Carbon Steel Stainless Steel Alloy Steel Welded Flat Weld Neck Butt Weld Flange

American standard butt weld flange for pipe connection American standard butt weld flange is a pipe fitting part that connects pipes to pipes, using a necked round pipe transition structure and butt welding connection with the pipe. Its production process includes three processing methods: forging, casting and medium plate turning, and implements ASME B16.5 and other American standard standard systems. The flange is connected by double-sided welding and bolt fastening, with the characteristics of stable rigid structure and strong deformation resistance, suitable for high-pressure and high-temperature pipeline systems with a PN value higher than 2.5MPa, and is widely used in petrochemical, power transmission and other fields. Category Pipe Fittings Manufacturing Process Forging/Casting/Turning System Implementation Standard ASME B16.5 Connection Method Butt Weld Connection Applicable Pressure PN≥2.5MPa Material Type Carbon Steel/Stainless Steel/Alloy Steel Catalog 1 Structural Characteristics 2 Manufacturing Process 3 Technical Parameters 4 Implementation Standards 5 Application Scenarios 6 Performance Comparison 7 Quality Control Structural Characteristics Broadcast Editing The transition structure of the round pipe with neck is adopted, and the welding port is far away from the sealing surface to avoid thermal deformation. According to whether it has a neck, it can be divided into two categories: with a neck type and without a neck, in which the necked flange enhances the structural strength through the neck. The sealing surface form includes protrusion (RF), concave and convex surface (MFM) and other types, which are sealed through the combination of flange and gasket and bolt. The manufacturing process includes three processing methods: forging: repeatedly forging metal billets through forging hammers to form casting: using liquid metal casting molds to form medium plate turning: using medium and thick steel plates to be precision machining by CNC machine tools, in which the forging process can improve the density of materials [3], the casting process is suitable for the production of complex structural parts, and CNC machining ensures that the flange dimensional accuracy reaches ±0.1mm. Technical parameters According to the 2025 product data: the diameter of the center circle of the bolt hole covers the range of 50mm to 2130mm, the bolt hole diameter specification is 11mm to 30mm, the flange thickness is from 12mm to 58mm, the outer diameter of the adapted pipe includes A/B, the theoretical weight range is 0.36kg to 234.6kg, the implementation standard belongs to the core products of the American standard system, the main implementation specifications include: ASME B16.5: specification flange size and pressure level ASME B16.47: suitable for large-diameter flange manufacturing standards and compatible with domestic standard systems such as GB/T (national standard) and HG (chemical industry standard) [1]. Application scenarios are suitable for three types of industrial environments: high-pressure and high-temperature pipelines: working pressure ≥ 2.5MPa working conditions [5] Low-temperature media transportation: LNG and other ultra-low temperature environments High-risk media transportation: flammable, explosive, toxic and harmful media pipelines account for 43% of applications in petrochemical plants (2025 industry statistics). Compared with traditional flat welded flanges, the performance has significant advantages: the compressive strength is increased by more than 28% [3]The welding force distribution is more uniform and the temperature fluctuation range is expanded to -196°C~600°C [4], but there are limitations such as 15%-20% increase in weight compared to flat welded flanges and the need for special equipment for installation. The quality control production process follows three core standards: Material testing: Implementation of ASTM A105 and other American material specifications Dimensional tolerances: Bolt hole center circle error ≤0.5mm Non-destructive testing: 100% radiographic flaw detection and ultrasonic testing [3] Finished products must pass a 150% rated pressure test and issue NACE MR0175 corrosion resistance certification.