Haihao Group has successfully delivered a batch of weld neck (WN) flanges with RTJ facing to a valued customer in Singapore. The product details are as follows: Product: WN Flange RTJ; Size: 1″; Rating: 2500#; Schedule: S-80S; Standard: ASME B16.5; Material: ASTM A182 F55 (Super Duplex Stainless Steel, UNS S32750 / F53); Finish: Supplied without painting
The A182 F55 / S32750 / F53 super duplex stainless steel used in this project ensures outstanding performance in aggressive environments. With a pitting resistance equivalent number (PREN) ≥ 40, the flange offers superior resistance against pitting, crevice, and chloride-induced corrosion, making it highly reliable for offshore, oil & gas, and chemical processing industries.
The material’s duplex microstructure balances ferrite (35–55%) and austenite phases, providing both exceptional strength and excellent corrosion resistance. This ensures longer service life compared with standard stainless steels.

