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Alloy 20 Flanges

Alloy 20 Flanges Specifications

Material Grades

  • Alloy 20
  • UNS N08020
  • ASTM B462
  • ASME SB462
  • Carpenter 20
  • 20Cb-3
  • Werkstoff No. 2.4660
  • NiCr20CuMo

Flange Types

  • Weld Neck Flanges
  • Slip On Flanges
  • Blind Flanges
  • Socket Weld Flanges
  • Threaded Flanges
  • Lap Joint Flanges
  • Long Weld Neck Flanges
  • Orifice Flanges
  • Ring Type Joint Flanges
  • Reducing Flanges

Flange Testing

  • Positive Material Identification (PMI)
  • Ultrasonic Testing
  • Liquid Penetrant Testing
  • Hydrostatic Testing
  • Hardness Testing
  • Tensile Testing
  • Intergranular Corrosion Testing
  • Dimensional Inspection

Value Added Services

  • Solution Annealing
  • Stabilizing Heat Treatment
  • Pickling & Cleaning
  • Machining
  • Shot Blasting
  • Custom Finishing
  • Custom Marking
  • Export Packing

Manufacturing Standards

  • ASTM B462
  • ASME SB462
  • ASME B16.5
  • ASME B16.47 Series A & B
  • ASME B16.48
  • EN 1092-1
  • DIN Standards
  • BS 4504
  • Custom Drawings

Flanges Sizes

  • Size: 1/2" – 24" per ASME B16.5
  • Large Diameter: 26" – 60" per ASME B16.47
  • Pressure Class: 150 – 2500 LBS
  • Pressure Rating: PN6 – PN64
  • Faces: RF, FF & RTJ

Flange Dimensions Chart

NPS Bolt Circle (mm) Flange O.D. (mm) Thickness (mm) Bolt Hole Ø (mm) No. Of Bolts
½″ 60.5 88.9 11.2 15.7 4
¾″ 69.9 98.6 12.7 15.7 4
1″ 79.2 108 14.2 15.7 4
1¼″ 88.9 117.3 15.7 15.7 4
1½″ 98.6 127 17.5 15.7 4
2″ 120.7 152.4 19.1 19.1 4
2½″ 139.7 177.8 22.4 19.1 4
3″ 152.4 190.5 23.9 19.1 4
4″ 190.5 228.6 23.9 19.1 8
5″ 215.9 254 23.9 22.4 8
6″ 241.3 279.4 25.4 22.4 8
8″ 298.5 342.9 28.4 22.4 8
10″ 362 406.4 30.2 25.4 12
12″ 431.8 482.6 31.8 25.4 12
14″ 476.3 533.4 35.1 28.4 12
16″ 539.8 596.9 36.6 28.4 16
18″ 577.9 635 39.6 31.8 16
20″ 635 698.5 42.9 31.8 20
24″ 749.3 812.8 47.8 35.1 20

Weight Chart

NPS Class Weight / Pc (kg)
½″1501.0
¾″1501.5
1″1501.9
1¼″1502.5
1½″1503.0
2″1504.5
2½″1506.5
3″1508.0
4″15011.5
5″15014.5
6″15018.5
8″15029.0
10″15042.0
12″15060.0
14″15082.0
16″150105.0
18″150128.0
20″150155.0
24″150215.0

Chemical Composition

Nickel (Ni)
32–38%
Chromium (Cr)
19–21%
Iron (Fe)
29.85% min
Molybdenum (Mo)
2–3%
Copper (Cu)
3–4%
Manganese (Mn)
2.00% max
Silicon (Si)
1.00% max
Carbon (C)
0.07% max
Phosphorus (P)
0.045% max
Sulfur (S)
0.035% max
Physical Density: 8.1 g/cm³
Density: 8100 kg/m³
Melting Point: 1443°C
Melting Point: 2430°F

Mechanical Performance

551
MPa (80,000 psi)
Tensile Strength
241
MPa (35,000 psi)
Yield Strength
30%
minimum
Elongation
200
GPa
Modulus of Elasticity
217
HBW max
Hardness
20
Cb-3
Stabilized Alloy


MANUFACTURING

Forging Process

Each flange follows a rigorous 8-step forging and quality-control process to ensure conformance with ASTM A182 and ASME standards.

1

Material Selection

Prime 304 stainless steel billet sourced and certified.

2

Billet Preparation

Heat to 1100°C – 1250°C for optimal forgeability.

3

Forging

Shape billet into flange geometry under controlled pressure.

4

Heat Treatment

Solution anneal at 1040°C – 1120°C, then quench.

5

Machining & Finishing

CNC machining, drilling, and surface finishing.

6

Testing & Inspection

Tensile, hardness, PMI, visual and impact tests performed.