A weldneck flange also known as a high-hub flange and tapered hub flange is a type of flange. There are two designs. The regular type is used with pipes. The long type is unsuitable for pipes and is used in process plant. A weld neck flange consists of a circular fitting with a protruding rim around the circumference. Generally machined from a forging, these flanges are typically butt welded to a pipe. The rim has a series of drilled holes that permit the flange to be affixed to another flange with bolts.
Weld Neck Flanges have a long tapered hub and are often used for high pressure applications. When ordering a weld neck flange, it is important to specify the schedule pipe is being used for. This is because the inside diameter of the flange will match the inside diameter of your pipe. The buttweld joint this flange has with the pipe along with the tapered hub, makes this flange very resistant to dishing and a very sturdy connection. These flanges are ideal for extreme fluctuations of temperature and in environments where there may be a lot of bending and handling of the flanges.
These pipe flanges attach by welding the pipe to the neck of the flange. This transfers stress from the flange to the pipe instead. It also reduces the stress concentration from the base of the hub. Weld neck flanges are often used for applications where high pressure is a factor. The inside diameter of the flange is designed to match the pipe's inside diameter. Weld Neck Pipe flanges with a hub have published specifications that range from 1/2" thru 96". Our company provides these in all material grades, specifications and sizes.
Weld neck pipe flanges are typically provided with a raised face, flat face, or RTJ facing. When a raised face is necessary for weld neck pipe flanges, the standard height is 1/16" for weld neck pipe flanges under 400#. For weld neck pipe flanges of 400# and up, the standard weld neck pipe flange raised face height is 1/4".
Coastal Flange manufactures weld neck pipe flanges in all steel material grades, including carbon weld neck pipe flanges, stainless steel weld neck pipe flanges and alloy weld neck pipe flanges. Coastal Flange also has many different weld neck pipe flanges in stock and ready to ship. Weld neck pipe flanges in stock include ANSI B16.5 weld neck pipe flanges, ASME B16.47 Series "A" weld neck pipe flanges, ASME B16.47 Series "B" weld neck pipe flanges, Pressure Vessel weld neck pipe flanges. Coastal Flanges also manufactures custom weld neck pipe flanges per customer requirements.