Application difference of flanges under petrochemical standard classification

According to petrochemical standards, flanges can generally be divided into the following five types: flat welding flange, butt welding flange, socket welding flange, loose sleeve flange and threaded flange.

The flat welding flange is simple in structure and uses less materials when making, but its rigidity and sealing property are not as good as the butt welding flange. It is widely used in the connection of medium and low pressure vessels and pipes.

EN 1092 Q235 FF flat flanges

Butt welding flange is widely used in pipeline welding. It is generally applicable to pipelines with large fluctuations in pressure or temperature, as well as high-temperature, high-pressure and low-temperature pipelines. It is also applicable to pipelines conveying expensive, flammable and explosive media.

Weld neck flanges WN flanges A182 Gr F347 RTJ ASME B16.5

The socket welding flange has good rigidity, small welding deformation and good sealing performance, and can be used for occasions with pressure of 1.0 ~ 10.0MPa.

ANSI B16.5 socket welding flanges

The loose flange is not in contact with the medium, so it is convenient to disassemble and assemble the pipeline. It is applicable to the connection of non-ferrous metals such as steel, aluminum and stainless and acid resistant steel vessels and corrosion-resistant pipelines.

Lap joint flange or loose flange finished in Haihao Group

Compared with plain welding flange or butt welding flange, threaded flange is convenient for installation and maintenance, and can be used on some pipelines that are not allowed to be welded on site.

Galvanized Threaded Flanges

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