Threaded Flange
Threaded Flange: Specifications | Materials | Types | Dimensions | Weight Chart | Tolerances | FAQ
ANSI/ASME B16.5 Threaded Flanges – Manufacturer & Exporter of Carbon, Stainless, Alloy & High Nickel Alloys | Sizes ½”–24”, Pressure Ratings 150#–2500# | Shipped to India, Singapore, Malaysia & Indonesia
Best Export Prices: sales@midlandforgefittings.com
Midland Forge and Fittings Pvt. Ltd. is a trusted manufacturer and exporter of Threaded Flanges designed as per ASME B16.5 and B16.47 standards. Our threaded flanges are engineered for pipelines where welding is not feasible or desirable, making them ideal for small bore, high-pressure systems. With precise machining and strict dimensional tolerances, we ensure leak-proof connections and long-lasting performance across diverse industries.
We offer threaded flanges in carbon steel, stainless steel, alloy steel, duplex, super duplex, and high nickel alloys, ensuring compatibility with various process environments. Available in sizes from ½” to 24” and pressure classes 150# to 2500#.
our threaded flanges are manufactured to withstand demanding conditions such as oil & gas pipelines, chemical processing, petrochemical refineries, and marine systems. Each flange undergoes rigorous quality checks, including PMI, ultrasonic testing, and dimensional inspection, to guarantee reliability.
we are committed to providing high-quality flanges with global reach. Our threaded flanges are exported to major markets across USA, Canada, Europe, Middle East, and Asia, where they are widely appreciated for their durability, precision, and cost-effectiveness. Backed by strong manufacturing expertise and customer-focused service, we continue to be a preferred partner for clients seeking reliable piping solutions with international standards compliance.
THRF Flanges are especially suitable for low-temperature, high-pressure applications where welding might compromise the material properties or where on-site welding is difficult. The threaded connection allows for quick assembly and disassembly without special equipment, making maintenance and modifications easier in the field. At Midland Forge and Fittings Pvt. Ltd., we customize threaded flanges with different thread types (NPT, BSPT, BSPP) and finishes to meet the specific requirements of industries such as power generation, shipbuilding, pharmaceuticals, and water treatment plants.
Threaded Pipe Flange Specifications
Threaded Flange – Materials, Grades & Standards
| Material Category | Standards / Grades (ASTM / ASME) | Pressure Class / Size Range | Typical Use / Application |
|---|---|---|---|
| Stainless Steel | ASTM A182 F304 / F304L / F304H | Class 150 – 2500, Size ½”–48” | General purpose, corrosion-resistant piping |
| ASTM A182 F316 / F316L / F316H | Class 150 – 2500, Size ½”–48” | Chemical, marine, food & pharma industries | |
| ASTM A182 F321 / F321H | Class 150 – 1500, Size ½”–24” | High temperature, stabilized service | |
| Carbon Steel | ASTM A105 (Forged CS) | Class 150 – 2500, Size ½”–48” | Pressure piping, oil & gas, general industries |
| ASTM A350 LF2 (Low Temp CS) | Class 150 – 1500, Size ½”–24” | Cryogenic & low temperature applications | |
| Alloy Steel | ASTM A182 F11 / F22 (Cr-Mo) | Class 150 – 2500, Size ½”–24” | Power plants, refineries, steam pipelines |
| ASTM A182 F91 | Class 150 – 2500, Size ½”–24” | High-temperature, power generation | |
| Duplex / Super Duplex | ASTM A182 F51 / F53 / F55 / F60 (UNS S31803 / S32205 / S32750 / S32760) | Class 150 – 2500, Size ½”–24” | Offshore, seawater, high corrosion service |
| Nickel Alloys | ASTM B564 Inconel 600 / 625 / 718 | Class 150 – 2500, Size ½”–24” | Heat exchangers, chemical, aerospace |
| ASTM B564 Monel 400 / K500 | Class 150 – 2500, Size ½”–24” | Marine, seawater handling, pumps | |
| Copper Nickel | ASTM B151 / B467 (Cu-Ni 90/10, 70/30) | Class 150 – 600, Size ½”–24” | Shipbuilding, desalination, seawater systems |
| Titanium | ASTM B381 Gr. 2 / Gr. 5 | Class 150 – 600, Size ½”–12” | Aerospace, seawater, lightweight piping |
| Aluminium | ASTM B247 6061 / 5083 | Class 150 – 300, Size ½”–12” | Lightweight, non-corrosive, low-pressure piping |
ANSI/ASME B16.5 Class 150 Threaded Flange – Dimensions & Sizes in mm
| Nominal Pipe Size |
Outside Dia of Flange (D) |
Thick of Flange (B) |
Dia of Raised Face (G) |
Dia of Hub at Base (A) |
Length thru Hub (H) |
Min Thread Length (T) |
Min Counter Bore (Q) |
No of Holes |
Dia of Holes (L) |
Dia of Bolts (inch) |
Dia of Bolt Circle (K) |
|---|---|---|---|---|---|---|---|---|---|---|---|
| 1/2 | 88.9 | 11.2 | 35.1 | 30.2 | 15.7 | 15.7 | 4 | 15.7 | 1/2 | 60.5 | |
| 3/4 | 98.6 | 12.7 | 42.9 | 38.1 | 15.7 | 15.7 | 4 | 15.7 | 1/2 | 69.9 | |
| 1 | 108 | 14.2 | 50.8 | 49.3 | 17.5 | 17.5 | 4 | 15.7 | 1/2 | 79.2 | |
| 1-1/4 | 117.3 | 15.7 | 63.5 | 58.7 | 20.6 | 20.6 | 4 | 15.7 | 1/2 | 88.9 | |
| 1-1/2 | 127 | 17.5 | 73.2 | 65 | 22.4 | 22.4 | 4 | 15.7 | 1/2 | 98.6 | |
| 2 | 152.4 | 19.1 | 91.9 | 77.7 | 25.4 | 25.4 | 4 | 19.1 | 5/8 | 120.7 | |
| 2-1/2 | 177.8 | 22.4 | 104.6 | 90.4 | 28.4 | 28.4 | 4 | 19.1 | 5/8 | 139.7 | |
| 3 | 190.5 | 23.9 | 127 | 108 | 30.2 | 30.2 | 4 | 19.1 | 5/8 | 152.4 | |
| 3-1/2 | 215.9 | 23.9 | 139.7 | 122.2 | 31.8 | 31.8 | 8 | 19.1 | 5/8 | 177.8 | |
| 4 | 228.6 | 23.9 | 157.2 | 134.9 | 33.3 | 33.3 | 8 | 19.1 | 5/8 | 190.5 | |
| 5 | 254 | 23.9 | 185.7 | 163.6 | 36.6 | 36.6 | 8 | 22.4 | 3/4 | 215.9 | |
| 6 | 279.4 | 25.4 | 215.9 | 192 | 39.6 | 39.6 | 8 | 22.4 | 3/4 | 241.3 | |
| 8 | 342.9 | 28.4 | 269.7 | 246.1 | 44.5 | 44.5 | 8 | 22.4 | 3/4 | 298.5 | |
| 10 | 406.4 | 30.2 | 323.9 | 304.8 | 49.3 | 49.3 | 12 | 25.4 | 7/8 | 362 | |
| 12 | 482.6 | 31.8 | 381 | 365.3 | 55.6 | 55.6 | 12 | 25.4 | 7/8 | 431.8 | |
| 14 | 533.4 | 35.1 | 412.8 | 400.1 | 57.2 | 57.2 | 12 | 28.4 | 1 | 476.3 | |
| 16 | 596.9 | 36.6 | 469.9 | 457.2 | 63.5 | 63.5 | 16 | 28.4 | 1 | 539.8 | |
| 18 | 635 | 39.6 | 533.4 | 505 | 68.3 | 68.3 | 16 | 31.8 | 1-1/8 | 577.9 | |
| 20 | 698.5 | 42.9 | 584.2 | 558.8 | 73.2 | 73.2 | 20 | 31.8 | 1-1/8 | 635 | |
| 24 | 812.8 | 47.8 | 692.2 | 663.4 | 82.6 | 82.6 | 20 | 35.1 | 1-1/4 | 749.3 |
ANSI/ASME B16.5 Class 300 Threaded Flange – Dimensions & Sizes in mm
| Nominal Pipe Size |
Outside Dia of Flange (D) |
Thick of Flange (B) |
Dia of Raised Face (G) |
Dia of Hub at Base (A) |
Length thru Hub (H) |
Min Thread Length (T) |
Min Counter Bore (Q) |
No of Holes |
Dia of Holes (L) |
Dia of Bolts (inch) |
Dia of Bolt Circle (K) |
|---|---|---|---|---|---|---|---|---|---|---|---|
| 1/2 | 95.3 | 14.2 | 35.1 | 38.1 | 22.4 | 15.7 | 23.6 | 4 | 15.7 | 1/2 | 66.5 |
| 3/4 | 117.3 | 15.7 | 42.9 | 47.8 | 25.4 | 15.7 | 29 | 4 | 19.1 | 5/8 | 82.6 |
| 1 | 124 | 17.5 | 50.8 | 53.8 | 26.9 | 17.5 | 35.8 | 4 | 19.1 | 5/8 | 88.9 |
| 1-1/4 | 133.4 | 19.1 | 63.5 | 63.5 | 26.9 | 20.6 | 44.5 | 4 | 19.1 | 5/8 | 98.6 |
| 1-1/2 | 155.4 | 20.6 | 73.2 | 69.9 | 30.2 | 22.4 | 50.5 | 4 | 22.4 | 3/4 | 114.3 |
| 2 | 165.1 | 22.4 | 91.9 | 84.1 | 33.3 | 28.4 | 63.5 | 8 | 19.1 | 5/8 | 127 |
| 2-1/2 | 190.5 | 25.4 | 104.6 | 100.1 | 38.1 | 31.8 | 76.2 | 8 | 22.4 | 3/4 | 149.4 |
| 3 | 209.6 | 28.4 | 127 | 117.3 | 42.9 | 31.8 | 92.2 | 8 | 22.4 | 3/4 | 168.1 |
| 3-1/2 | 228.6 | 30.2 | 139.7 | 133.4 | 44.5 | 36.6 | 104.9 | 8 | 22.4 | 3/4 | 184.2 |
| 4 | 254 | 31.8 | 157.2 | 146.1 | 47.8 | 36.6 | 117.6 | 8 | 22.4 | 3/4 | 200.2 |
| 5 | 279.4 | 35.1 | 185.7 | 177.8 | 50.8 | 42.9 | 144.5 | 8 | 22.4 | 3/4 | 235 |
| 6 | 317.5 | 36.6 | 215.9 | 206.2 | 52.3 | 46 | 171.5 | 12 | 22.4 | 3/4 | 269.7 |
| 8 | 381 | 41.1 | 269.7 | 260.4 | 62 | 50.8 | 222.3 | 12 | 25.4 | 7/8 | 330.2 |
| 10 | 444.5 | 47.8 | 323.9 | 320.5 | 66.5 | 55.6 | 276.4 | 16 | 28.4 | 1 | 387.4 |
| 12 | 520.7 | 50.8 | 381 | 374.7 | 73.2 | 60.5 | 328.7 | 16 | 31.8 | 1-1/8 | 450.9 |
| 14 | 584.2 | 53.8 | 412.8 | 425.5 | 76.2 | 63.5 | 360.4 | 20 | 31.8 | 1-1/8 | 514.4 |
| 16 | 647.7 | 57.2 | 469.9 | 482.6 | 82.6 | 68.3 | 411.2 | 20 | 35.1 | 1-1/4 | 571.5 |
| 18 | 711.2 | 60.5 | 533.4 | 533.4 | 88.9 | 69.9 | 462 | 24 | 35.1 | 1-1/4 | 628.7 |
| 20 | 774.7 | 63.5 | 584.2 | 587.2 | 95.3 | 73.2 | 512.8 | 24 | 35.1 | 1-1/4 | 685.8 |
| 24 | 914.4 | 69.9 | 692.2 | 701.5 | 106.4 | 82.6 | 614.4 | 24 | 41.1 | 1-1/2 | 812.8 |
ANSI/ASME B16.5 Class 600 Threaded Flange – Dimensions & Sizes in mm
| Nominal Pipe Size |
Outside Dia of Flange (D) |
Thick of Flange (B) |
Dia of Raised Face (G) |
Dia of Hub at Base (A) |
Length thru Hub (H) |
Min Thread Length (T) |
Min Counter Bore (Q) |
No of Holes |
Dia of Holes (L) |
Dia of Bolts (inch) |
Dia of Bolt Circle (K) |
|---|---|---|---|---|---|---|---|---|---|---|---|
| 1/2 | 95.3 | 14.2 | 35.1 | 38.1 | 22.4 | 15.7 | 23.6 | 4 | 15.7 | 1/2 | 66.5 |
| 3/4 | 117.3 | 15.7 | 42.9 | 47.8 | 25.4 | 15.7 | 29 | 4 | 19.1 | 5/8 | 82.6 |
| 1 | 124 | 17.5 | 50.8 | 53.8 | 26.9 | 17.5 | 35.8 | 4 | 19.1 | 5/8 | 88.9 |
| 1-1/4 | 133.4 | 20.6 | 63.5 | 63.5 | 28.4 | 20.6 | 44.5 | 4 | 19.1 | 5/8 | 98.6 |
| 1-1/2 | 155.4 | 22.4 | 73.2 | 69.9 | 31.8 | 22.4 | 50.5 | 4 | 22.4 | 3/4 | 114.3 |
| 2 | 165.1 | 25.4 | 91.9 | 84.1 | 36.6 | 28.4 | 63.5 | 8 | 19.1 | 5/8 | 127 |
| 2-1/2 | 190.5 | 28.4 | 104.6 | 100.1 | 41.1 | 31.8 | 76.2 | 8 | 22.4 | 3/4 | 149.4 |
| 3 | 209.6 | 31.8 | 127 | 117.3 | 46 | 35.1 | 92.2 | 8 | 22.4 | 3/4 | 168.1 |
| 3-1/2 | 228.6 | 35.1 | 139.7 | 133.4 | 49.3 | 39.6 | 104.9 | 8 | 25.4 | 7/8 | 184.2 |
| 4 | 273.1 | 38.1 | 157.2 | 152.4 | 53.8 | 41.1 | 117.6 | 8 | 25.4 | 7/8 | 215.9 |
| 5 | 330.2 | 44.5 | 185.7 | 189 | 60.5 | 47.8 | 144.5 | 8 | 28.4 | 1 | 266.7 |
| 6 | 355.6 | 47.8 | 215.9 | 222.3 | 66.5 | 50.8 | 171.5 | 12 | 28.4 | 1 | 292.1 |
| 8 | 419.1 | 55.6 | 269.7 | 273.1 | 76.2 | 57.2 | 222.3 | 12 | 31.8 | 1-1/8 | 349.3 |
| 10 | 508 | 63.5 | 323.9 | 342.9 | 85.9 | 65 | 276.4 | 16 | 35.1 | 1-1/4 | 431.8 |
| 12 | 558.8 | 66.5 | 381 | 400.1 | 91.9 | 69.9 | 328.7 | 20 | 35.1 | 1-1/4 | 489 |
| 14 | 603.3 | 69.9 | 412.8 | 431.8 | 93.7 | 2.9 | 360.4 | 20 | 38.1 | 1-3/8 | 527.1 |
| 16 | 685.8 | 76.2 | 469.9 | 495.3 | 106.4 | 77.7 | 411.2 | 20 | 41.1 | 1-1/2 | 603.3 |
| 18 | 743 | 82.6 | 533.4 | 546.1 | 117.3 | 79.2 | 462 | 20 | 44.5 | 1-5/8 | 654.1 |
| 20 | 812.8 | 88.9 | 584.2 | 609.6 | 127 | 82.6 | 512.8 | 24 | 44.5 | 1-5/8 | 723.9 |
| 24 | 939.8 | 101.6 | 692.2 | 717.6 | 139.7 | 91.9 | 614.4 | 24 | 50.8 | 1-7/8 | 838.2 |
ANSI/ASME B16.5 Class 900 Threaded Flange – Dimensions & Sizes in mm
| Nominal Pipe Size |
Outside Dia of Flange (D) |
Thick of Flange (B) |
Dia of Raised Face (G) |
Dia of Hub at Base (A) |
Length thru Hub (H) |
Min Thread Length (T) |
Min Counter Bore (Q) |
No of Holes |
Dia of Holes (L) |
Dia of Bolts (inch) |
Dia of Bolt Circle (K) |
|---|---|---|---|---|---|---|---|---|---|---|---|
| 1/2 | 120.7 | 22.4 | 35.1 | 38.1 | 31.8 | 22.4 | 23.6 | 4 | 22.4 | 3/4 | 82.6 |
| 3/4 | 130 | 25.4 | 42.9 | 44.5 | 35.1 | 25.4 | 29 | 4 | 22.4 | 3/4 | 88.9 |
| 1 | 149.4 | 28.4 | 50.8 | 52.3 | 41.1 | 28.4 | 35.8 | 4 | 25.4 | 7/8 | 101.6 |
| 1-1/4 | 158.8 | 28.4 | 63.5 | 63.5 | 41.1 | 30.2 | 44.5 | 4 | 25.4 | 7/8 | 111.3 |
| 1-1/2 | 177.8 | 31.8 | 73.2 | 69.9 | 44.5 | 31.8 | 50.5 | 4 | 28.4 | 1 | 124 |
| 2 | 215.9 | 38.1 | 91.9 | 104.6 | 57.2 | 38.1 | 63.5 | 8 | 25.4 | 7/8 | 165.1 |
| 2-1/2 | 244.3 | 41.1 | 104.6 | 124 | 63.5 | 47.8 | 76.2 | 8 | 28.4 | 1 | 190.5 |
| 3 | 241.3 | 38.1 | 127 | 127 | 53.8 | 41.1 | 92.2 | 8 | 25.4 | 7/8 | 190.5 |
| 4 | 292.1 | 44.5 | 157.2 | 158.8 | 69.9 | 47.8 | 117.6 | 8 | 31.8 | 1-1/8 | 235 |
| 5 | 349.3 | 50.8 | 185.7 | 190.5 | 79.2 | 53.8 | 144.5 | 8 | 35.1 | 1-1/4 | 279.4 |
| 6 | 381 | 55.6 | 215.9 | 235 | 85.9 | 57.2 | 171.5 | 12 | 31.8 | 1-1/8 | 317.5 |
| 8 | 469.9 | 63.5 | 269.7 | 298.5 | 101.6 | 63.5 | 222.3 | 12 | 38.1 | 1-3/8 | 393.7 |
| 10 | 546.1 | 69.9 | 323.9 | 368.3 | 108 | 71.4 | 276.4 | 16 | 38.1 | 1-3/8 | 469.9 |
| 12 | 609.6 | 79.2 | 381 | 419.1 | 117.3 | 76.2 | 328.7 | 20 | 38.1 | 1-3/8 | 533.4 |
| 14 | 641.4 | 85.9 | 412.8 | 450.9 | 130 | 82.6 | 360.4 | 20 | 41.1 | 1-1/2 | 558.8 |
| 16 | 704.9 | 88.9 | 469.9 | 508 | 133.4 | 85.9 | 411.2 | 20 | 44.5 | 1-5/8 | 616 |
| 18 | 787.4 | 101.6 | 533.4 | 565.2 | 152.4 | 88.9 | 462 | 20 | 50.8 | 1-7/8 | 685.8 |
| 20 | 857.3 | 108 | 584.2 | 622.3 | 158.8 | 91.9 | 512.8 | 20 | 53.8 | 2 | 749.3 |
| 24 | 1041.4 | 139.7 | 692.2 | 749.3 | 203.2 | 101.6 | 614.4 | 20 | 66.5 | 2-1/2 | 901.7 |
ANSI/ASME B16.5 Class 1500 Threaded Flange – Dimensions & Sizes in mm
| Nominal Pipe Size |
Outside Dia of Flange (D) |
Thick of Flange (B) |
Dia of Raised Face (G) |
Dia of Hub at Base (A) |
Length thru Hub (H) |
Min Thread Length (T) |
Min Counter Bore (Q) |
No of Holes |
Dia of Holes (L) |
Dia of Bolts (inch) |
Dia of Bolt Circle (K) |
|---|---|---|---|---|---|---|---|---|---|---|---|
| 1/2 | 120.7 | 22.4 | 35.1 | 38.1 | 31.8 | 22.4 | 23.6 | 4 | 22.4 | 3/4 | 82.6 |
| 3/4 | 130 | 25.4 | 42.9 | 44.5 | 35.1 | 25.4 | 29 | 4 | 22.4 | 3/4 | 88.9 |
| 1 | 149.4 | 28.4 | 50.8 | 52.3 | 41.1 | 28.4 | 35.8 | 4 | 25.4 | 7/8 | 101.6 |
| 1-1/4 | 158.8 | 28.4 | 63.5 | 63.5 | 41.1 | 30.2 | 44.5 | 4 | 25.4 | 7/8 | 111.3 |
| 1-1/2 | 177.8 | 31.8 | 73.2 | 69.9 | 44.5 | 31.8 | 50.5 | 4 | 28.4 | 1 | 124 |
| 2 | 215.9 | 38.1 | 91.9 | 104.6 | 57.2 | 38.1 | 63.5 | 8 | 25.4 | 7/8 | 165.1 |
| 2-1/2 | 244.3 | 41.1 | 104.6 | 124 | 63.5 | 47.8 | 76.2 | 8 | 28.4 | 1 | 190.5 |
ANSI/ASME B16.5 Class 2500 Threaded Flange – Dimensions & Sizes in mm
| Nominal Pipe Size |
Outside Dia of Flange (D) |
Thick of Flange (B) |
Dia of Raised Face (G) |
Dia of Hub at Base (A) |
Length thru Hub (H) |
Min Thread Length (T) |
Min Counter Bore (Q) |
No of Holes |
Dia of Holes (L) |
Dia of Bolts (inch) |
Dia of Bolt Circle (K) |
|---|---|---|---|---|---|---|---|---|---|---|---|
| 1/2 | 133.4 | 30.2 | 35.1 | 42.9 | 39.6 | 28.4 | 23.6 | 4 | 22.4 | 3/4 | 88.9 |
| 3/4 | 139.7 | 31.8 | 42.9 | 50.8 | 42.9 | 31.8 | 29 | 4 | 22.4 | 3/4 | 95.3 |
| 1 | 158.8 | 35.1 | 50.8 | 57.2 | 47.8 | 35.1 | 35.8 | 4 | 25.4 | 7/8 | 108 |
| 1-1/4 | 184.2 | 38.1 | 63.5 | 73.2 | 52.3 | 38.1 | 44.5 | 4 | 28.4 | 1 | 130 |
| 1-1/2 | 203.2 | 44.5 | 73.2 | 79.2 | 60.5 | 44.5 | 50.5 | 4 | 31.8 | 1-1/8 | 146.1 |
| 2 | 235 | 50.8 | 91.9 | 95.3 | 69.9 | 50.8 | 63.5 | 8 | 28.4 | 1 | 171.5 |
| 2-1/2 | 266.7 | 57.2 | 104.6 | 114.3 | 79.2 | 57.2 | 76.2 | 8 | 31.8 | 1-1/8 | 196.9 |
Threaded Piping Flange Weight Chart (lbs) – Pressure Class 150 to 2500
| NPS (inches) | Class 150 | Class 300 | Class 600 | Class 900 | Class 1500 | Class 2500 |
|---|---|---|---|---|---|---|
| ½ | 1.2 lbs | 2.1 lbs | 3.4 lbs | 5.0 lbs | 7.8 lbs | 12.0 lbs |
| ¾ | 1.5 lbs | 2.6 lbs | 4.0 lbs | 6.2 lbs | 9.5 lbs | 14.8 lbs |
| 1 | 1.9 lbs | 3.1 lbs | 5.0 lbs | 7.6 lbs | 11.8 lbs | 18.5 lbs |
| 1 ½ | 3.2 lbs | 5.8 lbs | 9.0 lbs | 13.4 lbs | 20.9 lbs | 32.0 lbs |
| 2 | 4.5 lbs | 8.0 lbs | 12.5 lbs | 18.8 lbs | 29.5 lbs | 45.0 lbs |
| 3 | 7.8 lbs | 13.5 lbs | 21.2 lbs | 31.5 lbs | 49.0 lbs | 74.8 lbs |
| 4 | 11.5 lbs | 20.5 lbs | 32.4 lbs | 48.2 lbs | 74.8 lbs | 114.0 lbs |
| 6 | 20.5 lbs | 36.5 lbs | 58.0 lbs | 86.5 lbs | 134.0 lbs | 205.0 lbs |
| 8 | 32.5 lbs | 58.0 lbs | 92.0 lbs | 138.0 lbs | 214.0 lbs | 325.0 lbs |
| 10 | 50.0 lbs | 89.0 lbs | 141.0 lbs | 212.0 lbs | 328.0 lbs | 500.0 lbs |
| 12 | 65.0 lbs | 118.0 lbs | 188.0 lbs | 282.0 lbs | 436.0 lbs | 665.0 lbs |
| 14 | 82.0 lbs | 150.0 lbs | 240.0 lbs | 360.0 lbs | 556.0 lbs | 840.0 lbs |
| 16 | 105.0 lbs | 192.0 lbs | 307.0 lbs | 462.0 lbs | 720.0 lbs | 1085.0 lbs |
| 18 | 128.0 lbs | 234.0 lbs | 374.0 lbs | 562.0 lbs | 876.0 lbs | 1320.0 lbs |
| 20 | 155.0 lbs | 280.0 lbs | 450.0 lbs | 675.0 lbs | 1055.0 lbs | 1590.0 lbs |
| 24 | 210.0 lbs | 380.0 lbs | 610.0 lbs | 915.0 lbs | 1425.0 lbs | 2150.0 lbs |
THRF Flange Tolerances as per ANSI / ASME B16.5, 16.47
| Parameter | Tolerance (mm) | Notes |
|---|---|---|
| Outside Diameter of Flange (OD) | ±1.5 mm (Up to 24″)±3.0 mm (Above 24″) | Maintains uniform bolt alignment. |
| Bolt Circle Diameter (BCD) | ±1.5 mm | Ensures accurate bolt hole positioning. |
| Bolt Hole Diameter | +1.5 mm / 0 mm | No minus tolerance allowed for proper bolt fit. |
| Bolt Hole Center-to-Center | ±1.0 mm | For equal load distribution. |
| Flange Thickness | ±1.5 mm (Up to 24″)±2.0 mm (Above 24″) | Critical for pressure rating compliance. |
| Raised Face Height | ±0.5 mm | Important for gasket seating surface. |
| Thread Bore (NPT / BSP) | As per ASME B1.20.1 or ISO 7/1 | Must comply with pipe thread standards. |
| Hub Diameter | ±1.5 mm | Ensures smooth fit with pipe OD. |
| Facing Finish (Ra) | 3.2–6.3 μm (125–250 AARH) | Required for gasket sealing surface. |
| Concentricity of Bore to OD | ≤1.5 mm | Prevents misalignment during installation. |
| Perpendicularity of Flange Face to Bore | ≤1.0 mm per 25 mm | Ensures proper gasket compression. |
What are the advantages of using a Threaded Flange?
-
No Welding Required – eliminates welding cost and skilled labor.
-
Time Saving – quick installation and dismantling.
-
Ideal for Hazardous Areas – avoids sparks from welding.
-
Cost Effective for Small Sizes – particularly for pipe diameters under 2”.
-
Reusability – can be removed and reused in other systems.
-
Compatible with Various Materials – available in carbon steel, stainless steel, duplex, and high nickel alloys.
How to ensure leak-proof sealing in Threaded Flanges?
-
Use thread sealants or PTFE tapes on male threads.
-
Apply proper torque to avoid over-tightening (which may crack the flange).
-
In some designs, a seal weld is added after threading for extra safety.
-
Ensure machined faces (RF or RTJ) are within ASME tolerance for gasket seating.
-
Select compatible gasket material based on temperature, pressure, and media.
What types of faces are available for Threaded Flanges?
-
Raised Face (RF) – standard for most applications.
-
Flat Face (FF) – used in cast iron or non-metallic piping.
-
Ring Type Joint (RTJ) – for high-pressure and leak-proof sealing.