ANSI / ASME B16.5 Class 300 Weld Neck Flange Dimensions
B16.5 300# Weld Neck Flange is a type of weld neck flange that conforms to the ASME B16.5 standard
ANSI / ASME B16.5 Class 300 Weld Neck Flange
Class 300 Weld Neck Flange Dimensions in Inch/lbs
Class 300 Weld Neck Flange Dimensions in mm/kg
Class 300 Weld Neck Flange Dimensions in Inch/lbs
| Nominal Pipe Size | Outside Diameter (Q) | Thickness (T) | Raised Face Diameter (R) | Length Thru Hub (Y) | Point of Weld (A) | Hub Diameter (X) | Bore (B) | Approximate Weight (lbs) | Bolt Circle (C) | Number of Holes | Diameter of Holes |
| 1/2 | 3.75 | 0.56 | 1.38 | 2.06 | 0.84 | 1.50 | 0.62 | 2 | 2.63 | 4 | 0.63 |
| 3/4 | 4.63 | 0.63 | 1.69 | 2.25 | 1.05 | 1.88 | 0.82 | 3 | 3.25 | 4 | 0.75 |
| 1 | 4.88 | 0.69 | 2.00 | 2.44 | 1.32 | 2.13 | 1.05 | 4 | 3.50 | 4 | 0.75 |
| 1 1/4 | 5.25 | 0.75 | 2.50 | 2.56 | 1.66 | 2.50 | 1.38 | 5 | 3.88 | 4 | 0.75 |
| 1 1/2 | 6.13 | 0.81 | 2.88 | 2.69 | 1.90 | 2.75 | 1.61 | 7 | 4.50 | 4 | 0.88 |
| 2 | 6.50 | 0.88 | 3.63 | 2.75 | 2.38 | 3.31 | 2.07 | 9 | 5.00 | 8 | 0.75 |
| 2 1/2 | 7.50 | 1.00 | 4.13 | 3.00 | 2.88 | 3.94 | 2.47 | 12 | 5.88 | 8 | 0.88 |
| 3 | 8.25 | 1.13 | 5.00 | 3.13 | 3.50 | 4.63 | 3.07 | 15 | 6.63 | 8 | 0.88 |
| 3 1/2 | 9.00 | 1.19 | 5.50 | 3.19 | 4.00 | 5.25 | 3.55 | 18 | 7.25 | 8 | 0.88 |
| 4 | 10.00 | 1.25 | 6.19 | 3.38 | 4.50 | 5.75 | 4.03 | 25 | 7.88 | 8 | 0.88 |
| 5 | 11.00 | 1.38 | 7.31 | 3.88 | 5.56 | 7.00 | 5.05 | 32 | 9.25 | 8 | 0.88 |
| 6 | 12.50 | 1.44 | 8.50 | 3.88 | 6.63 | 8.13 | 6.07 | 42 | 10.63 | 12 | 0.88 |
| 8 | 15.00 | 1.63 | 10.63 | 4.38 | 8.63 | 10.25 | 7.98 | 67 | 13.00 | 12 | 1.00 |
| 10 | 17.50 | 1.88 | 12.75 | 4.63 | 10.75 | 12.63 | 10.02 | 91 | 15.25 | 16 | 1.13 |
| 12 | 20.50 | 2.00 | 15.00 | 5.13 | 12.75 | 14.75 | 12.00 | 140 | 17.75 | 16 | 1.25 |
| 14 | 23.00 | 2.13 | 16.25 | 5.63 | 14.00 | 16.75 | 13.25 | 180 | 20.25 | 20 | 1.25 |
| 16 | 25.50 | 2.25 | 18.50 | 5.75 | 16.00 | 19.00 | 15.25 | 250 | 22.50 | 20 | 1.38 |
| 18 | 28.00 | 2.38 | 21.00 | 6.25 | 18.00 | 21.00 | 17.25 | 320 | 24.75 | 24 | 1.38 |
| 20 | 30.50 | 2.50 | 23.00 | 6.38 | 20.00 | 23.13 | 19.25 | 400 | 27.00 | 24 | 1.38 |
| 22 | 33.00 | 2.63 | 25.25 | 6.50 | 22.00 | 25.25 | 21.25 | 465 | 29.25 | 24 | 1.63 |
| 24 | 36.00 | 2.75 | 27.25 | 6.63 | 24.00 | 27.63 | 23.25 | 580 | 32.00 | 24 | 1.63 |
Class 300 Weld Neck Flange Dimensions in mm/kg
| Nominal Pipe Size | Outside Diameter (Q) | Thickness (T) | Raised Face Diameter (R) | Length Thru Hub (Y) | Point of Weld (A) | Hub Diameter (X) | Bore (B) | Approximate Weight (kg) | Bolt Circle (C) | Number of Holes | Diameter of Holes |
| 1/2 | 95.3 | 14.2 | 35.1 | 52.3 | 21.3 | 38.1 | 15.7 | 0.9 | 66.8 | 4 | 16.0 |
| 3/4 | 117.6 | 16.0 | 42.9 | 57.2 | 26.7 | 47.8 | 20.8 | 1.4 | 82.6 | 4 | 19.1 |
| 1 | 124.0 | 17.5 | 50.8 | 62.0 | 33.5 | 54.1 | 26.7 | 1.8 | 88.9 | 4 | 19.1 |
| 1 1/4 | 133.4 | 19.1 | 63.5 | 65.0 | 42.2 | 63.5 | 35.1 | 2.3 | 98.6 | 4 | 19.1 |
| 1 1/2 | 155.7 | 20.6 | 73.2 | 68.3 | 48.3 | 69.9 | 40.9 | 3.2 | 114.3 | 4 | 22.4 |
| 2 | 165.1 | 22.4 | 92.2 | 69.9 | 60.5 | 84.1 | 52.6 | 4.1 | 127.0 | 8 | 19.1 |
| 2 1/2 | 190.5 | 25.4 | 104.9 | 76.2 | 73.2 | 100.1 | 62.7 | 5.4 | 149.4 | 8 | 22.4 |
| 3 | 209.6 | 28.7 | 127.0 | 79.5 | 88.9 | 117.6 | 78.0 | 6.8 | 168.4 | 8 | 22.4 |
| 3 1/2 | 228.6 | 30.2 | 139.7 | 81.0 | 101.6 | 133.4 | 90.2 | 8.2 | 184.2 | 8 | 22.4 |
| 4 | 254.0 | 31.8 | 157.2 | 85.9 | 114.3 | 146.1 | 102.4 | 11.3 | 200.2 | 8 | 22.4 |
| 5 | 279.4 | 35.1 | 185.7 | 98.6 | 141.2 | 177.8 | 128.3 | 14.5 | 235.0 | 8 | 22.4 |
| 6 | 317.5 | 36.6 | 215.9 | 98.6 | 168.4 | 206.5 | 154.2 | 19.1 | 270.0 | 12 | 22.4 |
| 8 | 381.0 | 41.4 | 270.0 | 111.3 | 219.2 | 260.4 | 202.7 | 30.4 | 330.2 | 12 | 25.4 |
| 10 | 444.5 | 47.8 | 323.9 | 117.6 | 273.1 | 320.8 | 254.5 | 41.3 | 387.4 | 16 | 28.7 |
| 12 | 520.7 | 50.8 | 381.0 | 130.3 | 323.9 | 374.7 | 304.8 | 63.5 | 450.9 | 16 | 31.8 |
| 14 | 584.2 | 54.1 | 412.8 | 143.0 | 355.6 | 425.5 | 336.6 | 81.6 | 514.4 | 20 | 31.8 |
| 16 | 647.7 | 57.2 | 469.9 | 146.1 | 406.4 | 482.6 | 387.4 | 113.4 | 571.5 | 20 | 35.1 |
| 18 | 711.2 | 60.5 | 533.4 | 158.8 | 457.2 | 533.4 | 438.2 | 145.1 | 628.7 | 24 | 35.1 |
| 20 | 774.7 | 63.5 | 584.2 | 162.1 | 508.0 | 587.5 | 489.0 | 181.4 | 685.8 | 24 | 35.1 |
| 22 | 838.2 | 66.8 | 641.4 | 165.1 | 558.8 | 641.4 | 539.8 | 210.9 | 743.0 | 24 | 41.4 |
| 24 | 914.4 | 69.9 | 692.2 | 168.4 | 609.6 | 701.8 | 590.6 | 263.1 | 812.8 | 24 | 41.4 |
Features of ASME B16.5 300# Weld Neck Flange
- Standard: Complies with ANSI/ASME B16.5 standards, suitable for piping and fittings.
- Pressure Rating: Class 300, designed for 300-pound pressure rating.
- Type: Weld Neck Flange, featuring a long neck for easy welding.
- Material: Common materials include carbon steel, stainless steel, and alloy steel.
- Size: Covers pipe sizes from 1/2 inch to 24 inches.
- Facing: Common facing types include Flat Face (FF), Raised Face (RF), and Ring-Type Joint (RTJ).
- Bolt Holes: Standardized number and diameter of bolt holes to ensure compatibility with other flanges.
Applications of ASME B16.5 300# Weld Neck Flange
- Oil and Gas: Used in high-pressure and high-temperature piping systems.
- Chemical Industry: Suitable for transporting corrosive media.
- Power Generation: Used in high-pressure steam and cooling water systems in power plants.
- Shipbuilding: Utilized in ship piping systems.
- Water Treatment: Applied in high-pressure water treatment and transportation systems.
B16.5 300# Weld Neck Flange is a high-performance flange suitable for various industrial applications. Proper selection, installation, and maintenance are key to ensuring its long-term stable operation. For more technical support, please contact SSM.
FAQ
- Class 300 indicates that the flange has a maximum allowable working pressure of 300 pounds per square inch (psi) at a specific temperature.
- A Weld Neck Flange has a long neck for welding, providing better strength and sealing performance, making it suitable for high-pressure and high-temperature environments.
- The choice of facing type depends on application requirements. Raised Face (RF) is suitable for most applications, Flat Face (FF) for low-pressure applications, and Ring-Type Joint (RTJ) for high-pressure applications.
- Material selection affects the flange’s corrosion resistance, strength, and temperature range. Choose the appropriate material based on the chemical properties of the medium and operating conditions.
- During installation, ensure the flange is aligned with the pipe, follow standard welding procedures to ensure weld quality, and conduct pressure testing after installation to ensure sealing performance.
- Regularly inspect the tightness of bolts, the condition of the facing, and signs of corrosion. Replace damaged components promptly to ensure the safe operation of the system.
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