Precision Forged Flanges & Fittings - Built for Global Markets

Technical Data & Specifications

Theoretical flange weights, pipe wall thickness tables, dimensional tolerances, and material grade cross-reference.

ASME B16.5 Flange Theoretical Weights (kg/pc)

Reference weights for standard ASME B16.5 forged steel flanges. Actual weights may vary slightly by manufacturer and material. For precise weights for project costing, please contact us with your specific requirements.

Nominal Size Class 150 WN Class 150 BL Class 150 SO Class 300 WN Class 300 BL Class 300 SO Class 600 WN Class 600 BL
DN15 (1/2")0.50.30.30.60.50.40.70.6
DN20 (3/4")0.70.50.50.90.70.61.00.9
DN25 (1")1.00.70.71.41.10.91.51.3
DN40 (1-1/2")2.01.41.42.92.31.93.22.8
DN50 (2")2.72.01.94.13.32.74.84.2
DN80 (3")5.54.24.08.47.05.810.08.9
DN100 (4")8.06.45.813.010.68.916.013.7
DN150 (6")15.012.611.025.021.317.533.029.0
DN200 (8")23.519.017.040.033.028.056.049.0
DN250 (10")35.027.025.062.050.043.089.077.0
DN300 (12")48.038.035.086.070.061.0125.0108.0
DN350 (14")62.049.044.0110.089.078.0160.0138.0
DN400 (16")80.063.057.0145.0117.0102.0215.0185.0
DN450 (18")100.078.071.0180.0146.0128.0270.0233.0
DN500 (20")125.097.088.0225.0182.0159.0345.0298.0
DN600 (24")180.0138.0126.0335.0271.0237.0530.0458.0

Note:

Weights shown are theoretical reference values for carbon steel / mild steel flanges per ASME B16.5. Actual weights for stainless steel and alloy flanges will differ due to different material densities. For precise weights, please contact our technical team with your exact specifications.

HG/T20592 / EN1092-1 Flange Weights (kg/pc)

Theoretical weights for PN10/PN16/PN25/PN40 European-standard flanges per HG/T20592 (equivalent to EN1092-1). Reference values for PN-series Weld Neck (WN), Blind (BL), and Slip-On (SO) flanges.

Nominal Size PN10 WN PN10 BL PN10 SO PN16 WN PN16 BL PN16 SO PN25 WN PN40 WN
DN150.50.30.30.50.30.30.50.6
DN200.70.50.50.80.50.50.80.9
DN251.00.70.71.00.80.71.11.3
DN402.11.41.42.21.61.52.32.7
DN502.92.12.03.22.32.13.44.0
DN805.84.34.26.54.84.47.08.5
DN1008.56.66.09.57.56.811.013.5
DN15016.013.011.518.015.013.021.027.0
DN20025.020.018.028.023.020.033.044.0
DN25037.029.026.042.033.030.050.068.0
DN30051.040.036.058.046.041.070.097.0
DN40085.066.060.097.077.069.0120.0170.0
DN500132.0102.093.0150.0118.0107.0185.0265.0
DN600190.0145.0132.0220.0170.0154.0275.0400.0

Material Density Correction

Theoretical weights are based on carbon steel (density ~7.85 g/cm3). For stainless steel, multiply by ~1.015. For super duplex (2507), multiply by ~1.01. For nickel alloys, multiply by ~1.08-1.14 depending on alloy. Contact us for precise project weights.

Pipe Wall Thickness / Schedule Reference

Standard pipe schedules per ASME B36.10M/B36.19M, GB/T12459, and JIS B2311/B2312. Schedule numbers indicate wall thickness relative to nominal bore.

NPS (in) OD (mm) SCH 5S (mm) SCH 10S (mm) SCH 20S (mm) SCH 40S (mm) SCH 80S (mm) SCH 160 (mm) XXS (mm)
1/2"21.31.652.11-2.773.734.787.47
3/4"26.71.652.11-2.873.915.567.82
1"33.41.652.772.773.384.556.359.09
1-1/2"48.31.652.773.683.685.087.1410.15
2"60.31.652.773.913.915.548.7411.07
3"88.92.113.054.785.497.6211.1315.24
4"114.32.113.054.786.028.5613.4917.12
6"168.32.773.404.787.1110.9718.2421.95
8"219.12.773.765.168.1812.7023.0122.23
10"273.13.404.195.169.2712.7028.5825.40
12"323.93.964.575.1610.3112.7033.3225.40

Schedule Designation

SCH (Schedule) numbers are standardized wall thickness designations in ASME B36.10M (carbon/alloy steel) and B36.19M (stainless steel). The "S" suffix (e.g., SCH 40S) indicates stainless steel schedule. Higher schedule = thicker wall = higher pressure rating. For flange connections, SCH 10S and SCH 40S are most commonly used.

Dimensional Tolerances

Manufacturing tolerances for forged flanges per ASME B16.5 and EN 1092-1:2007 (Table 22). Our flanges are produced within these tolerance limits.

ASME B16.5 Tolerances

Dimension Tolerance
Bore (Weld Neck, Slip-On)Plus 0.8mm / Minus 0.0mm (1/32")
Outside DiameterPer standard tables (no tolerance stated)
Flange ThicknessPlus 3.2mm / Minus 0.0mm (1/8")
Bolt CirclePlus/Minus 1.6mm (1/16")
Bolt Hole DiameterPlus 0.8mm / Minus 0.0mm
Bolt Circle Concentricity0.8mm max (1/32")
Raised Face HeightPlus/Minus 0.8mm (1/32")
Weld Neck BorePer standard tables
Hub Diameter (at bevel)Plus 0.8mm / Minus 0.0mm

EN 1092-1:2007 Tolerances (Table 22)

Dimension Tolerance
Outside Diameter (D)Per standard tables (approx +/-1%)
Overall Flange Thickness (b)DN15-DN200: +2.0mm / -1.0mm
Overall Flange Thickness (b)DN250-DN600: +3.0mm / -1.0mm
Overall Flange Thickness (b)DN700-DN1000: +4.0mm / -1.0mm
Bore Diameter (B1, B2)H11 per ISO 286 (approx +0.2 to +0.5mm)
Bolt Circle Diameter (k)DN15-DN100: +/-0.8mm
Bolt Circle Diameter (k)DN125-DN600: +/-1.5mm
Bolt Circle Diameter (k)DN700-DN1000: +/-2.0mm
Bolt Hole DiameterPlus 1.5mm / Minus 0.0mm

Custom Tolerances

If your project requires tighter tolerances than standard, please specify in your inquiry. We can produce flanges to custom dimensional specifications and provide detailed inspection reports with measured values.

Need Specific Technical Data?

Contact our technical team for detailed dimensional drawings, 3D models, pressure-temperature ratings, or any technical information needed for your project specification.

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