Flange pup joints are components used to connect pipes, which can connect different pipes together or connect pipes and equipment. It consists of flanges, sealing gaskets, bolts and nuts. Flange pup joints have the characteristics of simple structure, easy installation and good sealing performance, and are widely used in chemical, petroleum, electric power, water treatment and other industrial fields.
Standard specifications are an important guarantee for ensuring the quality of flange pup joints. Only by complying with standard specifications can we ensure that the dimensions, materials, processing technology and other aspects of flange pup joints meet the requirements, thereby ensuring its safety, stability and reliability during use. So what are the standards for flange pup joints?

Standards for flange pup joints
1. International standards
Flange pup joints are a common connector for connecting pipes to equipment, valve and other pipes. Internationally, the standard for flange pup joints is ISO 7005.2-1998, which specifies the flange dimensions of different models and the connection methods between flanges.
2. American standards
The American pipeline industry also has a set of regulations on the dimensions, materials and connection methods of flange pup joints. ASME B16.5 is the representative of the American flange pup joints standard. This standard specifies the flange size, nominal pressure and connection method of different types, and makes detailed provisions and requirements for flange pup joint materials.
3. European standards
The European standard for flange pup joints is EN 1092-1, which clearly stipulates the size, nominal pressure and connection method of flange pup joints and makes specific instructions and requirements for the materials of flange pup joints.

Types and materials of flange pup joints
According to different working conditions, flange pup joints are divided into stainless steel flange pup joints, carbon steel flange pup joints, alloy steel flange pup joints, corrosion-resistant steel flange pup joints, plastic flange pup joints and glass fiber reinforced plastic flange pup joints. When purchasing, it is necessary to select the appropriate material according to the actual situation.

Connection method of flange pup joints
The connection methods of flange pup joints include welding connection, bolt connection, tap connection, etc. Among them, bolt connection is the most commonly used connection method, which can easily realize quick installation and disassembly, and is suitable for flange pup joints of different models and materials.

Summary
As an important part of pipeline connectors, the standardization of flange pup joints is crucial to the safety and quality of pipeline projects. This article introduces the provisions of international standards, American standards and European standards on flange pup joints in terms of size, material, connection method, etc., and briefly introduces flange pup joints of different types and materials.