Anchor Flanges / AF-L
Light Duty Anchor Flange
Economical, lightweight anchor flange for fixing pipes on low and medium pressure lines.
Technical Specifications
Key Features
- Economical design
- Lightweight body
- Fast installation
- Low-to-medium pressure
- Standard ASME sizes
- Surface or embedded mount
Applications
- Water lines
- HVAC systems
- Fire protection lines
- Building service piping
- Low-pressure process
- General purpose piping
Design Features
- Standard reinforcement plate
- Concrete anchor holes
- Protective paint coating
- Weld-neck connection
- Gasket seat
Dimension Table
| Size | Outside Diameter (mm) | Thickness (mm) | Bolt Circle (mm) | No. of Bolts | Anchor Holes | Hole Size (mm) |
|---|---|---|---|---|---|---|
| 2" | 152 | 16 | 120.7 | 4 | 4 | 19 |
| 4" | 229 | 19 | 190.5 | 8 | 4 | 19 |
| 6" | 279 | 22 | 241.3 | 8 | 4 | 22 |
| 8" | 343 | 25 | 298.5 | 8 | 4 | 22 |
| 12" | 483 | 29 | 431.8 | 12 | 6 | 25 |
| 24" | 749 | 40 | 692.2 | 20 | 8 | 35 |
Technical Notes
- 01Minimum concrete strength should be 25 MPa.
- 02Suitable for low and medium pressure lines.
- 03Complies with standard ASME B16.5 flange geometry.
- 04Certified manufacturing drawings provided on request.
What is an anchor flange?
An anchor flange is a heavy forged flange welded into a pipeline and encased in a concrete anchor (thrust) block. It is not a bolted joint: its job is to fix the pipe axially and transfer thrust loads from thermal expansion and internal pressure into the structure. Produced from 2" to 60" to ASME/AWWA practice or fully custom design.
Where and how anchor flanges are used
Anchor flanges are placed wherever the pipeline needs a fixed point: pump and compressor station boundaries, both banks of river and road crossings, steep slopes, aboveground-to-buried transitions and line terminations. The flange is butt-welded into the pipe on both sides and then embedded in a concrete block; expansion forces spread into the concrete through its large outside diameter. Unlike a standard flange it has no gasket face and no bolt holes — it is purely a load-transfer component. Each unit is custom-engineered from the pipe diameter, wall thickness, operating pressure and axial load calculation. Materials: forged carbon steel A105, A694 F42–F70 to match line pipe strength, A350 LF2 for low temperature. Delivered with NDT (UT/MT) and 3.1 certificates.
Frequently Asked Questions
What is the difference between an anchor flange and a standard flange?+
A standard flange is a bolted, demountable joint; an anchor flange has no gasket face or bolt holes — it is a load-transfer component that fixes the pipe into concrete.
What loads does an anchor flange carry?+
Axial thrust loads from thermal expansion/contraction and internal pressure; it takes them from the welded pipe and transfers them into the concrete anchor block.
Where are anchor flanges installed?+
At pump/compressor station boundaries, on both banks of river and road crossings, on steep slopes, at aboveground-to-buried transitions and at line terminations.
Which materials are anchor flanges made from?+
Forged carbon steel A105, A694 F42–F70 to match line-pipe strength, or A350 LF2 for low-temperature service; dimensions are engineered per project and verified with NDT + 3.1 certificates.
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