Understanding ASTM A182 F347 Material
ASTM A182 F347 Material is an austenitic stainless steel stabilized with Columbium (Niobium). In 304 stainless steel, exposure to temperatures between 800°F and 1500°F can cause chromium carbides to precipitate at grain boundaries. This phenomenon, known as sensitization, leads to intergranular corrosion, especially after welding.
F347 solves this problem. The addition of Columbium acts as a stabilizer. It prefers to combine with carbon before chromium does, preserving the corrosion resistance of the steel even after exposure to high heat.
It prevents chromium carbide precipitation during welding or when the material is exposed to temperatures between 425°C and 815°C. By "stabilizing" the steel, Niobium ensures the material maintains its corrosion resistance in the heat-affected zones of welds, effectively eliminating the risk of intergranular corrosion.
ASME B16.5 Slip On Flanges Product Specifications
We manufacture our Stainless Steel ASTM A182 347 Slip On Flanges to the latest edition of ASME B16.5. This ensures full compatibility with standard piping systems worldwide. Key specifications include:
Size range: NPS ½" to 24" (larger diameters available on special order)
Pressure classes: 150, 300, 600, 900, 1500, and 2500
Facing types: Raised Face (RF) as standard; Flat Face (FF) and Ring-Type Joint (RTJ) available
Bore: Standard or custom-matched to your pipe schedule
Manufacturing standard: ASTM A182 / ASME B16.5 / MSS SP-6 / MSS SP-25
The slip-on design slips easily into the flange bore, and two fillet welds (inside and outside) secure the joint. This configuration offers easier alignment during installation, lower cost than weld-neck flanges, and sufficient strength for moderate-pressure and moderate-temperature service.
For quick reference, here are typical dimensions for Class 150 Raised Face Slip On Flanges (in inches):
NPS 2": Outside diameter 6.00, Thickness 0.75, Bolt circle 4.75, 4 bolts of 5/8"
NPS 4": Outside diameter 9.00, Thickness 0.94, Bolt circle 7.50, 8 bolts of 5/8"
NPS 6": Outside diameter 11.00, Thickness 1.00, Bolt circle 9.50, 8 bolts of 3/4"
NPS 8": Outside diameter 13.50, Thickness 1.12, Bolt circle 11.75, 8 bolts of 3/4"
We maintain extremely tight tolerances on hub height, bore diameter, facing flatness, and bolt-hole alignment. Every flange is 100% dimensionally inspected before shipment.
Technical Specifications and Dimensions
Our Slip On Flanges are manufactured to meet the dimensional standards of ASME B16.5 and ASME B16.47. These standards ensure interchangeability and safety across global piping systems. We produce these flanges in a wide range of pressure classes to suit various operational needs.
Pressure Classes: We supply Class 150, 300, 600, 900, 1500, and 2500.
Sizes: Nominal Pipe Sizes (NPS) range from 1/2 inch to 48 inches.
Facing: Standard options include Raised Face (RF), Flat Face (FF), and Ring Type Joint (RTJ).
The Slip On design allows the pipe to slide into the flange before welding. This offers a lower initial cost compared to Weld Neck flanges while providing sufficient strength for many applications. And, our machining centers ensure that the bore diameter matches the pipe outer diameter within tight tolerances, facilitating easy assembly and proper weld penetration.
Physical and Mechanical Properties
Strength under stress is what defines our forged flanges. ASTM A182 347 provides excellent creep and stress rupture properties, which are superior to those of Grade 304 or 304L.
Mechanical Requirements:
Tensile Strength: 515 MPa (min)
Yield Strength (0.2% Offset): 205 MPa (min)
Elongation: 30% (min)
Hardness: 187 Brinell (max)
These properties ensure that our flanges can withstand the thermal expansion and contraction cycles common in steam services and high-temperature chemical reactors without cracking or deforming.
Our Production Process
As a direct manufacturer, we maintain strict control over the production lifecycle. This ensures authenticity and quality that trading companies cannot match.
Raw Material Selection: We begin with certified round bars or forged billets. Positive Material Identification (PMI) is conducted upon arrival to verify the alloy grade.
Forging: The flanges are die-forged under high pressure. This process refines the grain structure of the metal, eliminating voids and improving mechanical strength compared to simple cutting from plate.
Machining: CNC lathes and drilling machines shape the flange to ASME dimensions. We pay close attention to the hub thickness and face flatness.
Heat Treatment: This is the most critical step for F347. The flanges undergo solution annealing at temperatures between 1925°F and 2010°F, followed by rapid quenching. This dissolves any carbides formed during forging and restores corrosion resistance.
Final Finishing: Surfaces are cleaned and passivated to remove free iron and enhance the natural oxide layer.
Quality Assurance and Inspection
Quality is not an afterthought; it is integrated into every step. We understand that our customers require documentation to validate their own safety protocols. Every shipment is accompanied by a Mill Test Report (MTR) EN 10204 3.1, which traces the material back to the original melt.
Our inspection procedures include:
Dimensional Inspection: Verifying all critical measurements against ASME B16.5.
Visual Testing (VT): Checking for surface defects, cracks, or seams.
Liquid Penetrant Testing (PT): Detecting surface-breaking discontinuities.
Ultrasonic Testing (UT): Ensuring internal soundness of the forging.
Hydrostatic Testing: Upon request, we can perform pressure testing to validate leak tightness.
PMI Testing: Final verification of the chemical grade before packing.
We welcome third-party inspections from agencies such as SGS, BV, or TUV. Our factory is open for audits, demonstrating our confidence in our production capabilities.
Why Choose Jinie as Your Supplier?
When you buy from us, you deal directly with the factory. There are no middlemen, no hidden markups, and no surprises. You receive:
Competitive factory-direct pricing
Fast production lead times (often 2–4 weeks for standard sizes)
Technical support from metallurgists who truly understand the material
Flexible minimum order quantities
Reliable global shipping with professional export packaging
Many of our customers started with a trial order of just a few pieces. They now place regular bulk orders because they know our quality is consistent and our promises are kept.
If you are searching for a trusted Stainless Steel ASTM A182 347 Slip On Flange supplier, I invite you to contact our team today. Whether you need standard Class 150 flanges, custom bores, or technical drawings for your next project, we are ready to help.
