The abbreviation SO in piping terms refers to which type of flange?

The abbreviation SO in piping terms refers to which type of flange?

• A. Slip On Flange
• B. Socket Weld Flange
• C. Weld Neck Flange
• D. Blind Flange

Answer: (A)

SO refers to a Slip On flange. In piping, this type slides over the pipe and is then welded both at the inner bore and around the outside to create a leak-tight connection. It’s generally easy to align and install, making it a common, cost-effective choice for low to moderate pressure applications and shorter runs. It’s less robust for high-pressure, high‑temperature service compared with welded neck flanges, but it’s simpler and quicker to manufacture and assemble. For comparison, a Socket Weld flange is welded to the pipe at the socket joint on the flange’s bore, typically used for smaller-diameter lines. A Weld Neck flange has a long tapered neck that provides strength and stress relief for high-pressure service. A Blind flange has no bore and is used to seal a line.

SO refers to a Slip On flange. In piping, this type slides over the pipe and is then welded both at the inner bore and around the outside to create a leak-tight connection. It’s generally easy to align and install, making it a common, cost-effective choice for low to moderate pressure applications and shorter runs. It’s less robust for high-pressure, high‑temperature service compared with welded neck flanges, but it’s simpler and quicker to manufacture and assemble.

For comparison, a Socket Weld flange is welded to the pipe at the socket joint on the flange’s bore, typically used for smaller-diameter lines. A Weld Neck flange has a long tapered neck that provides strength and stress relief for high-pressure service. A Blind flange has no bore and is used to seal a line.