EN 1092-1 12B DN500 PN10-100 ANSI Flange

Comparison with butt welding flanges

Compared to Weld Neck (WN) flanges, SO flanges are cheaper and faster to install but offer inferior fatigue and stress resistance. WN flanges are for critical service, while SO flanges are a more economical solution for stable, low-pressure conditions. The choice depends on specific application needs, budget, and safety codes.