Nozzle Flanges for Vessels & Equipment

They were built with pressure vessel and tank fabricators in mind. The idea behind them is simple: instead of welding a standard weld neck flange and a piece of pipe together separately, you get one solid piece that does both jobs. That single-piece construction, and the weld it eliminates, is really what sets this flange style apart.

Most long weld necks have a straight-through bore with a square-cut end rather than the beveled end you'd see on a typical weld neck. The bore is usually matched to the nominal pipe size, but it can be adjusted to fit your needs. The overall length is also flexible and the nozzle body can be made to standard sizes or custom lengths depending on how much additional reinforcement your application calls for. You'll also notice a small radius where the neck meets the flange base; that's not just cosmetic, as it smooths out what would otherwise be an abrupt 90-degree transition and reinforces the integrity of the one-piece design.

Under ASME B16.5 subsection 2.8, these are officially referred to as "straight hub welding flanges," though the spec doesn't go into a lot of detail on them. That's largely because long weld necks are so application-specific - the right one depends on the pressure, temperature, and media your vessel is handling, so there's no one-size-fits-all standard to write to.

Beyond standard long weld necks, Texas Flange also carries reinforced barrel flanges in nozzle form for situations where you need a heavier-duty outlet connection. Wall thickness can be specified to match your requirements. Reach out to us with your application details. We stock and source nozzle flanges in all major material grades, including carbon steel, stainless, and nickel alloys.