Nickel Alloy Flat Face Flanges

Flat face flanges (FF flanges) are flange types with a complete flat sealing surface. Featuring large sealing surface area, easy gasket installation, and suitability for cast iron equipment and low-pressure applications, they are widely used in water treatment, low-pressure chemical piping, fire protection systems, HVAC, and general industrial connections. The nickel alloy flat face flanges supplied by us are manufactured from high-quality nickel-based alloy forgings or plates through multiple precision processes including forging/cutting, solution heat treatment, machining, drilling, and pickling/passivation. Featuring flat sealing surface, high machining precision, excellent corrosion resistance, and easy installation, they are specifically designed for low-pressure, non-critical applications or connections with cast iron equipment.

Application Notes:

1. Flat face flanges are typically used for low-pressure applications up to Class 150
2. Particularly suitable for connections with cast iron valves, pumps, and equipment
3. Can use full face gaskets (non-metallic gaskets, rubber gaskets, etc.)

Supply Range

Flange Type: Slip-On, Plate Flange, Hubbed Slip-On, Blind

Nominal Diameter (DN/NPS): DN15 – DN600 (1/2 inch – 24 inches); Larger diameters up to DN3000 negotiable

Pressure Class: Class 150 (ASME); PN 6, PN 10, PN 16, PN 25 (EN)

Machining Precision: Sealing surface roughness Ra 3.2μm – 6.3μm (higher available upon request)

Surface Condition: Machined, Pickled optional

Marking: Steel stamp marking on flange outer edge, conforming to MSS SP-25 or customer requirements

Dimensional Inspection

1. Overall Dimensions: Measuring all critical dimensions using calipers, micrometers, tape measures
2. Sealing Surface Flatness: Measuring using surface plates and feeler gauges
3. Bolt Holes: Inspecting hole diameter, bolt circle, hole position
4. Bore Diameter: Measuring bore size ensuring pipe matching

Appearance Inspection

1. Sealing Surface: Inspecting for scratches, pits, rust
2. Surface Quality: Visual inspection, no cracks, folds, laps, or other defects

Non-Destructive Testing

1. Penetrant Testing (PT): 100% inspection of sealing surface and critical areas
2. Ultrasonic Testing (UT): Inspection for critical service flanges

Stock Availability

We maintain inventory of common specifications for mainstream grades such as Inconel 600/625, Monel 400, and Hastelloy C-276 flat face flanges.