Yousef Steel, a well-respected steel manufacturer and supplier located in Riyadh, Saudi Arabia, specializes in high-performance flange solutions designed for challenging low-temperature applications. One of their standout products is the **Low Temperature Carbon Steel LF3 flanges**, crafted in accordance with ASTM A350 standards. These flanges are engineered to uphold structural integrity and toughness even in cryogenic and sub-zero conditions. LF3 flanges find their place in various industries, including LNG, petrochemicals, oil and gas, and refrigeration, where dependable performance under thermal stress is essential. Yousef Steel prides itself on rigorous quality control, precise manufacturing, and timely delivery for every order.
The ASTM A350 LF3 is a low-temperature carbon steel alloy that incorporates nickel to boost notch toughness and impact resistance. Its typical chemical makeup includes carbon (max 0.20%), manganese (0.60–1.35%), phosphorus (max 0.035%), sulfur (max 0.040%), and nickel (0.40–1.00%), which collectively enhance its mechanical properties compared to LF2. LF3 flanges boast a minimum yield strength of 240 MPa and a minimum tensile strength of 485 MPa. They undergo impact testing at temperatures as low as -101°C (-150°F), making them perfect for deep cryogenic applications. Additionally, they offer excellent weldability and corrosion resistance in cold environments.
| Material Specification Of : | ASTM A350 LF3 Flanges |
|---|---|
| Pressure Rating | Class 150 To Class 2500 |
| High Temperature | Above 200°C (400°F) For Class 150 Or Above 400°C (750°F) |
| Low Temperature | Above -29 Degree C (−20°F) |
| Russian-Standard Flanges | GOST 12820 / 12821-80, DIN, UNI, EN 1092-1 |
| South African Standard Flanges | SANSflanges And SABS flanges |
| Surface Finish | smooth, concentric serrated, stock |
| Gaskets Types | Full Face Gasket Flat Ring Gasket Metallic Ring Gakset |
| Advantages Of Pipe Flange | Used to Connect Pipe System Easy Repair Pipe System Assembled Without Welding |
| Common Types Of Flanges: | Slip On (SORF), Weld Neck (WNRF), Blind (BLRF), Lap Joint (Loose), Threaded (NPT), Socket-Weld (SWRF) |
| Special Types Of Flanges : | Nipoflange, Elboflange, Latroflange, Swivel Flange, Expanding Flange, Reducing Flange, Weldoflange |
| Marking Standard | Name of Manufacturer Schedule Type of Flange Facing Nominal Pipe Size Pressure Class ASME B16 Designation |
| Standard Cover : | pressure ratings & temperature ratings, materials, marking, dimensions, weight, tolerances, testing |
| Contact Faces | RTJ (Ring Type Joint), FF (Flat Face), RF (Raised Face), T/G (Tongue And Groove ), M/F (Male And Female) |
| Size Chart | Normal Pipe Size 1/2 to NPS 24″ |
| Thickness | Normal Pipe Size ≤ 18 |
| Bore Diameter | Normal Pipe ≤ 10 |
| Flanges Standards | EN 1092-1, JIS, ASME B16.5, ASME B16.47 type A, UNI, DIN |
| Bolt Type | high strength bolts medium strength bolts low strength bolts |
| European Standard Flanges | JIS B2220 Flanges (5k to 30k) and KS1503 flanges |
| Element | Composition |
|---|---|
| Carbon, maximum | 0.20 maximum |
| Manganese | 0.90 maximum |
| Phosphorus, maximum | 0.035 maximum |
| Sulfur, maximum | 0.040 maximum |
| Silicon [Note A] | 0.20–0.35 |
| Nickel | 3.3–3.7 |
| Chromium | 0.30 maximum [Note C] |
| Molybdenum | 0.12 maximum [Note C] |
| Copper | 0.40 maximum |
| Columbium | 0.02 maximum |
| Vanadium | 0.03 maximum |
Tensile Strength, minimum: | 70,000 psi (485 MPa] |
Minimum. Yield Point: | 36,000 psi [250 MPa] |
Reduction of area, minimum: | 30% minimum |
Hardness, HB, maximum | 187 |
We provide products that come with both mill test certificates and third-party test certificates, ensuring the highest standards of quality and compliance.
Low Temperature Carbon Steel LF3 flanges are frequently utilized in piping systems that transport liquefied gases, chilled fluids, and hydrocarbons under extreme cold conditions. Their applications span LNG storage tanks, cryogenic processing units, heat exchangers, and offshore platforms. Available in various styles—such as weld neck, blind, slip-on, and threaded—LF3 flanges ensure reliable sealing, structural strength, and long-lasting durability. With their superior low-temperature performance and nickel-enhanced composition, LF3 flanges are a top choice for demanding environments.
| 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 |
| TEMP °C | 150 | 300 | 400 | 600 | 900 | 1500 | 2500 |
| 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 |
Carbon steel LF3 flanges are widely used in low temperature applications due to their excellent cruelty and durability. They are usually used in industries such as oil and gas, petrochemicals, power plants and cryogenic systems. These flanges ensure safe pipe connections in a very cold environment, prevent leaks and increase the efficiency of the system. LF3 flanges are also used in pressure vessels, heat exchange and refineries, which provide high strength, corrosion resistance and weldability. Their reliability is necessary for their low temperature fluids and pipelines that handle gases.
Yousef 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 Riyadh, Saudi Arabia.
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