipment to connect the two devices.

ASTM A182 F51 is an American standard stainless steel material. It is a Ferrite-Austenitic stainless steel. The ideal metallographic structure of duplex stainless steels is 50% ferrite and 50% austenite respectively. Generally, the minimum phase content should reach 30%. It has the advantages of both austenitic stainless steels and ferritic stainless steels.  Austenitic stainless steels have no or weak magnetic field, while duplex steels are magnetic. Duplex stainless steel is characterized by both stainless steel and carbon steel. It combines the beneficial properties of ferrite and austenite, has good resistance to chloride ion stress corrosion and sulfide stress corrosion as well as high mechanical strength.

A182 is a standard specification of the American Society for Testing and Materials (ASTM). A182 F51 forged steel flanges are manufactured in accordance with this standard, which has strict regulations on the chemical composition, mechanical properties, manufacturing process, etc. of the flange to ensure its reliability and safety in various industrial applications.

Specification of ASTM A182 F51 Forged Steel Flange

Chemical Requirements of ASTM A182 F51 Grade

Chromium is one of the most important alloying elements in ASTM A 182 F51 forged steel flange. It can form a dense oxide film on the surface of the steel, that is, a passivation film. This film can prevent further contact between oxygen and moisture and the steel matrix, thereby significantly improving the Corrosion resistance of steel.

Mechanical Property of ASTM A182 F51 Grade

Due to its unique chemical composition and duplex structure, ASTM A182 F51 flange has high strength. Its yield strength and tensile strength are relatively high, and it can withstand greater pressure and load.

Pressure Rating of ASTM A182 F51 Flange

Difference between Duplex Stainless and Austenitic Stainless:

●Sufficient plasticity toughness for forming: Yield strength is more than twice as high as that of common austenitic stainless steel, and it has sufficient plastic toughness for forming. The wall thickness of tanks or pressure vessels made of duplex stainless steel is 30-50% less than that of commonly used austenite, which helps to reduce costs. 

●The stress corrosion: It has excellent resistance to stress corrosion cracking. Even duplex stainless steels with the lowest amount of alloys have higher resistance to stress corrosion cracking than austenitic stainless steels, especially in the environment containing chloride ions. 

●The corrosion resistance: The corrosion resistance of duplex stainless steel is better than that of common austenitic stainless steel in many media. Super duplex stainless steel has extremely high corrosion resistance. 

●Engineering significance: It has lower linear expansion coefficient than austenitic stainless steel and is close to carbon steel. It is suitable for connecting with carbon steel and has important engineering significance, such as producing composite plates and linings. 

●Impact Resistance: Compared with austenitic stainless steel, duplex stainless steel has higher energy absorption capacity under dynamic or static load. It has obvious advantages in coping with unexpected accidents such as impact, and has practical application value.

Applications of ASTM A182 F51 Flange

A182 F51 flange has a high PREN value, which means it has excellent pitting resistance in corrosive environments. The PREN value is calculated as follows: PREN = %Cr + 3.3(%Mo + %W) + 16(%N), where Cr, Mo, W and N represent the contents of chromium, molybdenum, tungsten and nitrogen in stainless steel, respectively. According to the ASTM A182 F51 standard, the PREN value of the material must be greater than or equal to 34.

This makes the A182 F51 flange particularly suitable for the following corrosive environments:

Petroleum industry: During oil extraction, refining and transportation, equipment is often exposed to environments containing corrosive media such as sulfides and chlorides. The corrosion resistance of the A182 F51 flange can effectively extend the service life of the equipment.

Chemical industry: In chemical production, many media are highly corrosive, such as acid and alkali liquids, salt water, etc. The corrosion resistance of the A182 F51 weld neck flange makes it an ideal choice in these environments.

We(Shanghai Zhucheng Pipe Fittings Manufacturing Co Ltd) is professional engaged in manufacture of Steel pipe(seamless/welded), pipe fittings(butt welding, socket weld, threaded) and flanges in pipe system of all kinds of materials(carbon steel, stainless steel, alloy steel, low temp steel, pipeline steel).  In order to get to a successful cooperation with customers, normally we are willing to provide free samples to all customers if required. (The customer should be responsible for the freight and the samples should be in common size and materials)