Flange connection methods

24 Jul,2025

1. Concept of Flange

A flange is a disc-shaped structure used to connect two pipes, equipment, or components, connected by fasteners such as bolts. It is widely used in various industrial fields such as petroleum, chemical, and power industries.

2. Main Connection Methods of Flanges

1. Slip-on Flange Connection: The slip-on flange is the most common connection method, suitable for low-pressure pipelines or non-critical connections. It connects the flange to the pipe by welding, then bolts are used to connect the two flanges.
2. Butt Weld Flange Connection: Butt weld flanges are suitable for environments with high pressure, high temperature, or corrosive media. This connection method requires the flange and pipe to be made of the same material and joined by welding the two flanges together.
3. Threaded Flange Connection: Threaded flange connections are suitable for small-diameter, low-pressure pipelines. They connect through threads on the flange, providing good sealing performance after tightening.
4. Blind Flange Connection: Blind flanges are mainly used to close one end of a pipeline or equipment for maintenance or other operations. They are bolted at the position to be closed, featuring a simple installation and removal process.

3. Characteristics of Flange Connections

Flange connections have advantages such as easy installation, simple disassembly, and good sealing. They are suitable for various media, pressure, and temperature ranges, allowing different connection methods to be chosen according to actual needs. Additionally, flange connections have good reusability, reducing costs.

4. Practical Applications

In industrial fields such as petroleum, chemical, and power, flange connections are widely used for connecting various pipes, valves, pumps, and other equipment. For example, in oil drilling, flange connections are used to connect oil pipes, water pipes, and various equipment; in chemical production, flange connections are used to connect reactors, storage tanks, etc.

5. Summary

Flange connection methods have wide applications in the industrial field. Different connection methods are suitable for different scenarios, such as slip-on flanges, butt weld flanges, threaded flanges, and blind flanges. Choosing the appropriate connection method is crucial to ensure the normal operation of pipelines and equipment. Therefore, in practical applications, selection should be based on factors such as pressure, temperature, and media to ensure safety and efficiency.