1. Plate-type flat welding flange. GOST 12820-80 FLANGE tells you that plate type flat welding flange (chemical standard HG20592, national standard GB/T9119, mechanical JB/T81). GOST 12820-80 FLANGE tells you that its advantages are that it is easy to obtain, simple to manufacture, low cost, and widely used.

GOST 12820-80 FLANGE tells you that, however, its rigidity is poor, so it should not be used in chemical process piping systems and high and extremely hazardous occasions with supply and demand, flammable, explosive, and high vacuum requirements. The sealing surface types are flat and raised.
2. Flat welding flange with the neck. GOST 12820-80 FLANGE tells you that flat welding flanges with necks belong to the national standard flange system. It is one of the manifestations of the national standard flange (also known as GB flange) and is one of the commonly used flanges on equipment or pipelines.
advantage. GOST 12820-80 FLANGE tells you that its on-site installation is more convenient, and the process of slapping and rubbing the welding seam can be omitted
However, GOST 12820-80 FLANGE tells you that the neck height of the flat welding flange with the neck is lower, which improves the stiffness and load-bearing capacity of the flange. Compared with butt welding flanges, the welding workload is large, the consumption of welding rods is high, and it cannot withstand high temperature and high pressure repeated bending and temperature fluctuations.
The above information is the GOST 12820-80 FLANGE manufacturer's introduction and analysis of the advantages and precautions of the flange, hope it helps you.