Standard classification of stainless steel flanges

The standard classification of stainless steel flanges can be explained from multiple perspectives, mainly including international or regional standards, pressure levels, connection methods and materials. The following is a detailed summary of the standard classification of stainless steel flanges:

First, international or regional standards

Chinese standard (GB):

For example, GB9112-88 (GB9113·1-88~GB9123·36-88) or GB/T9112-2010 (GB9113·1-2010~GB9123·4-2010), these standards specify the size, connection method, sealing form, material and other requirements of stainless steel flanges.

American standard (ANSI):

For example, ANSI B16.5 and ANSI 16.47 Class150, 300, 600, 900, 1500 (TH, LJ, SW), these standards are widely used in the United States and countries and regions that adopt American standards.

Japanese Standard (JIS):

For example, JIS 5K, 10K, 16K, 20K (PL, SO, BL), these standards are applicable to Japan and countries and regions that adopt Japanese standards.

German Standard (DIN):

For example, DIN2527, 2543, 2545, 2566, 2572, 2573, 2576, 2631, 2632, 2633, 2634, 2638 (PL, SO, WN, BL, TH), these standards are authoritative in Germany and countries and regions that adopt German standards.

Italian Standard (UNI):

For example, UNI2276, 2277, 2278, 6083, 6084, 6088, 6089, 2299, 2280, 2281, 2282, 2283 (PL, SO, WN, BL, TH), these standards are used in Italy and countries and regions that adopt Italian standards.

British Standards (BS):

For example, BS4504, 4506, these standards are recognized in the UK and countries and regions that adopt British standards.

Chemical Industry Ministry Standards (HG):

For example, HG5010-52~HG5028-58, HGJ44-91~HGJ65-91, HG20592-97 series, HG20615-97 series, etc. These standards are instructive in China’s chemical industry.

Machinery Ministry Standards (JB):

For example, JB81-59~JB86-59, JB/T79-94~JB/T86-94, etc. These standards are authoritative in China’s machinery industry.

Pressure Vessel Standards:

For example, JB1157-82~JB1160-82, JB4700-2000~JB4707-2000, etc. These standards are formulated for the field of pressure vessels.

Marine flange standards:

For example, GB/T11694-94, GB/T3766-1996, etc. These standards are applicable to the shipbuilding industry.

Second, pressure level

The pressure level of stainless steel flanges is also an important basis for classification, usually expressed as PN (nominal pressure) or Class (pressure level), such as PN2.5~PN160 or Class150, 300, 600, 900, 1500, etc. Stainless steel flanges of different pressure levels are suitable for pipeline systems with different pressure requirements.

Third, connection method

According to different connection methods, stainless steel flanges can be divided into many types, such as:

Flat welding flange: The pipe must be inserted into the inner ring of the flange for welding.

Butt welding flange: A flange with a neck, a smooth transition section, and a butt welding connection with the pipe.

Socket welding flange: A flange with a socket and a socket welding connection with the pipe.

Threaded flange: A flange with a thread and a threaded connection with the pipe.

Loose flange: a flange that is slid onto a pipe and used in combination with a flanged nipple or a welded ring.

Special flange: non-circular flanges such as diamond flanges and square flanges.

Reducing flange: a flange that is connected to a standard flange, but the nominal diameter of the pipe is smaller than the nominal diameter of the standard flange pipe.

Full-plane flange: a flange whose sealing surface is in the same plane as the entire flange surface.

Boss flange: a flange whose sealing surface is slightly higher than the entire flange surface.

Concave-convex flange: a pair of flanges, one of which has a concave sealing surface and the other has a convex sealing surface.

Tenon-groove flange: a pair of flanges, one with a tenon and the other with a groove that matches the tenon.

Ring-joint flange: the sealing surface of the flange is a trapezoidal ring groove.

Stainless steel flange cover: a round plate with bolt holes that is connected to the pipe end flange and closes the pipe.

Fourth, material

Stainless steel flanges are made of various materials, including 304, 304L, 316, 316L and other common stainless steel materials. These materials have different corrosion resistance and mechanical properties, and can be selected according to the specific use environment and requirements.

In summary, the standard classification of stainless steel flanges can be explained from multiple perspectives such as international or regional standards, pressure levels, connection methods and materials. In practical applications, it is necessary to select the appropriate stainless steel flange type and specifications according to the specific use requirements and characteristics of the pipeline system.