Flange is a common pipe connection fitting, widely used in the fields of petroleum, chemical industry, electricity, water supply, HVAC, etc. The function of flange is to connect pipes or equipment and provide sealing and fixing functions. There are many types of flanges, depending on the connection method. Among them, socket weld flange, as an important connection method, is widely used in many projects due to its unique design and connection performance. So, what is a socket weld flange? What are its characteristics, advantages and applications? This article will introduce the basic concepts, construction, installation methods, and application scope of socket weld flange in detail.
What is a socket weld flange?
Socket weld flange, also known as socket weld flange, refers to a flange with a groove (socket) in the inner hole, which is used to insert the pipe into the socket part of the flange, and then fix and seal it by welding. Its characteristic is that the end of the pipe is inserted into the socket of the flange, and the welding produces an internal and external double-sided welded joint, thereby enhancing the strength and sealing performance of the connection.
Socket weld flange is mainly used for the connection of small-diameter (usually DN50 to DN200) pipes. Due to its simple and reliable connection method, it is widely used in pipeline systems with high pressure and high sealing requirements.
Construction of socket welding flange
The socket welding flange consists of several main parts:
1. Flange: This is the main part of the flange, usually round or other standard shapes, used to connect other pipe fittings or equipment.
2. Socket part: This is the part where the flange connects to the pipe, usually a groove, and the end of the pipe needs to be inserted into the groove. The design of this socket part ensures a tight fit between the pipe and the flange.
3. Bolt holes: There are usually several bolt holes around the flange to connect the flange on the other side to ensure the stability of the connection at both ends.
4. Sealing surface: The sealing surface of the flange is an important part of the sealing in the pipeline system. There are usually flat seals, convex seals or other sealing designs to ensure that there is no leakage under pressure.
5. Welded joint: The joint between the pipe and the flange is welded by socket welding. During welding, the end of the pipe is inserted into the socket part of the flange and then fixed by welding to form a strong and sealed connection.
Welding method of socket welding flange
The welding method of socket welding flange is relatively simple, mainly divided into the following steps:
1. Pipe port processing: First, the pipe needs to be cut to ensure that the cut surface is flat, free of burrs and rust.
2. Pipe insertion into flange socket: Insert one end of the pipe into the socket part of the flange to ensure that the end face of the pipe is flush with the socket face of the flange. The insertion depth is usually 1-2 times the outer diameter of the pipe.
3. Positioning and fixing: After the pipe is inserted into the flange, the relative position of the pipe and the flange must be stable through the positioning tool, and the temporary fixing device must be used to ensure that no displacement occurs during the welding process.
4. Welding: After the pipe is inserted into the flange socket and fixed, socket welding is performed. Welding is generally performed on the outside and inside of the pipe at the same time to form a double-sided welded joint to enhance the strength of the connection.
5. Inspection and cleaning: After welding is completed, the quality of the weld needs to be checked to ensure that there are no defects such as cracks and pores. At the same time, clean the residue in the welding area to ensure sealing performance.
Advantages and Disadvantages of Socket Weld Flanges
Socket weld flanges have been widely used in many occasions due to their unique welding method and connection performance. The advantages and disadvantages of socket weld flanges will be analyzed in detail below.
Advantages
1. High sealing: Socket weld flanges are welded on both sides inside and outside, making the connection between the pipe and the flange tighter, thereby improving the sealing. This is especially important for pipeline systems that require high sealing and high pressure resistance.
2. High welding strength: Since the welding part is double-sided welding, the welding strength of the socket weld flange is higher and more durable than the flange welded on one side.
3. Suitable for high-pressure pipelines: Socket weld flanges are widely used in pipeline systems with higher pressure, especially for small-diameter high-pressure pipelines, and can withstand greater working pressure.
4. Easy installation: Although socket weld flanges require welding, their installation process is relatively simple, reducing other complex connection processes. During installation, the pipe only needs to be inserted into the flange socket and fixed by welding.
5. Reduce the risk of leakage: The pipe connected by socket welding is in close contact with the flange, and it is not easy to leak, which is suitable for occasions requiring high sealing.
Disadvantages
1. Limitation of pipe size: Socket weld flange is generally suitable for small diameter (DN50 to DN200) pipes, but not for large diameter pipes. Large diameter pipes are more commonly used with butt welding flanges or flat welding flanges.
2. High welding quality requirements: The quality of the welding part is crucial to the performance of the socket welding flange. If the welding process is unqualified, it may cause leakage or flange loosening, affecting the stability and safety of the pipeline system.
3. Not suitable for occasions where frequent disassembly is required: Since the socket welding flange is fixed by welding, disassembly and maintenance are relatively inconvenient, it is not suitable for systems that require frequent disassembly and maintenance.
4. The welding process requires a high level of technology: The welding of the socket welding flange requires certain technical requirements, and unqualified welding quality will result in a loose connection, affecting the safety of the entire pipeline system.
Application fields of socket weld flange
Socket weld flange is widely used in pipeline systems with high pressure and good sealing performance. Its main application fields include:
1. Petroleum and chemical industry: Socket weld flange is often used for pipeline connection in fields such as petroleum, natural gas, chemical plants, etc., especially in places where high pressure and high sealing are required.
2. Power industry: Socket weld flange is widely used in high temperature and high pressure systems such as boilers, steam pipes, cooling water pipes, etc. in power plants.
3. Water supply and drainage system: In municipal water supply, sewage treatment and other systems, socket weld flange is widely used for high pressure pipeline connection due to its reliable sealing and welding strength.
4. Shipbuilding and marine engineering: In fields such as ships and offshore platforms, socket weld flange is widely used in various pipeline systems due to its characteristics suitable for high pressure environment.
Socket weld flange is a high sealing and high strength pipeline connection method with the advantages of easy installation, good sealing and high welding strength, and is suitable for pipeline systems with high pressure. Although socket weld flange has certain requirements in welding technology and disassembly, it is widely used in fields such as petroleum, chemical industry, power, and shipbuilding. Understanding the characteristics and advantages of socket welding flanges will help make the right choices in piping system design and construction, ensuring the stable, safe and efficient operation of the piping system.
