ANSI Flange

The American National Standards Institute (ANSI) calls for the use of an to be used on specific applications. The is a three-part flange consisting of one flat flange, one flange machined to take a rubber O-ring and the rubber O-ring.

The American National Standard Institute, ANSI, has been overseeing guidelines and standards for products manufactured through several sectors. ANSI-approved flanges are used for the industrial market which handles gas, air and steam process systems.


Flanges are used to attach a series of pipes or other flanges together. Some flanges, such as in the oil and gas sector, are required to sustain under high amounts of pressure. ASNI provides standards to flange manufactures to test flanges before they can be marketed to a particular sector.


ANSI provides standards on flanges depending upon pressure in pounds per second per inch (PSI), according to size in inches of the flange. Pressure and size are dependent upon whether the flange is welded to the pipe, threaded or bolted.


Depending on the material the flange is made from, such as cast iron or steel, and the type of threaded material used for fittings, every flange is designated to a particular class. From these class ratings, several requirements, such as pressure-temperature rating, bolt and nut dimensions, coating material and several other factors, make up the standards according to the flange characteristics.

Welding Neck Flanges,


Slip-on flange


Blind Flanges, BL Flange, BLRF