1. The flange of pressure vessel can be divided into general flange and reverse flange according to the overall structure of flange.
2. According to the type of flange gasket arrangement, we can divide it into narrow face flange and wide face flange.
a. Narrow face flange refers to the gasket contact surface, located in the flange bolt hole surrounded by the circumference of the flange, narrow face flange is the most widely used flange.
b. The wide face flange is the contact surface of gasket, which is distributed on both sides of flange bolt center circle. Generally, the wide face flange can only be used in the situation of low pressure.
3. According to the integrity of each part of flange, we can divide it into loose flange, integral flange and arbitrary flange.
a. Loose flange is the flange can not be effectively connected with the container as a whole. In the calculation, we can think that the cylinder and the flange ring will not bear the flange moment together, and the flange itself will not bear the flange moment.
b. Integral flange refers to the flange ring, neck and barrel which can be effectively connected into a whole flange, which will bear the flange torque together.
C. any flange refers to the flange between the upper two flange to the whole extent of the flange. Although the cylinder does not form an integral structure with the flange ring, it can be used as a structural element to bear the flange torque together. The flat welding flange belongs to this type of flange.
4. according to the connection of flange and cylinder, we can divide the flange into looped flange and threaded connection flange, socket welding flange, flat welding flange and butt welding flange.
5. in the standard of pressure vessel, we can divide the flange into three types: A-type flat welding flange, B flat welding flange and long neck butt welding flange.
