Flange dimensions and weights to AWWA C228 Class SB standard. Every size we list is one we manufacture and ship, with custom sizes and modifications available on request.
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Select a flange type to view the AWWA C228 Class SB flange dimensions, including outside diameter, inside diameter, bolt circle, number and size of bolt holes, thickness, and weight.
| API Int. Part Number | Size | O.D. | I.D. | Ø B.H.C. | Ø B.H. | # B.H. | THK | Weight Lbs |
|---|---|---|---|---|---|---|---|---|
| SPF0200-B | 2 | 6.00 | 2.44 | 4.75 | 0.750 | 4 | 0.625 | 3.9 |
| SPF0250-B | 2.5 | 7.00 | 2.94 | 5.50 | 0.750 | 4 | 0.625 | 5.3 |
| SPF0300-B | 3 | 7.50 | 3.57 | 6.00 | 0.750 | 4 | 0.625 | 5.7 |
| SPF0400-B | 4 | 9.00 | 4.57 | 7.50 | 0.750 | 8 | 0.625 | 8.1 |
| SPF0500-B | 5 | 10.00 | 5.66 | 8.50 | 0.875 | 8 | 0.625 | 9.1 |
| SPF0600-B | 6 | 11.00 | 6.72 | 9.50 | 0.875 | 8 | 0.688 | 10.7 |
| SPF0800-B | 8 | 13.50 | 8.72 | 11.75 | 0.875 | 8 | 0.688 | 15.7 |
| SPF1000-B | 10 | 16.00 | 10.88 | 14.25 | 1.000 | 12 | 0.688 | 19.3 |
| SPF1200-B | 12 | 19.00 | 12.88 | 17.00 | 1.000 | 12 | 0.688 | 29.3 |
| SPF1400-B | 14 | 21.00 | 14.19 | 18.75 | 1.125 | 12 | 0.688 | 36.2 |
| SPF1600-B | 16 | 23.50 | 16.19 | 21.25 | 1.125 | 16 | 0.688 | 42.2 |
| SPF1800-B | 18 | 25.00 | 18.19 | 22.75 | 1.250 | 16 | 0.688 | 44.8 |
| SPF2000-B | 20 | 27.50 | 20.19 | 25.00 | 1.250 | 20 | 0.688 | 52.1 |
| SPF2200-B | 22 | 29.50 | 22.19 | 27.25 | 1.375 | 20 | 0.750 | 60.9 |
| SPF2400-B | 24 | 32.00 | 24.19 | 29.50 | 1.375 | 20 | 0.750 | 71.0 |
| SPF2600-B | 26 | 34.25 | 26.19 | 31.75 | 1.375 | 24 | 0.812 | 80.0 |
| SPF2800-B | 28 | 36.50 | 28.19 | 34.00 | 1.375 | 28 | 0.875 | 94.0 |
| SPF3000-B | 30 | 38.75 | 30.19 | 36.00 | 1.375 | 28 | 0.875 | 108.0 |
| SPF3200-B | 32 | 41.75 | 32.19 | 38.50 | 1.625 | 28 | 0.938 | 121.0 |
| SPF3400-B | 34 | 43.75 | 34.19 | 40.50 | 1.625 | 32 | 0.938 | 137.0 |
| SPF3600-B | 36 | 46.00 | 36.19 | 42.75 | 1.625 | 32 | 1.000 | 166.0 |
| SPF3800-B | 38 | 48.75 | 38.19 | 45.25 | 1.625 | 32 | 1.000 | 185.0 |
| SPF4000-B | 40 | 50.75 | 40.19 | 47.25 | 1.625 | 36 | 1.000 | 203.0 |
| SPF4200-B | 42 | 53.00 | 42.19 | 49.50 | 1.625 | 36 | 1.125 | 241.0 |
| SPF4400-B | 44 | 55.25 | 44.19 | 51.75 | 1.625 | 40 | 1.125 | 248.0 |
| SPF4600-B | 46 | 57.25 | 46.19 | 53.75 | 1.625 | 40 | 1.125 | 259.0 |
| SPF4800-B | 48 | 59.50 | 48.19 | 56.00 | 1.625 | 44 | 1.250 | 285.0 |
| SPF5000-B | 50 | 61.75 | 50.19 | 58.25 | 1.875 | 44 | 1.250 | 316.0 |
| SPF5200-B | 52 | 64.00 | 52.19 | 60.50 | 1.875 | 44 | 1.250 | 338.0 |
| SPF5400-B | 54 | 66.25 | 54.19 | 62.75 | 1.875 | 44 | 1.375 | 397.0 |
| SPF6000-B | 60 | 73.00 | 60.19 | 69.25 | 1.875 | 52 | 1.500 | 472.0 |
Each table lists, per nominal size: outside diameter, inside diameter, bolt circle, number and size of bolt holes, thickness, and weight. Dimensions and weights follow the AWWA C228 standard, and every C228 flange uses the ASME/ANSI Class 150 bolt pattern.
We manufacture to your specifications and stock domestic AIS/Buy America and imported materials, with galvanized, epoxy, and additional coatings available. Rubber expansion joints and gaskets are also supplied on request.
AWWA C228 Class SB flange dimensions are defined by nominal pipe size (NPS) and include outside diameter (OD), inside diameter (ID), thickness (THK), bolt circle (BC), number of bolt holes, and hole diameter.
Class SB flanges are typically available in sizes from 2" up to 60" and follow drilling patterns compatible with ASME/ANSI Class 150. Exact dimensions vary by size and must be referenced from AWWA C228 standard tables.
Yes. Being part of AWWA C228, Class SB flanges are typically manufactured from 304/316 stainless steel, making them suitable for humid, chemical, or high-salinity conditions.
AWWA C228 Class SB flanges are rated for 86 psi at atmospheric temperature.
Sometimes, but verify first. For a given size and class the drilling usually lines up, yet C228 is stainless and C207 is carbon steel, each with its own thicknesses and ratings. The right choice depends on the fluid, environment, and pressure, so check those against both standards before swapping.
API International stocks the pipe sizes, pressure classes, and materials you need for your project. Our machine shop can also modify stock products to accommodate any special project requirements. Contact API International’s experienced sales team, and we will help you select the right flange for your application.
