Plate Flange (PL)

Overview: Plate Flange (PL)

A plate flange (PL) is a plain flat ring without a hub. The pipe is inserted into the flange bore and fillet welded on both sides. Its simple structure makes it a low cost and easy-to-fabricate ring for general utility piping.

Choosing a Plate Flange vs. Avoiding One

Whether a plate flange is the right fit comes down to pressure, temperature and the nature of the conveyed fluid. The points below set its strengths against its limits.

• Strength — Simple structure, low cost and easy fabrication, which keeps both material and machining effort low.
• Strength — Well suited to low pressure & low temperature, non-critical general utilities.
• Weakness — No stress relief hub, so the flange is weaker under bending and cyclic load.
• Weakness — Not for high pressure, flammable or toxic fluid.

Sealing Faces and Applicable Standards

Available sealing faces for the plate flange are RF and FF. The type is covered by the following standards.

Application Conclusion: Where the PL Fits

Select a plate flange for low pressure & low temperature, non-critical general utilities: water pipeline, ventilation, low-pressure compressed air and general civil piping. Do not select it for high pressure, flammable or toxic fluid.