The difference between neck flat welding flange and neck butt welding flange

These two flanges are commonly used flanges

一、 They are structured differently
1. Slip-on flange with neck: It is a flange that extends steel pipes, fittings, etc. into the flange and connects it to equipment or pipelines through fillet welds.
2. Neck butt welding flange: a flange with a neck and a round pipe transition and connected to the pipe by butt welding.

二、the scope of application is different
1. Slip-on flange with neck: There is a short neck, which increases the strength of the flange and improves the bearing strength of the flange. So it can be used on higher pressure pipelines.
2. Neck butt welding flange: suitable for pipelines with large fluctuations in pressure or temperature or high-temperature, high-pressure and low-temperature pipelines, used for the connection of pipelines and valves with PN greater than 2.5MPa; also used to transport expensive and flammable , Explosive medium pipeline.

三、 Different forms of welds
1. Neck flat welding flange: The welding seam between the neck flat welding flange pipe and the flange is a fillet weld.
2. Neck butt welding flange: The welding seam between the neck butt welding flange and the pipe is a ring weld.

四、The pressure is different
The pressure of the welded butt flange with neck is higher than that of the flat welded flange with neck. If the pressure you use is too high, it is recommended to use the butt welded flange