What is a flat welding flange?

Flat welding flange, also known as lap welding flange. The connection between flat welding flanges and pipes is achieved by first inserting the pipe into the flange hole to the appropriate position, and then welding it together. Its advantage is that it is easier to align during welding and assembly, and the price is cheap, so it has been widely used.

According to internal pressure calculation, the strength of a flat welding flange is about two-thirds of that of a corresponding butt welding flange, and the fatigue life is about one-third of that of a butt welding flange. Therefore, flat welding flanges are only suitable for pipeline systems with relatively low pressure levels, where pressure fluctuations, vibrations, and oscillations are not severe.

Flat welding flanges can be further divided into two types: neck flat welding and plate flat welding.