1/2 inch ASME B16.5 Class 900 Flange Dimensions
1/2 inch (DN 15) to ASME B16.5: OD 120 mm; thickness 22.3 mm; raised face 34.9 mm; hub 38 mm; pipe OD 21.3 mm.
Key to dimensions
- O
- Outside diameter of flange
- tf
- Minimum flange thickness (also the blind flange thickness), excluding the raised face
- R
- Diameter of raised face
- X
- Hub diameter at base
- A
- Hub diameter at the welding end of a weld neck flange (pipe outside diameter)
- Y
- Length through hub — given separately for weld neck, slip-on / threaded / socket weld and lap joint flanges
- W
- Bolt circle diameter
- Holes
- Number and diameter of bolt holes
- Bolt
- Nominal bolt diameter in inches
1/2 inch ASME B16.5 Class 900 Flange Dimensions — all dimensions
Class 900 flange dimensions (mm)
| Dimension | Value | Equivalent |
|---|---|---|
| DN | 15 | |
| Outside dia — O | 120 mm | 4.72 in |
| Min thickness — tf | 22.3 mm | 0.878 in |
| Raised face dia — R | 34.9 mm | 1.37 in |
| Hub dia — X | 38 mm | 1.50 in |
| Hub at weld — A | 21.3 mm | 0.839 in |
| Weld neck — Y | 60 mm | 2.36 in |
| Slip-on / Thr / SW — Y | 32 mm | 1.26 in |
| Lap joint — Y | 32 mm | 1.26 in |
| Bolt circle — W | 82.6 mm | 3.25 in |
| Number of holes | 4 | |
| Hole dia | 22.2 mm | 0.874 in |
| Bolt size | ¾" |
Class 900 bolting and approximate weights
| Dimension | Value | Equivalent |
|---|---|---|
| Number of studs | 4 | |
| Stud dia | ¾" | |
| Stud length — Raised face | 110 mm | 4.33 in |
| Stud length — Ring joint | 110 mm | 4.33 in |
| Slip-on — kg, approx. | 1.8 kg | 4.0 lb |
| Blind — kg, approx. | 1.8 kg | 4.0 lb |
Values are nominal, from ASME B16.5 Class 900 Flange Dimensions. Verify critical dimensions against the current edition of the standard before design, purchase or fabrication.
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1/2 inch ASME B16.5 Class 900 Flange Dimensions: common questions
What are the 1/2 inch ASME B16.5 Class 900 Flange Dimensions?
1/2 inch (DN 15) to ASME B16.5: OD 120 mm; thickness 22.3 mm; raised face 34.9 mm; hub 38 mm; pipe OD 21.3 mm.
Does Teshi Group manufacture 1/2 inch flanges?
Yes. Teshi Group is an OEM manufacturer in India of flanges to ASME B16.5, in carbon, alloy, stainless, duplex, super duplex, nickel alloys, titanium and Cu-Ni, with EN 10204 3.1 certificates.
Can I download the 1/2 inch dimensions as a PDF?
Yes. Use “Download PDF for this size” on this page to get a single-size, print-ready PDF with the drawing and every tabulated dimension, or download the full ASME B16.5 Class 900 Flange Dimensions chart.
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