ASME B16.5 Class 900 pressure-rated SO flanges (slip-on flanges) combine the load-bearing capacity for high-pressure conditions with the ease of installation of a slip-on structure, playing a crucial role in medium- and high-pressure fluid transportation scenarios. HT PIPE supply all different types and scales of flanges. Please feel free to contact us for further product information and pricing.
What is ASME B16.5 SO Flange?
SO flanges (slip-on flanges) are characterized by a short neck on the flange plate. Pipes can be directly inserted into the flange's inner bore, and the connection is completed through a fillet weld between the flange and the outer ring of the pipe. This eliminates the need for complex beveling of the pipe ends, and welding is only required at the joint between the flange and the outer ring of the pipe. This reduces construction difficulty, increases efficiency, and relatively lowers the technical requirements for welders.
Key Advantages of SO Flange
Strong High-Pressure Adaptability: The Class 900 design allows it to withstand pressures up to 15.3 MPa at a reference temperature, making it suitable for medium- and high-pressure fluid transportation scenarios. It meets the stringent operating conditions of industries such as petrochemicals and power generation, overcoming the limitation of lower-grade SO flanges in high-pressure applications.
Easy and efficient installation: The flat-face welding connection eliminates the need for complex beveling, welding can be performed immediately after pipe insertion. The construction process is simple and quick, effectively reducing on-site installation costs. Furthermore, the alignment requirements between the flange and the pipe are relatively low, facilitating on-site adjustments for installation deviations.
High cost-effectiveness: Compared to WN flanges (welding flanges) of the same pressure rating, SO flanges have a simpler forging process, use less material, and have lower manufacturing costs. Installation time is also shorter, enabling the reduction of overall project costs while ensuring high-pressure load-bearing capacity.
Strong interchangeability: Strictly adhering to the ASME B16.5 standard dimensional specifications, Class 900 SO flanges from different manufacturers share identical key parameters such as flange outer diameter, bolt hole distribution, and sealing surface dimensions, facilitating future maintenance and replacement.
SO Flange Sealing Surface Types
Raised Face (RF): The most widely used sealing surface type. It features a raised surface, compatible with various gasket types such as asbestos gaskets, rubber gaskets, and metal-coated gaskets. It offers strong installation compatibility, reliable sealing performance, and is suitable for most medium- and high-pressure, non-corrosive media applications.
Flat Face (FF): The sealing surface is flat and without raised surfaces. It is mainly used in applications requiring frequent disassembly and cleaning, or for use with special gaskets (such as PTFE gaskets). However, its sealing performance is slightly lower than that of the raised face type. It is suitable for applications with relatively stable media pressure and no drastic fluctuations.
ASME B16.5 SO Flange Dimension
