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1. Introduction: Weld Neck Flanges are flanges that designed to be joined to a piping system by butt welding.
2. Description: Weld neck flange (WN flange) has a neck that can relocated stress of the pipe, so to reduce the pressure that gathered in the flange bottom. It is compatible to the pipelines that works in high or low temperature and bear high pressure.
| Nominal Pipe Size | Outside Diameter (O) | Thickness (T) | Raised Face Diameter (R) | Length Thru Hub (Y) | Hub Diameter (X) | Bore (B) | Approximate Weight (lbs) | Bolt Circle (C) | Number of Holes | Diameter of Holes |
| 1/2 | 4.75 | 0.88 | 1.38 | 2.38 | 1.5 | Specified by purchaser | 5 | 3.25 | 4 | 0.88 |
| 3/4 | 5.13 | 1 | 1.69 | 2.75 | 1.75 | Specified by purchaser | 6 | 3.5 | 4 | 0.88 |
| 1 | 5.88 | 1.13 | 2 | 2.88 | 2.06 | Specified by purchaser | 9 | 4 | 4 | 1 |
| 1 1/4 | 6.25 | 1.13 | 2.5 | 2.88 | 2.5 | Specified by purchaser | 10 | 4.38 | 4 | 1 |
| 1 1/2 | 7 | 1.25 | 2.88 | 3.25 | 2.75 | Specified by purchaser | 13 | 4.88 | 4 | 1.13 |
| 2 | 8.5 | 1.5 | 3.63 | 4 | 4.13 | Specified by purchaser | 25 | 6.5 | 8 | 1 |
| 2 1/2 | 9.63 | 1.63 | 4.13 | 4.06 | 4.88 | Specified by purchaser | 36 | 7.5 | 8 | 1.13 |
| 3 | 9.5 | 1.5 | 5 | 4 | 5 | Specified by purchaser | 31 | 7.5 | 8 | 1 |
| 4 | 11.5 | 1.75 | 6.19 | 4.5 | 6.25 | Specified by purchaser | 53 | 9.25 | 8 | 1.25 |
| 5 | 13.75 | 2 | 7.31 | 5 | 7.5 | Specified by purchaser | 86 | 11 | 8 | 1.38 |
| 6 | 15 | 2.19 | 8.5 | 5.5 | 9.25 | Specified by purchaser | 110 | 12.5 | 12 | 1.25 |
| 8 | 18.5 | 2.5 | 10.63 | 6.38 | 11.75 | Specified by purchaser | 175 | 15.5 | 12 | 1.5 |
| 10 | 21.5 | 2.75 | 12.75 | 7.25 | 14.5 | Specified by purchaser | 260 | 18.5 | 16 | 1.5 |
| 12 | 24 | 3.13 | 15 | 7.88 | 16.5 | Specified by purchaser | 325 | 21 | 20 | 1.5 |
| 14 | 25.25 | 3.38 | 16.25 | 8.38 | 17.75 | Specified by purchaser | 400 | 22 | 20 | 1.63 |
| 16 | 27.75 | 3.5 | 18.5 | 8.5 | 20 | Specified by purchaser | 495 | 24.25 | 20 | 1.75 |
| 18 | 31 | 4 | 21 | 9 | 22.25 | Specified by purchaser | 680 | 27 | 20 | 2 |
| 20 | 33.75 | 4.25 | 23 | 9.75 | 24.5 | Specified by purchaser | 830 | 29.5 | 20 | 2.13 |
| 24 | 41 | 5.5 | 27.25 | 11.5 | 29.5 | Specified by purchaser | 1500 | 35.5 | 20 | 2.63 |
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