Butt Weld Flanges Butt Weld 4-Bolt Flanges DMIC’s ‘FBW’ Butt Weld flanges can produce exquisite welded piping assemblies in the hands of master welders. However, the possibility of leakage and failure is increased at pressure relative to our ‘FWI’ Socket Weld series. If in doubt, please order the ‘FWI’ Socket Weld model. Poorly made butt-weld connections are a safety hazard. Features Sizes from ½” through 4″ Extensive stock of “Standard” and “Companion” types “Standard” model with groove Includes premium Buna-N O-Ring Model Selector ‘FBWSL’ – Butt Weld, Standard, C.61 (3,000 PSI) ‘FBWSH’ – Butt Weld, Standard, C.62 (6,000 PSI) ‘FWIEL’ – 90° Elbow Deep Skt Weld, Standard, C.61 (3,000 PSI) ‘FBWCH’ – Butt Weld, Companion, C.62 (6,000 PSI) Download Butt Weld PDF