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ASME B16.5 Class 300 pipe flanges, NPS ½ to 24: dimensions, bolt circle, slip-on and blind
What are the dimensions of an ASME B16.5 Class 300 flange (OD, thickness, raised face, bolt circle, bolt holes)? · Standard part · basis: ASME B16.5 Class 300 dimensions as printed in manufacturer and distributor tables (Texas Flange, inch; cross-checked against a second table in mm); the standard itself is paywalled
Also called: 300# flange dimensions, 300 lb flange dimensions, class 300 flange dimensions, 2 inch class 300 flange, 300 pound flange size chart, b16.5 class 300, ansi 300 flange, 300# slip on flange, 300# blind flange, 300# flange bolt circle, pipe flange dimensions, ansi flange dimensions, asme b16.5 flange dimensions, slip on flange dimensions, blind flange dimensions, raised face flange dimensions
Exact dimensions. True size, with no printing tolerance added.
- sizes
- 20 in table
Notes
- Weld-neck, slip-on, blind, socket-weld and threaded flanges of one size and class share the flange OD, raised face, bolt circle, bolt holes and bolting; they differ in the hub, bore and length columns. Thickness is the minimum with the 1/16 in raised face included.
- Raised face: 1/16 in (1.6 mm) high on Class 150 and 300. The flat plate is the printed thickness less that 1/16 in.
- Holes are the bolt diameter plus 1/8 in, as the tables state; hole count and bolt diameter match the stud tables. Bolt holes straddle the vertical centreline in the files (the usual layout, not printed in the cited tables).
- Files: for every NPS from ½ to 24, a blind flange and a slip-on flange at true size. The slip-on hub is drawn as a plain cylinder at the printed base diameter to the printed length: the tables do not print a hub taper, so none is drawn. The bore is the printed slip-on bore (pipe OD plus about 1 mm). Class 300 bores at NPS 10, 12, 14, 16, 18, 20, 4, 5, 6, 8: Texas Flange repeats the Class 150 value, the mm table of Project Materials prints a slightly larger one (0.6 to 0.8 mm); the mm table is used for those sizes.
- Not in the files: weld-neck flanges (hub taper and bevel are not printed; the base diameter and length are in the table), socket-weld and threaded flanges (their bore and thread columns are labelled ambiguously in the sources), weld bevels, fillet radii, the serrated finish of the face, and NPS 22 (printed by one source only).
- Tables print inch; millimetres are the inch value × 25.4. The separate metric table of B16.5 rounds some sizes differently (for example NPS 1 Class 150 OD 110 mm against 4.25 in = 108 mm); the inch table is used here.
- Class 150 is on its own page: asme-b16-5-class-150-flanges. Bolt pattern lookup for both classes: asme-b16-5-flange-bolt-patterns.
ASME B16.5 Class 300 pipe flanges, NPS ½ to 24: dimensions, bolt… size chart
| NPS | flange OD, in (mm) | thickness incl. raised face, in (mm) | raised-face dia, in (mm) | bolt circle, in (mm) | holes × hole dia, in | bolt dia, in | hub dia at base, in (mm) | slip-on hub length, in | weld-neck length, in | slip-on bore, in | weld-neck end OD, in |
|---|---|---|---|---|---|---|---|---|---|---|---|
| 1/2 | 3.75 (95.2) | 0.56 (14.3) | 1.38 (34.9) | 2.62 (66.7) | 4 × 0.625 | 0.5 | 1.50 (38.1) | 0.81 | 2.00 | 0.88 | 0.84 |
| 3/4 | 4.62 (117.5) | 0.62 (15.9) | 1.69 (42.9) | 3.25 (82.5) | 4 × 0.75 | 0.625 | 1.88 (47.6) | 0.94 | 2.19 | 1.09 | 1.05 |
| 1 | 4.88 (123.8) | 0.69 (17.5) | 2.00 (50.8) | 3.50 (88.9) | 4 × 0.75 | 0.625 | 2.12 (54.0) | 1.00 | 2.38 | 1.36 | 1.32 |
| 1-1/4 | 5.25 (133.3) | 0.75 (19.0) | 2.50 (63.5) | 3.88 (98.4) | 4 × 0.75 | 0.625 | 2.50 (63.5) | 1.00 | 2.50 | 1.70 | 1.66 |
| 1-1/2 | 6.12 (155.6) | 0.81 (20.6) | 2.88 (73.0) | 4.50 (114.3) | 4 × 0.875 | 0.75 | 2.75 (69.8) | 1.13 | 2.63 | 1.95 | 1.90 |
| 2 | 6.50 (165.1) | 0.88 (22.2) | 3.62 (92.1) | 5.00 (127.0) | 8 × 0.75 | 0.625 | 3.31 (84.1) | 1.25 | 2.69 | 2.44 | 2.38 |
| 2-1/2 | 7.50 (190.5) | 1.00 (25.4) | 4.12 (104.8) | 5.88 (149.2) | 8 × 0.875 | 0.75 | 3.94 (100.0) | 1.44 | 2.94 | 2.94 | 2.88 |
| 3 | 8.25 (209.5) | 1.12 (28.6) | 5.00 (127.0) | 6.62 (168.3) | 8 × 0.875 | 0.75 | 4.62 (117.5) | 1.63 | 3.06 | 3.57 | 3.50 |
| 3-1/2 | 9.00 (228.6) | 1.19 (30.2) | 5.50 (139.7) | 7.25 (184.1) | 8 × 0.875 | 0.75 | 5.25 (133.3) | 1.69 | 3.13 | 4.07 | 4.00 |
| 4 | 10.00 (254.0) | 1.25 (31.8) | 6.19 (157.2) | 7.88 (200.0) | 8 × 0.875 | 0.75 | 5.75 (146.0) | 1.82 | 3.32 | 4.60 | 4.50 |
| 5 | 11.00 (279.4) | 1.38 (34.9) | 7.31 (185.7) | 9.25 (234.9) | 8 × 0.875 | 0.75 | 7.00 (177.8) | 1.94 | 3.82 | 5.68 | 5.56 |
| 6 | 12.50 (317.5) | 1.44 (36.5) | 8.50 (215.9) | 10.62 (269.9) | 12 × 0.875 | 0.75 | 8.12 (206.4) | 2.00 | 3.82 | 6.75 | 6.63 |
| 8 | 15.00 (381.0) | 1.62 (41.3) | 10.62 (269.9) | 13.00 (330.2) | 12 × 1 | 0.875 | 10.25 (260.3) | 2.38 | 4.32 | 8.75 | 8.63 |
| 10 | 17.50 (444.5) | 1.88 (47.6) | 12.75 (323.8) | 15.25 (387.3) | 16 × 1.125 | 1 | 12.62 (320.7) | 2.56 | 4.56 | 10.92 | 10.75 |
| 12 | 20.50 (520.7) | 2.00 (50.8) | 15.00 (381.0) | 17.75 (450.8) | 16 × 1.25 | 1.125 | 14.75 (374.6) | 2.82 | 5.06 | 12.92 | 12.75 |
| 14 | 23.00 (584.2) | 2.12 (54.0) | 16.25 (412.8) | 20.25 (514.4) | 20 × 1.25 | 1.125 | 16.75 (425.4) | 2.94 | 5.56 | 14.18 | 14.00 |
| 16 | 25.50 (647.7) | 2.25 (57.1) | 18.50 (469.9) | 22.50 (571.5) | 20 × 1.375 | 1.25 | 19.00 (482.6) | 3.19 | 5.69 | 16.19 | 16.00 |
| 18 | 28.00 (711.2) | 2.38 (60.3) | 21.00 (533.4) | 24.75 (628.6) | 24 × 1.375 | 1.25 | 21.00 (533.4) | 3.44 | 6.19 | 18.20 | 18.00 |
| 20 | 30.50 (774.7) | 2.50 (63.5) | 23.00 (584.2) | 27.00 (685.8) | 24 × 1.375 | 1.25 | 23.12 (587.4) | 3.69 | 6.32 | 20.25 | 20.00 |
| 24 | 36.00 (914.4) | 2.75 (69.8) | 27.25 (692.1) | 32.00 (812.8) | 24 × 1.625 | 1.5 | 27.62 (701.7) | 4.13 | 6.56 | 24.25 | 24.00 |
Where the files are
Other publishers' files are linked, not hosted. "verify" = check the license at the link before commercial use.
| Texas Flange | ANSI B16.5 Class 300 forged flange dimensions (inch) | web | Publisher's page; dimensions are facts |
| Thermometrics | Class 300 flanges: dimensions and weights (inch) | web | Publisher's page; dimensions are facts |
| Wermac | Stud bolts for ASME B16.5 Class 300 flanges (inch) | web | Publisher's page; dimensions are facts |
| Project Materials | Slip-on flange dimensions ASME B16.5 Class 150 and 300 (mm) | web | Publisher's page; dimensions are facts |
Free files
★ Free files 40 parts. Generated by Xem Studio from the standard; threads are plain cylinders at major diameter. CC BY 4.0. index.json
| flange-300-nps0p5-blind | Blind flange, NPS 1/2 Class 300: OD 95.2 mm, raised face dia 34.9 x 1.6 mm, bolt circle 66.7 mm, 4 holes dia 15.9 mm for 0.5 in bolts; thickness 14.3 mm including the raised face | STEP · STL |
| flange-300-nps0p5-slip-on | Slip-on flange, NPS 1/2 Class 300: OD 95.2 mm, raised face dia 34.9 x 1.6 mm, bolt circle 66.7 mm, 4 holes dia 15.9 mm for 0.5 in bolts; bore 22.4 mm, hub dia 38.1 mm drawn straight, length 20.6 mm from the raised face to the hub end | STEP · STL |
| flange-300-nps0p75-blind | Blind flange, NPS 3/4 Class 300: OD 117.5 mm, raised face dia 42.9 x 1.6 mm, bolt circle 82.5 mm, 4 holes dia 19.0 mm for 0.625 in bolts; thickness 15.9 mm including the raised face | STEP · STL |
| flange-300-nps0p75-slip-on | Slip-on flange, NPS 3/4 Class 300: OD 117.5 mm, raised face dia 42.9 x 1.6 mm, bolt circle 82.5 mm, 4 holes dia 19.0 mm for 0.625 in bolts; bore 27.7 mm, hub dia 47.6 mm drawn straight, length 23.9 mm from the raised face to the hub end | STEP · STL |
| flange-300-nps1-blind | Blind flange, NPS 1 Class 300: OD 123.8 mm, raised face dia 50.8 x 1.6 mm, bolt circle 88.9 mm, 4 holes dia 19.0 mm for 0.625 in bolts; thickness 17.5 mm including the raised face | STEP · STL |
| flange-300-nps1-slip-on | Slip-on flange, NPS 1 Class 300: OD 123.8 mm, raised face dia 50.8 x 1.6 mm, bolt circle 88.9 mm, 4 holes dia 19.0 mm for 0.625 in bolts; bore 34.5 mm, hub dia 54.0 mm drawn straight, length 25.4 mm from the raised face to the hub end | STEP · STL |
| flange-300-nps1p25-blind | Blind flange, NPS 1-1/4 Class 300: OD 133.3 mm, raised face dia 63.5 x 1.6 mm, bolt circle 98.4 mm, 4 holes dia 19.0 mm for 0.625 in bolts; thickness 19.0 mm including the raised face | STEP · STL |
| flange-300-nps1p25-slip-on | Slip-on flange, NPS 1-1/4 Class 300: OD 133.3 mm, raised face dia 63.5 x 1.6 mm, bolt circle 98.4 mm, 4 holes dia 19.0 mm for 0.625 in bolts; bore 43.2 mm, hub dia 63.5 mm drawn straight, length 25.4 mm from the raised face to the hub end | STEP · STL |
| flange-300-nps1p5-blind | Blind flange, NPS 1-1/2 Class 300: OD 155.6 mm, raised face dia 73.0 x 1.6 mm, bolt circle 114.3 mm, 4 holes dia 22.2 mm for 0.75 in bolts; thickness 20.6 mm including the raised face | STEP · STL |
| flange-300-nps1p5-slip-on | Slip-on flange, NPS 1-1/2 Class 300: OD 155.6 mm, raised face dia 73.0 x 1.6 mm, bolt circle 114.3 mm, 4 holes dia 22.2 mm for 0.75 in bolts; bore 49.5 mm, hub dia 69.8 mm drawn straight, length 28.7 mm from the raised face to the hub end | STEP · STL |
| flange-300-nps2-blind | Blind flange, NPS 2 Class 300: OD 165.1 mm, raised face dia 92.1 x 1.6 mm, bolt circle 127.0 mm, 8 holes dia 19.0 mm for 0.625 in bolts; thickness 22.2 mm including the raised face | STEP · STL |
| flange-300-nps2-slip-on | Slip-on flange, NPS 2 Class 300: OD 165.1 mm, raised face dia 92.1 x 1.6 mm, bolt circle 127.0 mm, 8 holes dia 19.0 mm for 0.625 in bolts; bore 62.0 mm, hub dia 84.1 mm drawn straight, length 31.8 mm from the raised face to the hub end | STEP · STL |
| flange-300-nps2p5-blind | Blind flange, NPS 2-1/2 Class 300: OD 190.5 mm, raised face dia 104.8 x 1.6 mm, bolt circle 149.2 mm, 8 holes dia 22.2 mm for 0.75 in bolts; thickness 25.4 mm including the raised face | STEP · STL |
| flange-300-nps2p5-slip-on | Slip-on flange, NPS 2-1/2 Class 300: OD 190.5 mm, raised face dia 104.8 x 1.6 mm, bolt circle 149.2 mm, 8 holes dia 22.2 mm for 0.75 in bolts; bore 74.7 mm, hub dia 100.0 mm drawn straight, length 36.6 mm from the raised face to the hub end | STEP · STL |
| flange-300-nps3-blind | Blind flange, NPS 3 Class 300: OD 209.5 mm, raised face dia 127.0 x 1.6 mm, bolt circle 168.3 mm, 8 holes dia 22.2 mm for 0.75 in bolts; thickness 28.6 mm including the raised face | STEP · STL |
| flange-300-nps3-slip-on | Slip-on flange, NPS 3 Class 300: OD 209.5 mm, raised face dia 127.0 x 1.6 mm, bolt circle 168.3 mm, 8 holes dia 22.2 mm for 0.75 in bolts; bore 90.7 mm, hub dia 117.5 mm drawn straight, length 41.4 mm from the raised face to the hub end | STEP · STL |
| flange-300-nps3p5-blind | Blind flange, NPS 3-1/2 Class 300: OD 228.6 mm, raised face dia 139.7 x 1.6 mm, bolt circle 184.1 mm, 8 holes dia 22.2 mm for 0.75 in bolts; thickness 30.2 mm including the raised face | STEP · STL |
| flange-300-nps3p5-slip-on | Slip-on flange, NPS 3-1/2 Class 300: OD 228.6 mm, raised face dia 139.7 x 1.6 mm, bolt circle 184.1 mm, 8 holes dia 22.2 mm for 0.75 in bolts; bore 103.4 mm, hub dia 133.3 mm drawn straight, length 42.9 mm from the raised face to the hub end | STEP · STL |
| flange-300-nps4-blind | Blind flange, NPS 4 Class 300: OD 254.0 mm, raised face dia 157.2 x 1.6 mm, bolt circle 200.0 mm, 8 holes dia 22.2 mm for 0.75 in bolts; thickness 31.8 mm including the raised face | STEP · STL |
| flange-300-nps4-slip-on | Slip-on flange, NPS 4 Class 300: OD 254.0 mm, raised face dia 157.2 x 1.6 mm, bolt circle 200.0 mm, 8 holes dia 22.2 mm for 0.75 in bolts; bore 116.8 mm, hub dia 146.0 mm drawn straight, length 46.2 mm from the raised face to the hub end | STEP · STL |
| flange-300-nps5-blind | Blind flange, NPS 5 Class 300: OD 279.4 mm, raised face dia 185.7 x 1.6 mm, bolt circle 234.9 mm, 8 holes dia 22.2 mm for 0.75 in bolts; thickness 34.9 mm including the raised face | STEP · STL |
| flange-300-nps5-slip-on | Slip-on flange, NPS 5 Class 300: OD 279.4 mm, raised face dia 185.7 x 1.6 mm, bolt circle 234.9 mm, 8 holes dia 22.2 mm for 0.75 in bolts; bore 144.4 mm, hub dia 177.8 mm drawn straight, length 49.3 mm from the raised face to the hub end | STEP · STL |
| flange-300-nps6-blind | Blind flange, NPS 6 Class 300: OD 317.5 mm, raised face dia 215.9 x 1.6 mm, bolt circle 269.9 mm, 12 holes dia 22.2 mm for 0.75 in bolts; thickness 36.5 mm including the raised face | STEP · STL |
| flange-300-nps6-slip-on | Slip-on flange, NPS 6 Class 300: OD 317.5 mm, raised face dia 215.9 x 1.6 mm, bolt circle 269.9 mm, 12 holes dia 22.2 mm for 0.75 in bolts; bore 171.4 mm, hub dia 206.4 mm drawn straight, length 50.8 mm from the raised face to the hub end | STEP · STL |
| flange-300-nps8-blind | Blind flange, NPS 8 Class 300: OD 381.0 mm, raised face dia 269.9 x 1.6 mm, bolt circle 330.2 mm, 12 holes dia 25.4 mm for 0.875 in bolts; thickness 41.3 mm including the raised face | STEP · STL |
| flange-300-nps8-slip-on | Slip-on flange, NPS 8 Class 300: OD 381.0 mm, raised face dia 269.9 x 1.6 mm, bolt circle 330.2 mm, 12 holes dia 25.4 mm for 0.875 in bolts; bore 222.2 mm, hub dia 260.3 mm drawn straight, length 60.5 mm from the raised face to the hub end | STEP · STL |
| flange-300-nps10-blind | Blind flange, NPS 10 Class 300: OD 444.5 mm, raised face dia 323.8 x 1.6 mm, bolt circle 387.3 mm, 16 holes dia 28.6 mm for 1 in bolts; thickness 47.6 mm including the raised face | STEP · STL |
| flange-300-nps10-slip-on | Slip-on flange, NPS 10 Class 300: OD 444.5 mm, raised face dia 323.8 x 1.6 mm, bolt circle 387.3 mm, 16 holes dia 28.6 mm for 1 in bolts; bore 277.4 mm, hub dia 320.7 mm drawn straight, length 65.0 mm from the raised face to the hub end | STEP · STL |
| flange-300-nps12-blind | Blind flange, NPS 12 Class 300: OD 520.7 mm, raised face dia 381.0 x 1.6 mm, bolt circle 450.8 mm, 16 holes dia 31.8 mm for 1.125 in bolts; thickness 50.8 mm including the raised face | STEP · STL |
| flange-300-nps12-slip-on | Slip-on flange, NPS 12 Class 300: OD 520.7 mm, raised face dia 381.0 x 1.6 mm, bolt circle 450.8 mm, 16 holes dia 31.8 mm for 1.125 in bolts; bore 328.2 mm, hub dia 374.6 mm drawn straight, length 71.6 mm from the raised face to the hub end | STEP · STL |
| flange-300-nps14-blind | Blind flange, NPS 14 Class 300: OD 584.2 mm, raised face dia 412.8 x 1.6 mm, bolt circle 514.4 mm, 20 holes dia 31.8 mm for 1.125 in bolts; thickness 54.0 mm including the raised face | STEP · STL |
| flange-300-nps14-slip-on | Slip-on flange, NPS 14 Class 300: OD 584.2 mm, raised face dia 412.8 x 1.6 mm, bolt circle 514.4 mm, 20 holes dia 31.8 mm for 1.125 in bolts; bore 360.2 mm, hub dia 425.4 mm drawn straight, length 74.7 mm from the raised face to the hub end | STEP · STL |
| flange-300-nps16-blind | Blind flange, NPS 16 Class 300: OD 647.7 mm, raised face dia 469.9 x 1.6 mm, bolt circle 571.5 mm, 20 holes dia 34.9 mm for 1.25 in bolts; thickness 57.1 mm including the raised face | STEP · STL |
| flange-300-nps16-slip-on | Slip-on flange, NPS 16 Class 300: OD 647.7 mm, raised face dia 469.9 x 1.6 mm, bolt circle 571.5 mm, 20 holes dia 34.9 mm for 1.25 in bolts; bore 411.2 mm, hub dia 482.6 mm drawn straight, length 81.0 mm from the raised face to the hub end | STEP · STL |
| flange-300-nps18-blind | Blind flange, NPS 18 Class 300: OD 711.2 mm, raised face dia 533.4 x 1.6 mm, bolt circle 628.6 mm, 24 holes dia 34.9 mm for 1.25 in bolts; thickness 60.3 mm including the raised face | STEP · STL |
| flange-300-nps18-slip-on | Slip-on flange, NPS 18 Class 300: OD 711.2 mm, raised face dia 533.4 x 1.6 mm, bolt circle 628.6 mm, 24 holes dia 34.9 mm for 1.25 in bolts; bore 462.3 mm, hub dia 533.4 mm drawn straight, length 87.4 mm from the raised face to the hub end | STEP · STL |
| flange-300-nps20-blind | Blind flange, NPS 20 Class 300: OD 774.7 mm, raised face dia 584.2 x 1.6 mm, bolt circle 685.8 mm, 24 holes dia 34.9 mm for 1.25 in bolts; thickness 63.5 mm including the raised face | STEP · STL |
| flange-300-nps20-slip-on | Slip-on flange, NPS 20 Class 300: OD 774.7 mm, raised face dia 584.2 x 1.6 mm, bolt circle 685.8 mm, 24 holes dia 34.9 mm for 1.25 in bolts; bore 514.4 mm, hub dia 587.4 mm drawn straight, length 93.7 mm from the raised face to the hub end | STEP · STL |
| flange-300-nps24-blind | Blind flange, NPS 24 Class 300: OD 914.4 mm, raised face dia 692.1 x 1.6 mm, bolt circle 812.8 mm, 24 holes dia 41.3 mm for 1.5 in bolts; thickness 69.8 mm including the raised face | STEP · STL |
| flange-300-nps24-slip-on | Slip-on flange, NPS 24 Class 300: OD 914.4 mm, raised face dia 692.1 x 1.6 mm, bolt circle 812.8 mm, 24 holes dia 41.3 mm for 1.5 in bolts; bore 615.9 mm, hub dia 701.7 mm drawn straight, length 104.9 mm from the raised face to the hub end | STEP · STL |
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Questions
What is the OD of a 2 inch Class 300 flange?
6.50 in (165.1 mm), with a 8-hole 5.000 in bolt circle.
What is the bolt circle of a 4 inch Class 300 flange?
7.875 in (200.0 mm), 8 holes of 0.875 in for 0.75 in bolts.
How high is the raised face on a Class 300 flange?
1/16 in (1.6 mm); it is included in the printed flange thickness.
Do slip-on, blind and weld-neck flanges share bolt patterns?
Yes: for the same NPS and class the OD, bolt circle and holes are the same; hub, bore and length differ.