Slip-On Flanges slide over the end of piping and are welded into place. They typically have a raised or flat face, with an inside diameter that is only slightly larger than the pipe’s outer diameter.
With a tapered hub for additional reinforcement, Weld Neck Flanges are used for the severe service conditions of extremely high or extremely low temperatures, or high pressure. In order to transfer stress from the flange to the pipe, these flanges are attached by welding the pipe to the flange neck.
Similar to standard weld neck flanges, the Long Weld Neck Flange is often used as a nozzle for a column or barrel. With a longer neck than the standard weld neck, this flange is known to offer simple connectivity with other pipes.
Commonly used on high pressure pipes of smaller sizes, Socket Weld Flanges are stronger than double welding a slip-on flange. For a better flow of gas or fluid inside the pipe and a smooth bore, these flanges are attached by inserting the pipe into the socket end and applying filled weld to the top.
Blind Flanges are commonly used to seal the end of pressure vessel openings or piping systems. Because the maximum stresses in blind flanges are bending stresses at the center, they can handle high stress from bolt loading and internal pressure.
To maintain B16.5 rating on a modified blind flange, a hub is required. A “high hub” provides extra material for machining.
Threaded Flanges can be assembled without welding and are used for special applications. They are similar to slip-on flanges. However, the bore of the Threaded Flange has tapered threads. They are often used for high pressure requirements and other special applications where strength is essential.
Used with lap joint stubs, Lap Joint Flanges slide directly over the pipe. They are mostly used for low alloy steel or carbon piping systems that are regularly dismantled for cleaning or inspection purposes.
RTJ Flanges are made to accept steel ring gaskets into their grooves in order to create a metal to metal seal. This happens when tightened bolts compress the gasket into the grooves between the flanges.
Used with orifice meters for measuring the flow rate of gases or liquids in a pipeline, Orifice Flanges are similar to slip on flanges or weld neck flanges but have extra machining. This extra machining adds pairs of pressure “Tappings” directly opposite each other, making separate orifice tappings or carriers in the pipe wall unneeded.