Long-necked flanges, also known as LWN flanges, are similar to the standard weld neck flanges but the neck is considerably longer. This type of flange is often used as a nozzle for a barrel or a column. They can be classified later as standard type, heavy gun type, variable body type and whole body type. These flanges are kind of exclusive for the reason of their uncomplicated connectivity with other pipes. Where standard weld neck flanges are used extensively for pipes, long weld neck flanges (often abbreviated to LWN) are used in high pressure and high (or fluctuating) temperature situations primarily in the oil and gas industry. The long neck guides the pipe into the flange itself and provides reinforcement that a standard weld neck flange cannot. This reinforcement is very important for safety in high pressure industrial, commercial and even residential systems. Uses of long-necked flanges are primarily on vessels where an elongated neck is required. Long-necked flanges (LWN) are primarily utilised on vessels where an elongated neck is required. This is considered a specialty flange because of the protruding neck or hub, which acts as a boring extension. The conical collar helps reduce the thickness of the steel and appears to be a pipe extension. LWN steel flanges are used primarily in the chemical and petroleum industries, as well as in commercial and residential buildings ASME 16.47 anf asme 16.5 series of long weld flanges are used exclusively for situations in high levels of stress and fluctuating temperatures.
