Blind Flanges
Certified steel products, dependable supply and application-focused support for industrial buyers.
Blind flanges are used to close pipe ends, valves and pressure vessel openings for inspection, isolation and future expansion. They are selected where positive shut-off, pressure holding and access for future maintenance are required. We supply blind flanges with controlled face finish, accurate bolt holes and material grades suitable for corrosive, high-temperature and general industrial service.
Size Range1/2 inch to 48 inch
Wall / Pressure ClassClass
150/300/600/900/1500/2500
TypesRaised Face, Flat Face, RTJ
Blind
StandardsASME B16.5, ASME
B16.47
FinishSerrated, Smooth, Galvanized,
Coated
LengthStandard thickness
Materials Grades
Available in corrosion-resistant, high-temperature and pressure-grade materials for industrial service. Grade selection can be aligned with pressure, temperature, corrosion allowance and client specification.
Stainless Steel 304/304LStainless Steel 316/316LCarbon SteelAlloy
SteelDuplex 2205Super Duplex 2507InconelMonelHastelloyTitanium
Dimensions Chart
Covers nominal size, outside diameter, bolt circle, hole quantity and flange thickness.
Class 150 Blind Flange Dimensions
| NPS (Normal Pipe Sizes) | "A" (O.D.) Outside Daimeter |
"B" (Thickness) |
"C" (RF Daimeter) |
"D" (B.C.D.) |
# Bolt Holes |
Daimeter of Bolt Holes |
Approx. Weight In Kg |
|---|---|---|---|---|---|---|---|
| 1/2" | 3-1/2 | 7/16 | 1-3/8 | 2-3/8 | 4 | 5/8 | 2 |
| 3/4" | 3-7/8 | 1/2 | 1-11/16 | 2-3/4 | 4 | 5/8 | 2 |
| 1" | 4-1/4 | 9/16 | 2 | 3-1/8 | 4 | 5/8 | 2 |
| 1-1/4" | 4-5/8 | 5/8 | 2-1/2 | 3-1/2 | 4 | 5/8 | 3 |
| 1-1/2" | 5 | 11/16 | 2-7/8 | 3-7/8 | 4 | 5/8 | 3 |
| 2" | 6 | 3/4 | 3-5/8 | 4-3/4 | 4 | 3/4 | 4 |
| 2-1/2" | 7 | 7/8 | 4-1/8 | 5-1/2 | 4 | 3/4 | 7 |
| 3" | 7-1/2 | 15/16 | 5 | 6 | 4 | 3/4 | 9 |
| 3-1/2" | 8-1/2 | 15/16 | 5-1/2 | 7 | 8 | 3/4 | 13 |
| 4" | 9 | 15/16 | 6-3/16 | 7-1/2 | 8 | 3/4 | 17 |
| 5" | 10 | 15/16 | 7-5/16 | 8-1/2 | 8 | 7/8 | 20 |
| 6" | 11 | 1 | 8-1/2 | 9-1/2 | 8 | 7/8 | 27 |
| 8" | 13-1/2 | 1-1/8 | 10-5/8 | 11-3/4 | 8 | 7/8 | 47 |
| 10" | 16 | 1-3/16 | 12-3/4 | 14-1/4 | 12 | 1 | 67 |
| 12" | 19 | 1-1/4 | 15 | 17 | 12 | 1 | 123 |
| 14" | 21 | 1-3/8 | 16-1/4 | 18-3/4 | 12 | 1-1/8 | 139 |
| 16" | 23-1/2 | 1-7/16 | 18-1/2 | 21-1/4 | 16 | 1-1/8 | 187 |
| 18" | 25 | 1-9/16 | 21 | 22-3/4 | 16 | 1-1/4 | 217 |
| 20" | 27-1/2 | 1-11/16 | 23 | 25 | 20 | 1-1/4 | 283 |
| 24" | 32 | 1-7/8 | 27-1/4 | 29-1/2 | 20 | 1-3/8 | 415 |
Class 300 Blind Flange Dimensions
| NPS (Normal Pipe Size) | "A" (O.D.) Ouside Daimeter |
"B" (Thickness) |
"C" (RF Daimeter) |
"D" (B.C.D.) |
# Bolt Holes |
Daimeter of Bolt Holes |
Approx. Weight in Kilogram |
|---|---|---|---|---|---|---|---|
| 1/2" | 3-3/4 | 9/16 | 1-3/8 | 2-5/8 | 4 | 5/8 | 2 |
| 3/4" | 4-5/8 | 5/8 | 1-11/16 | 3-1/4 | 4 | 3/4 | 3 |
| 1" | 4-7/8 | 11/16 | 2 | 3-1/2 | 4 | 3/4 | 4 |
| 1-1/4" | 5-1/4 | 3/4 | 2-1/2 | 3-7/8 | 4 | 3/4 | 6 |
| 1-1/2" | 6-1/8 | 13/16 | 2-7/8 | 4-1/2 | 4 | 7/8 | 7 |
| 2" | 6-1/2 | 7/8 | 3-5/8 | 5 | 8 | 3/4 | 8 |
| 2-1/2" | 7-1/2 | 1 | 4-1/8 | 5-7/8 | 8 | 7/8 | 12 |
| 3" | 8-1/4 | 1-1/8 | 5 | 6-5/8 | 8 | 7/8 | 16 |
| 3-1/2" | 9 | 1-3/16 | 5-1/2 | 7-1/4 | 8 | 7/8 | 21 |
| 4" | 10 | 1-1/4 | 6-3/16 | 7-7/8 | 8 | 7/8 | 28 |
| 5" | 11 | 1-3/8 | 7-5/16 | 9-1/4 | 8 | 7/8 | 37 |
| 6" | 12-1/2 | 1-7/16 | 8-1/2 | 10-5/8 | 12 | 7/8 | 48 |
| 8" | 15 | 1-5/8 | 10-5/8 | 13 | 12 | 1 | 79 |
| 10" | 17-1/2 | 1-7/8 | 12-3/4 | 15-1/4 | 16 | 1-1/8 | 122 |
| 12" | 20-1/2 | 2 | 15 | 17-3/4 | 16 | 1-1/4 | 183 |
| 14" | 23 | 2-1/8 | 16-1/4 | 20-1/4 | 20 | 1-1/4 | 241 |
| 16" | 25-1/2 | 2-1/4 | 18-1/2 | 22-1/2 | 20 | 1-3/8 | 315 |
| 18" | 28 | 2-3/8 | 21 | 24-3/4 | 24 | 1-3/8 | 414 |
| 20" | 30-1/2 | 2-1/2 | 23 | 27 | 24 | 1-3/8 | 515 |
| 24" | 36 | 2-3/4 | 27-1/4 | 32 | 24 | 1-5/8 | 800 |
Class 400 Blind Flange Dimensions
| NPS (Normal Pipe Sizes) | Outside Daimeter | Circle Of Bolt (BC) | Raised Face (R) | Raised Face (RF) | Thickness Of Raised Face (T) | Thickness Of Flat Face (T2) | Hole Of Bolt (B) | Number of Bolt Holes | ||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| 1/2" | 3.75" | 2.62" | 0.12" | .250" | 0.81" | 0.56" | 0.62" | 4 | ||||||
| 3/4" | 4.62" | 3.25" | 0.12" | .250" | 0.87" | 0.62" | 0.75" | 4 | ||||||
| 1" | 4.88" | 3.50" | 0.12" | .250" | 0.94" | 0.69" | 0.75" | 4 | ||||||
| 1-1/4" | 5.25" | 3.88" | 0.19" | .250" | 1.06" | 0.81" | 0.75" | 4 | ||||||
| 1-1/2" | 6.12" | 4.50" | 0.25" | .250" | 1.13" | 0.88" | 0.88" | 4 | ||||||
| 2" | 6.50" | 5.00" | 0.31" | .250" | 1.25" | 1.00" | 0.75" | 8 | ||||||
| 2-1/2" | 7.50" | 5.88" | 0.31" | .250" | 1.37" | 1.12" | 0.88" | 8 | ||||||
| 3" | 8.25" | 6.62" | 0.38" | .250" | 1.50" | 1.25" | 0.88" | 8 | ||||||
| 3-1/2" | 9.00" | 7.25" | 0.38" | .250" | 1.63" | 1.38" | 1.00" | 8 | ||||||
| 4" | 10.00" | 7.88" | 0.44" | .250" | 1.63" | 1.38" | 1.00" | 8 | ||||||
| 5" | 11.00" | 9.25" | 0.44" | .250" | 1.75" | 1.50" | 1.00" | 8 | ||||||
| 6" | 12.50" | 10.62" | 0.50" | .250" | 1.87" | 1.62" | 1.00" | 12 | ||||||
| 8" | 15.00" | 13.00" | 0.50" | .250" | 2.13" | 1.88" | 1.12" | 12 | ||||||
| 10" | 17.50" | 15.25" | 0.50" | .250" | 2.37" | 2.12" | 1.25" | 16 | ||||||
| 12" | 20.50" | 17.75" | 0.50" | .250" | 2.50" | 2.25" | 1.38" | 16 | ||||||
| 14" | 23.00" | 20.25" | 0.50" | .250" | 2.63" | 2.38" | 1.38" | 20 | ||||||
| 16" | 25.50" | 22.50" | 0.50" | .250" | 2.75" | 2.50" | 1.50" | 20 | ||||||
| 18" | 28.00" | 24.75" | 0.50" | .250" | 2.87" | 2.62" | 1.50" | 24 | ||||||
| 20" | 30.50" | 27.00" | 0.50" | .250" | 3.00" | 2.75" | 1.62" | 24 | ||||||
| 22" | 33.00" | 29.25" | 0.50" | .250" | 3.13" | 2.88" | 1.75" | 24 | ||||||
| 24" | 36.00" | 32.00" | 0.50" | .250" | 3.25" | 3.00" | 1.88" | 24 |
Class 600 Blind Flange Dimensions
| ΓΈ | D | b | g | k | Holes | l | Kg. |
|---|---|---|---|---|---|---|---|
| 1/2" | 95,2 | 14,3 | 34,9 | 66,7 | 4 | 15,9 | 0,700 |
| 3/4" | 117,5 | 15,9 | 42,9 | 82,5 | 4 | 19,0 | 1,200 |
| 1" | 123,8 | 17,5 | 50,8 | 88,9 | 4 | 19,0 | 1,500 |
| 1 1/4" | 133,3 | 20,6 | 63,5 | 98,4 | 4 | 19,0 | 2,000 |
| 1 1/2" | 155,6 | 22,2 | 73,0 | 114,3 | 4 | 22,2 | 3,200 |
| 2" | 165,1 | 25,4 | 92,1 | 127,0 | 8 | 19,0 | 4,300 |
| 2 1/2" | 190,5 | 28,6 | 104,8 | 149,2 | 8 | 22,2 | 6,000 |
| 3" | 209,5 | 31,7 | 127,0 | 168,3 | 8 | 22,2 | 8,000 |
| 3 1/2" | 228,6 | 34,9 | 139,7 | 184,1 | 8 | 25,4 | 10,500 |
| 4" | 273,0 | 38,1 | 157,2 | 215,9 | 8 | 25,4 | 18,000 |
| 5" | 330,2 | 44,4 | 185,7 | 266,7 | 8 | 28,6 | 28,500 |
| 6" | 355,6 | 47,6 | 215,9 | 292,1 | 12 | 28,6 | 35,500 |
| 8" | 419,1 | 55,6 | 269,9 | 349,2 | 12 | 31,7 | 58,000 |
| 10" | 508,0 | 63,5 | 323,8 | 431,8 | 16 | 34,9 | 98,000 |
| 12" | 558,8 | 66,7 | 381,0 | 488,9 | 20 | 34,9 | 125,000 |
| 14" | 603,2 | 69,8 | 412,7 | 527,0 | 20 | 38,1 | 151,000 |
| 16" | 685,8 | 76,2 | 469,9 | 603,2 | 20 | 41,3 | 215,000 |
| 18" | 742,9 | 82,5 | 533,4 | 654,0 | 20 | 44,4 | 287,000 |
| 20" | 812,8 | 88,9 | 584,2 | 723,9 | 24 | 44,4 | 366,000 |
| 22" | 869,9 | 95,2 | 641,2 | 777,9 | 24 | 47,6 | 437,000 |
| 24" | 939,8 | 101,6 | 692,1 | 838,2 | 24 | 50,8 | 532,000 |
Class 900 Blind Flange Dimensions
| NPS (Normal Pipe Size) | O.D. (Outside Daimeter) | Circle Of Bolt (BC) | Raised Face (R) | Raised Face (RF) | Thickness Of Raised Face (T) | Thickness Of Flat Face (T2) | Hole Of Bolt (B) | Number of Bolt Holes |
|---|---|---|---|---|---|---|---|---|
| 3" | 9.50" | 7.50" | 5.00" | .250" | 1.75" | 1.50" | 1.00" | 8 |
| 4" | 11.50" | 9.25" | 6.19" | .250" | 2.00" | 1.75" | 1.25" | 8 |
| 5" | 13.75" | 11.00" | 7.31" | .250" | 3.25" | 3.00" | 1.38" | 8 |
| 6" | 15.00" | 12.50" | 8.50" | .250" | 2.44" | 2.19" | 1.25" | 12 |
| 8" | 18.50" | 15.50" | 10.63" | .250" | 2.75" | 2.50" | 1.50" | 12 |
| 10" | 21.50" | 18.50" | 12.75" | .250" | 3.00" | 2.75" | 1.50" | 16 |
| 12" | 24.00" | 21.00" | 15.00" | .250" | 3.38" | 3.13" | 1.50" | 20 |
| 14" | 25.25" | 22.00" | 16.25" | .250" | 3.63" | 3.38" | 1.63" | 20 |
| 16" | 27.75" | 24.25" | 18.50" | .250" | 3.75" | 3.50" | 1.75" | 20 |
| 18" | 31.00" | 27.00" | 21.00" | .250" | 4.25" | 4.00" | 2.00" | 20 |
| 20" | 33.75" | 29.50" | 23.00" | .250" | 4.50" | 4.25" | 2.13" | 20 |
| 24" | 41.00" | 35.50" | 27.25" | .250" | 5.75" | 5.50" | 2.63" | 20 |
Class 1500 Blind Flange Dimensions
| NPS | Outside Daimeter Flange | Thickness Of Flange Minimum | Daimeter of Hub | Daimeter of Bolt Circle | Daimeter of Bolt Holes | Number of Bolts | Daimeter of Bolts(inches) | Approx. Weight in kilogram | ||
|---|---|---|---|---|---|---|---|---|---|---|
| inches | dn | O | C | X | BC | BH | BN | BD | KG/PCS | LB/PCS |
| 1/2 | 15 | 120.7 | 22.4 | 38.1 | 82.6 | 22.4 | 4 | 3/4 | 1.9 | 4.2 |
| 3/4 | 20 | 130 | 25.4 | 44.5 | 88.9 | 22.4 | 4 | 3/4 | 2.7 | 6 |
| 1 | 25 | 149.4 | 28.4 | 52.3 | 101.6 | 25.4 | 4 | 7/8 | 3.7 | 8.1 |
| 1-1/4 | 32 | 158.8 | 28.4 | 63.5 | 111.3 | 25.4 | 4 | 7/8 | 4.3 | 9.5 |
| 1-1/2 | 40 | 177.8 | 31.8 | 69.9 | 124 | 28.4 | 4 | 1 | 5.9 | 13 |
| 2 | 50 | 215.9 | 38.1 | 104.6 | 165.1 | 25.4 | 8 | 7/8 | 11.3 | 24.9 |
| 2-1/2 | 65 | 244.3 | 41.1 | 124 | 190.5 | 28.4 | 8 | 1 | 16 | 35.2 |
| 3 | 80 | 266.7 | 47.8 | 133.4 | 190.5 | 25.4 | 8 | 7/8 | 19.5 | 43 |
| 4 | 100 | 311.2 | 53.8 | 162.1 | 235 | 31.8 | 8 | 1 1/8 | 33 | 72.8 |
| 5 | 125 | 374.7 | 73.2 | 196.9 | 279.4 | 35.1 | 8 | 1 1/4 | 60 | 132 |
| 6 | 150 | 393.7 | 82.6 | 228.6 | 317.5 | 31.8 | 12 | 1 1/8 | 75 | 165 |
| 8 | 200 | 482.6 | 91.9 | 292.1 | 393.7 | 38.1 | 12 | 1 3/8 | 125 | 275 |
| 10 | 250 | 584.2 | 108 | 368.3 | 469.9 | 38.1 | 16 | 1 3/8 | 215 | 474 |
| 12 | 300 | 673.1 | 124 | 450.9 | 533.4 | 38.1 | 20 | 1 3/8 | 316 | 697 |
| 14 | 350 | 749.3 | 133.4 | 495.3 | 558.8 | 41.1 | 20 | 1 1/2 | ||
| 16 | 400 | 825.5 | 146.1 | 552.5 | 616 | 44.5 | 20 | 1 5/8 | ||
| 18 | 450 | 914.4 | 162.1 | 596.9 | 685.8 | 50.8 | 20 | 1 7/8 | ||
| 20 | 500 | 984.3 | 177.8 | 641.4 | 749.3 | 53.8 | 20 | 2 | ||
| 24 | 600 | 1168.4 | 203.2 | 762 | 901.7 | 66.5 | 20 | 2 1/2 | ||
Class 2500 Blind Flange Dimensions
| NPS | Outside Daimeter Of Flange | Thickness Of Flange Minimum | Daimeter of Bolt Circle | Daimeter of Bolt Holes | Number of Bolts | Daimeter of Bolts (inches) | KG | LB | |
|---|---|---|---|---|---|---|---|---|---|
| inch | dn | O | C | BC | BH | BN | BD | ||
| 1/2 | 15 | 133.4 | 30.2 | 88.9 | 22.4 | 4 | 3/4 | 3 | 7 |
| 3/4 | 20 | 139.7 | 31.8 | 95.3 | 22.4 | 4 | 3/4 | 4.5 | 10 |
| 1 | 25 | 158.8 | 35.1 | 108 | 25.4 | 4 | 7/8 | 5 | 12 |
| 1-1/4 | 32 | 184.2 | 38.1 | 130 | 28.4 | 4 | 1 | 8 | 18 |
| 1-1/2 | 40 | 203.2 | 44.5 | 146.1 | 31.8 | 4 | 1 1/8 | 11 | 25 |
| 2 | 50 | 235 | 50.8 | 171.5 | 28.4 | 8 | 1 | 17 | 38 |
| 2-1/2 | 65 | 266.7 | 57.2 | 196.9 | 31.8 | 8 | 1 1/8 | 25 | 55 |
| 3 | 80 | 304.8 | 66.5 | 228.6 | 35.1 | 8 | 1 1/4 | 39 | 86 |
| 4 | 100 | 355.6 | 76.2 | 273.1 | 41.1 | 8 | 1 1/2 | 60 | 133 |
| 5 | 125 | 419.1 | 91.9 | 323.9 | 47.8 | 8 | 1 3/4 | 101 | 223 |
| 6 | 150 | 482.6 | 108 | 368.3 | 53.8 | 8 | 2 | 156 | 345 |
| 8 | 200 | 552.5 | 127 | 438.2 | 53.8 | 12 | 2 | 242 | 533 |
| 10 | 250 | 673.1 | 165.1 | 539.8 | 66.5 | 12 | 2 1/2 | 465 | 1023 |
| 12 | 300 | 762 | 184.2 | 619.3 | 73.2 | 12 | 2 3/4 | 665 | 1463 |
Applications
Oil & Gas
Reliable performance for demanding fabrication, maintenance and process piping needs.
Petrochemical
Reliable performance for demanding fabrication, maintenance and process piping needs.
Power & Energy
Reliable performance for demanding fabrication, maintenance and process piping needs.
Marine
Reliable performance for demanding fabrication, maintenance and process piping needs.
Chemical
Reliable performance for demanding fabrication, maintenance and process piping needs.
Construction
Reliable performance for demanding fabrication, maintenance and process piping needs.
