FAISAL Steel, located in Muscat, Oman, stands out as a top manufacturer and supplier of premium steel products, with a special focus on Low Temperature Carbon Steel LF1 Flanges. Known for their precision in manufacturing and commitment to quality, FAISAL Steel produces flanges that are built to last, ensuring reliability and safety. LF1 flanges are specifically engineered to handle extremely low temperatures, making them perfect for critical applications in the oil, gas, and chemical sectors. Thanks to advanced production methods and thorough quality checks, FAISAL Steel guarantees that each LF1 flange adheres to international standards, offering trustworthy solutions for pipelines, industrial systems, and construction projects.
These LF1 flanges are primarily made up of carbon, manganese, phosphorus, sulfur, and a few trace elements, all carefully balanced to ensure toughness even in sub-zero conditions. They boast impressive impact resistance and high tensile strength, typically featuring a yield strength of around 250–310 MPa and an ultimate tensile strength ranging from 410–550 MPa. Even in low-temperature settings, LF1 flanges maintain their ductility and elongation, which helps reduce the risk of brittle fractures. Their meticulously controlled chemical makeup and outstanding mechanical properties guarantee reliable performance in cold-service pipelines, cryogenic systems, and various low-temperature industrial applications.
| Element | Weight % |
| Carbon | 0.08 – 0.15 |
| Silicon | 0.15 – 0.50 |
| Manganese | 0.30 – 0.60 |
| Phosphorus | 0.025 max * |
| Sulfur | 0.025 max * |
| Molybdenum | 0.90 – 1.10 |
| Chromium | 2.00 – 2.50 |
| Nickel | 0.5 max |
| Property | Values |
| Ultimate Tensile Strength * | 95 min Ksi (655 Mpa) |
| 0.2 % Yield Strength * | 75 min Ksi (517 Mpa) |
| Elongation * | 17 % min |
| Reduction of Area * | 35 % min |
| Charpy Impact Toughness | 42 mean/ 33 min J at –18o C |
| Hardness | 197 – 237 BHN (75 Ksi min) |
We provide products that come with both mill test certificates and third-party test certificates, ensuring the highest standards of quality and compliance.
FAISAL Steel is one of the most prominent manufacturers and suppliers of superior quality Low Temperature Carbon Steel LF1 Flanges in Muscat, OMAN. As experts in steel solutions, we supply a complete spectrum of products like Carbon Steel, Alloy Steel, Mild Steel, and Galvanized Steel. Our product range comprises Pipes, Tubes, Flanges, Pipe Fittings, Forged Fittings, Sheets, and Plates. Known for our reliable delivery and first-rate customer service, we are committed to supplying high-quality steel materials that guarantee durability and excellent performance in numerous industrial applications.Â
| TEMP °C | Class 150 | Class 300 | Class 400 | Class 600 | Class 900 | Class 1500 | Class 2500 |
| -29 TO 38 | 19.6 | 51.1 | 68.1 | 102.1 | 153.2 | 255.3 | 425.5 |
| 50 | 19.2 | 50.1 | 66.8 | 100.2 | 150.4 | 250.6 | 417.7 |
| 100 | 17.7 | 46.6 | 62.1 | 93.2 | 139.8 | 233 | 388.3 |
| 150 | 15.8 | 45.1 | 60.1 | 90.2 | 135.2 | 225.4 | 375.6 |
| 200 | 13.8 | 43.8 | 58.4 | 87.6 | 131.4 | 219 | 365 |
| 250 | 12.1 | 41.9 | 55.9 | 83.9 | 125.8 | 209.7 | 349.5 |
| 300 | 10.2 | 39.8 | 53.1 | 79.6 | 119.5 | 199.1 | 331.8 |
| 325 | 9.3 | 38.7 | 51.6 | 77.4 | 116.1 | 193.6 | 322.6 |
| 350 | 8.4 | 37.6 | 50.1 | 75.1 | 112.7 | 187.8 | 313 |
| 375 | 7.4 | 36.4 | 48.5 | 72.7 | 109.1 | 181.8 | 303.1 |
| 400 | 6.5 | 34.7 | 46.3 | 69.4 | 104.2 | 173.6 | 289.3 |
| 425 | 5.5 | 28.8 | 38.4 | 57.5 | 86.3 | 143.8 | 239.7 |
| 450 | 4.6 | 23 | 30.7 | 46 | 69 | 115 | 191.7 |
| 475 | 3.7 | 17.4 | 23.2 | 34.9 | 52.3 | 87.2 | 145.3 |
| 500 | 2.8 | 11.8 | 15.7 | 23.5 | 35.3 | 58.8 | 97.9 |
| 538 | 1.4 | 5.9 | 7.9 | 11.8 | 17.7 | 29.5 | 49.2 |
| NPS | O.D. of Flange | Flanges Thickness | Diameter of RF | Diameter of Hub at Base | Lengtd Tdru Hub | Bore or Diameter | Dia. of Hub at Bevel | Radius of Fillet | Deptd of Socket | |||
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Welding (WN) Neck | Slip-On (SORF) Threaded (NPT) Socket (SWRF) | Lap Joint (Loose) | Slip-on (SORF) Socket (SWRF) | Lap Joint (Loose) | ||||||||
| O | Q | R | X | Y | Y | Y | W | B | H | r | Z | |
| 1/2 | 3-1/2 | 7/16 | 1-3/8 | 1-3/16 | 1-7/8 | 5/8 | 5/8 | .88 | .90 | .84 | 1/8 | 3/8 |
| 3/4 | 3-7/8 | 1/2 | 1-11/16 | 1-1/2 | 2-1/16 | 5/8 | 5/8 | 1.09 | 1.11 | 1.05 | 1/8 | 7/16 |
| 1 | 4-1/4 | 9/16 | 2 | 1-15/16 | 2-3/16 | 11/16 | 11/16 | 1.36 | 1.38 | 1.32 | 1/8 | 1/2 |
| 1-1/4 | 4-5/8 | 5/8 | 2-1/2 | 2-5/16 | 2-1/4 | 13/16 | 13/16 | 1.70 | 1.72 | 1.66 | 3/16 | 9/16 |
| 1-1/2 | 5 | 11/16 | 2-7/8 | 2-9/16 | 2-7/16 | 7/8 | 7/8 | 1.95 | 1.97 | 1.90 | 1/4 | 5/8 |
| 2 | 6 | 3/4 | 3-5/8 | 3-1/16 | 2-1/2 | 1 | 1 | 2.44 | 2.46 | 2.38 | 5/16 | 11/16 |
| 2-1/2 | 7 | 7/8 | 4-1/8 | 3-9/16 | 2-3/4 | 1-1/8 | 1-1/8 | 2.94 | 2.97 | 2.88 | 5/16 | 3/4 |
| 3 | 7-1/2 | 15/16 | 5 | 4-1/4 | 2-3/4 | 1-3/16 | 1-3/16 | 3.57 | 3.60 | 3.50 | 3/8 | 13/16 |
| 3-1/2 | 8-1/2 | 15/16 | 5-1/2 | 4-13/16 | 2-13/16 | 1-1/4 | 1-1/4 | 4.07 | 4.10 | 4.00 | 3/8 | 7/8 |
| 4 | 9 | 15/16 | 6-3/16 | 5-5/16 | 3 | 1-5/16 | 1-5/16 | 4.57 | 4.60 | 4.50 | 7/16 | 15/16 |
| 5 | 10 | 15/16 | 7.5/16 | 6-7/16 | 3-1/2 | 1-7/16 | 1-7/16 | 5.66 | 5.69 | 5.56 | 7/16 | 15/16 |
| 6 | 11 | 1 | 8-1/2 | 7-9/16 | 3-1/2 | 1-9/16 | 1-9/16 | 6.72 | 6.75 | 6.63 | 1/2 | 1-1/16 |
| 8 | 13-1/2 | 1-1/8 | 10-5/8 | 9-11/16 | 4 | 1-3/4 | 1-3/4 | 8.72 | 8.75 | 8.63 | 1/2 | 1-1/4 |
| 10 | 16 | 1-3/16 | 12-3/4 | 12 | 4 | 1-15/16 | 1-15/16 | 10.88 | 10.92 | 10.75 | 1/2 | 1-5/16 |
| 12 | 19 | 1-1/4 | 15 | 14-3/8 | 4-1/2 | 2-3/16 | 2-3/16 | 12.88 | 12.92 | 12.75 | 1/2 | 1-9/16 |
| 14 | 21 | 1-3/8 | 16-1/4 | 15-3/4 | 5 | 2-1/4 | 3-1/8 | 14.14 | 14.18 | 14.00 | 1/2 | 1-5/8 |
| 16 | 23-1/2 | 1-7/16 | 18-1/2 | 18 | 5 | 2-1/2 | 3-7/16 | 16.16 | 16.19 | 16.00 | 1/2 | 1-3/4 |
| 18 | 25 | 1-9/16 | 21 | 19-7/8 | 5-1/2 | 2-11/16 | 3-13/16 | 18.18 | 18.lf2 | 18.00 | 1/2 | 1-15/16 |
| lf2 | 27-1/2 | 1-11/16 | 23 | 22 | 5-11/16 | 2-7/8 | 4-1/16 | lf2.lf2 | lf2.25 | lf2.00 | 1/2 | 2-1/8 |
| 24 | 32 | 1-7/8 | 27-1/4 | 26-1/8 | 6 | 3-1/4 | 4-3/8 | 24.25 | 24.25 | 24.00 | 1/2 | 2-1/2 |
| Nominal Pipe Sizes (NPS) | Slip On (SORF) | Threaded (NPT) | Socket Weld (SWRF) | Lap Joint (Loose) | Blind (BLRF) | Weld Neck (WRNR) |
|---|---|---|---|---|---|---|
| ½ | 1 | 1 | 2 | 1 | 2 | 2 |
| ¾ | 2 | 2 | 2 | 2 | 2 | 2 |
| 1 | 2 | 2 | 2 | 2 | 2 | 3 |
| 1¼ | 3 | 3 | 3 | 3 | 3 | 3 |
| 1½ | 3 | 3 | 3 | 3 | 4 | 4 |
| 2 | 5 | 5 | 5 | 5 | 5 | 6 |
| 2½ | 8 | 8 | 8 | 8 | 7 | 10 |
| 3 | 9 | 9 | 9 | 9 | 9 | 11.5 |
| 3½ | 11 | 12 | 11 | 11 | 13 | 12 |
| 4 | 13 | 13 | 13 | 13 | 17 | 16.5 |
| 5 | 15 | 15 | 15 | 15 | lf2 | 21 |
| 6 | 19 | 19 | 19 | 19 | 27 | 26 |
| 8 | 30 | 30 | 30 | 30 | 47 | 42 |
| 10 | 43 | 43 | 43 | 43 | 70 | 54 |
| 12 | 64 | 64 | 64 | 64 | 123 | 88 |
| 14 | 90 | 90 | 90 | 105 | 140 | 114 |
| 16 | 106 | 98 | 98 | 140 | 180 | 140 |
| 18 | 130 | 130 | 130 | 160 | 2lf2 | 165 |
| lf2 | 165 | 165 | 165 | 195 | 285 | 197 |
| 22 | 185 | 185 | 185 | 245 | 355 | 225 |
| 24 | 2lf2 | 2lf2 | 2lf2 | 275 | 430 | 268 |
LF1 flanges find extensive use in industries where performance in freezing conditions is essential. They’re commonly utilized in oil and gas pipelines, chemical processing facilities, LNG terminals, and cryogenic storage systems. These flanges create secure connections between pipes, valves, and equipment, ensuring leak-proof and durable operation even in harsh environments. LF1 flanges are designed to resist brittle fractures and thermal contraction, making them ideal for petrochemical plants, refrigeration systems, and industrial setups that face extreme cold. Engineers trust LF1 flanges for their reliability and performance in demanding conditions.
FAISAL Steel is a leading manufacturer, supplier and exporter of high-quality Carbon Steel, Alloy Steel, Mild Steel and Galvanized Steel products. Our extensive product range includes Pipes, Tubes, Flanges, Pipe Fittings, Forged Fittings, Sheets and Plates, catering to various industries in Muscat, OMAN.
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