Backing Rings

Effast backing rings are used in conjunction with stub flanges to form strong, secure flanged joints within thermoplastic piping systems. Manufactured from galvanised steel for strength and corrosion resistance, these rings provide the clamping force needed to compress gaskets and ensure a leak-tight seal when bolted to valves, flanges, or pipework. Available in a variety of drilling standards, Effast backing rings are suitable for a wide range of industrial and commercial fluid systems.

• Material: Galvanised steel
• Application: Used with stub flanges and gaskets in PVCu, ABS, and PP systems
• Drilling Standards Available:
  – BS EN 1092-1 PN10/16
  – BS 10:1962 Tables D and E
  – ASA/ANSI 150
• Compatible With: Effast thermoplastic flange fittings and pipe systems
• Corrosion Resistance: Galvanised coating protects against environmental wear and moisture
• Function: Distributes clamping force evenly across gasketed flanged joints

• Preparation: Ensure the mating flange surfaces are clean, flat, and free of debris or damage. Confirm that the gasket material is compatible with the system fluid and temperature.
• Position Components: Solvent weld the stub flange to the thermoplastic pipe. Once cured, place the gasket between the stub flange and the mating flange. Align the backing ring over the stub flange and gasket.
• Bolt Assembly: Insert the bolts through the aligned holes of the backing ring and mating flange. Use washers and nuts as specified. Ensure even spacing and use a star pattern when tightening.
• Tightening Sequence: Tighten bolts gradually in a criss-cross/star pattern to ensure even compression of the gasket. Avoid overtightening, especially with plastic components, to prevent damage.
• Final Check: Once all bolts are torqued to the manufacturer’s recommendation, visually inspect the joint. Allow the system to stabilise before pressure testing.

Key Considerations:

• Always match drilling standards between the backing ring and the mating flange (e.g., PN10/16, ASA 150).
• Do not use backing rings with incompatible flange face types.
• In systems subject to vibration or thermal expansion, check bolt torque periodically.