Large Diameter High Pressure Forged Flanges

Large diameter high pressure forged flanges are critical components used in high-pressure piping systems, typically connecting pipes, valves, pumps, or other equipment to ensure system sealing and safety. Due to their "large diameter" and "high pressure" characteristics, these flanges must possess high strength, corrosion resistance, and high-temperature resistance, making them widely used in industries such as oil, natural gas, chemical, and power generation.

Key Features:

1. Materials: Common materials include carbon steel, stainless steel, and alloy steel (such as A105, A182 F316/F304, 20# steel, 16Mn, etc.). The appropriate material is selected based on the operating environment to withstand high pressure and corrosive media.
2. Manufacturing Process: The forging process ensures that the flange has higher strength and toughness. Compared to cast flanges, forged flanges have a denser internal structure and are suitable for high-pressure environments. The manufacturing process typically includes forging, heat treatment, machining, and inspection.
3. Specifications and Standards:
   • Large Diameter Range: Typically refers to flanges with a diameter greater than DN600 (24 inches).
   • Pressure Rating: Commonly found in high-pressure ratings such as Class 600, 900, 1500, 2500 (according to ASME standards), or PN100, PN160, etc. (according to EN standards).
   • Standards: Common standards include ASME B16.5, B16.47, API 605, EN 1092-1, GB/T 9112, etc.
4. Types: Including slip-on flanges, weld neck flanges, blind flanges, socket weld flanges, etc. Among them, weld neck flanges are more common due to their structure being suitable for high-pressure environments.
5. Applications: Used in high-pressure steam pipelines, oil and gas transmission pipelines, refining and chemical equipment, nuclear power equipment, etc., requiring the flange to withstand extreme pressure and temperature.

Design and Selection Considerations:

• Pressure-Temperature Rating: Select the appropriate flange rating based on the operating pressure and temperature of the piping system.
• Sealing Face Type: Common sealing faces include flat face (FF), raised face (RF), male and female face (MFM), ring type joint (RTJ). RTJ is suitable for higher pressure environments.
• Size and Matching: The size of the large diameter flange must match the outer diameter and wall thickness of the pipe to ensure a secure connection.
• Corrosion Protection and Durability: In corrosive environments, anti-corrosion coatings can be added, or corrosion-resistant materials such as stainless steel or nickel-based alloys can be used.

Market and Suppliers:

China is one of the major producers of large diameter high pressure forged flanges in the world. There are many professional manufacturers in Hebei, Shanxi, Jiangsu and other places. When purchasing, pay attention to the suppliers qualifications (such as ISO 9001, API certification), production capacity, and product quality inspection (such as ultrasonic testing, pressure testing).

Recent Trends:

• Technological Advancements: With the development of advanced forging technology and non-destructive testing technology, the quality and accuracy of large diameter high pressure flanges are continuously improving.
• Environmental Protection and Energy Saving: Some manufacturers are starting to use more environmentally friendly materials and production processes to meet green industry demands.
• Customization Needs: Customized design requirements are increasing for special working conditions (such as ultra-high pressure, ultra-low temperature).