Bi‑Metallic Flanges supplied by Anchor Building Materials Trading LLC are engineered for water, gas, and sanitary piping systems using copper tubes manufactured to BS EN 1057. These flanges consist of a bronze (gunmetal) or copper alloy brazing collar permanently fitted into a machined steel backing flange, providing a strong, corrosion‑resistant and pressure‑rated connection.

Designed and manufactured to BS EN 1092‑3:2003 (BS 4504 Part 3.3) and BS 4504 Part 2, these flanges are suitable for brazing or soldering to copper tube ends, ensuring a secure and leak‑free joint. They are available in PN16 and PN25 pressure ratings, with performance verified across a wide temperature range from –10°C to 260°C, as specified in the catalogue.

Bi‑Metallic Flanges are widely used in potable water systems, chilled water lines, gas distribution, HVAC copper piping, industrial copper networks, and sanitary installations. Their composite construction prevents galvanic corrosion, ensures long‑term durability, and provides compatibility with standard flange drilling patterns.

⭐ Features

• Copper alloy brazing collar suitable for BS EN 1057 copper tubes
• Steel backing flange with machined finish and epoxy coating
• Manufactured to BS EN 1092‑3:2003 & BS 4504 Part 2
• Available in PN16 and PN25 pressure ratings
• Suitable for brazing or soft‑soldering (up to 67 mm OD)
• High temperature resistance up to 260°C (depending on PN rating)
• Available in solid bronze or composite (bi‑metallic) construction
• Accurate machining tolerances per BS EN 1092‑3 Table 10
• Bolt holes, PCD, and flange OD as per BS 4504 drilling tables

⭐ Material of Construction 

Non‑Ferrous (Copper Alloy) Components

• Forgings: CA104 (BS 2872)
• Castings: LG2 (BS 1400)
• EN 1982: CuSn5Pb5Zn5‑C (CC491K)

Ferrous (Steel) Backing Flange Components

• Plates:
  • BS 1501 Grade 23A
  • BS 4360 Grade 43A
  • EN 10028‑2 P265GH / P295GH
• Forgings:
  • BS 1503‑221‑430
  • BS 1503‑164‑490
  • EN 10222‑2 P245GH

Finishing

• Steel backing flange supplied with green/blue epoxy coating, cured at 120°C
• Copper alloy collars supplied fully machined

⭐ Sizes Available

Tube OD to Suit BS EN 1057 Copper Tube

• DN10 to DN250
• Tube OD range: 15 mm to 267 mm

Available Types

• PN16 Bi‑Metallic Brazing Flanges (BS 4504 Part 2 Table 16/23)
• PN16 Bi‑Metallic Blanking Flanges
• PN16 Type 07 (BS EN 1092‑3)
• PN25 Type 02 (BS EN 1092‑3)
• PN25 Type 05C Blanking Flanges
• PN25 Type 14 Solid Bronze Flanges

Bolt Hole Patterns

• 4‑hole, 8‑hole, and 12‑hole patterns depending on DN
• Bolt sizes: M12, M16, M20, M24

⭐ Applications

• Potable water distribution systems
• Gas supply networks
• Sanitary and plumbing installations
• HVAC copper piping systems
• Industrial copper tube networks
• Brazed or soldered copper tube connections
• Flanged connections requiring copper‑to‑steel transition
• Pressure‑rated copper tube systems (PN16 / PN25)