ANSI B16.5 – Pipe Flanges and Flanged Fittings

ANSI B16.5 is an international standard issued by the American National Standards Institute (ANSI), which regulates the dimensions, materials, connection methods and performance requirements of pipes, valves, flanges and fittings. This standard specifies the standard dimensions of steel pipe flanges and flanged joint assemblies, applicable to piping systems for general industrial use.

The following are the main contents of the ANSI B16.5 international standard:

Flange classification:

Welding neck flange, Slip on hubbed flange, Slip on plate flange,Blind flange, Socket welding flange, Threaded flange, Lap Joint flange

Flange size and pressure class:
ANSI B16.5 specifies steel flanges of different size ranges and pressure classes, including
Nominal diameter NPS1/2 inch-NPS24 inch, namely DN15-DN600;
Flange class 150, 300, 600, 900, 1500 and 2500 classes.

Flange surface type:

The standard covers various surface types such as flat flange, flange flange, concave flange, tongue flange, and groove flange.

Flange material:

ANSI B16.5 lists flange materials suitable for different working conditions, such as carbon steel, stainless steel, alloy steel, etc.

For example: Aluminum 6061, Aluminum 6063, Aluminum 5083;
Stainless steel 304 304L 316 316L 321 316Ti 904L;
Carbon steel grade for flanges: Q235/S235JR/ST37-2/SS400/A105/P245GH/ P265GH / A350LF2.

Flange connection:

The standard describes the flange connection method in detail, including the number of bolt holes, the diameter of the bolt holes, and bolt specifications.

Flange sealing:

Standardize the shape of the sealing surface of the flange and the selection of sealant to ensure the reliability and sealing performance of the connection.

Flange testing and inspection:

The standard covers testing and inspection requirements for flanges, including visual inspection, dimensional inspection, material acceptance, and pressure testing.

Flange marking and packaging:

Specifies the marking method and packaging requirements of flanges, so that the flanges can be correctly identified and protected during transportation and use.

Application:

The ANSI B16.5 standard has a wide range of applications and is suitable for pipeline systems in industries such as petroleum, natural gas, chemical industry, electric power, papermaking, shipbuilding, and construction.


Post time: Aug-01-2023