Yousef Steel, a prominent steel manufacturer and supplier located in Riyadh, Saudi Arabia, provides an extensive selection of specialized piping components designed for cold-service environments. Among their top-notch products are the **Low Temperature Carbon Steel LF5 flanges**, crafted in line with ASTM A350 standards. These flanges are specifically engineered for cryogenic and low-temperature applications, where high toughness, strength, and thermal stability are crucial. LF5 flanges find their place in industries such as LNG, petrochemical, oil and gas, and offshore sectors, where reliability in extreme conditions is a must. Yousef Steel guarantees meticulous production, rigorous testing, and prompt delivery to meet all project requirements.
ASTM A350 LF5 is a low-temperature carbon steel alloy that includes elements like nickel, chromium, and molybdenum to enhance impact resistance, corrosion resistance, and strength in low-temperature settings. Its typical chemical makeup features carbon (max 0.13%), manganese (0.60–1.35%), phosphorus (max 0.035%), sulfur (max 0.040%), nickel (2.03–2.57%), chromium (0.44–0.86%), and molybdenum (0.44–0.65%). LF5 flanges undergo impact performance testing at temperatures as low as -73°C (-100°F), ensuring exceptional mechanical reliability in cold environments. This grade also boasts a minimum yield strength of 275 MPa and a tensile strength of 485 MPa, making it durable in high-stress situations.
Element | Composition, w.t % Grades |
 | LF5 |
C | ≤0.30 |
Mn | 0.60-1.35 |
P | ≤0.035 |
S | ≤0.040 |
Si | 0.20-0.35 |
Ni | 1.00-2.00 |
Cr | ≤0.30 |
Mo | ≤0.12 |
Cu | ≤0.40 |
Cb | ≤0.02 |
|
Grade/Class |
Tensile Strength |
Yield Strength, min. |
Elongation, min. |
Hardness, max. |
||
|
LF5 |
70–95 |
485–655 |
37.5 |
260 |
22 |
197 |
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 LF5 flanges are perfect for applications involving liquefied gases, cryogenic fluids, and low-temperature process streams. They are commonly utilized in LNG terminals, refrigerated storage systems, offshore platforms, and chemical plants where extreme cold and thermal cycling are prevalent. Available in standard types such as weld neck, blind, slip-on, socket weld, and threaded flanges, LF5 ensures secure connections with outstanding resistance to thermal stress.
| ASME/ANSI B 16.5 | LTCS A350 LF5Â Welding Neck Flange, LTCS A350 LF5Â Slip on Flange, Blind Flange, High Hub Blind Flange, Socket Weld Flange, LTCS A350 LF5Â Lap Joint Flange, Threaded Flange, LTCS A350 LF5Â Ring Type Joint Flange |
| PRESSURE CLASS | 150, 300, 400, 600, 900, 1500, 2500 |
| ASME/ANSI B 16.47 | LTCS A350 LF5Â Welding Neck Flange, LTCS A350 LF5Â Blind Flange [Series A & B] |
| PRESSURE CLASS | 75, 150, 300, 400, 600, 900 |
| ASME/ANSI B 16.36 | LTCS A350 LF5Â Welding Neck Flange, LTCS A350 LF5Â Slip on Flange, LTCS A350 LF5Â Threaded Flange |
| PRESSURE CLASS | 300, 400, 600, 900, 1500, 2500 |
| BS 4504 SEC 3.1 | LTCS A350 LF5Â Welding Neck Flange, LTCS A350 LF5Â Hubbed Slip on Flange, LTCS A350 LF5Â Hubbed Threaded Flange, Lapped Pipe End Flange, LTCS A350 LF5Â Plate Flange, Loose Plate Flange, Loose Plate With Weld Neck Flange, Blank Flange |
| PRESSURE CLASS | PN 2.5 TO PN 40 |
| BS 4504[PART 1] | LTCS A350 LF5Â Welding Neck Flange, LTCS A350 LF5Â Hubbed Slip-On Hubbed Threaded, Plate Flange, LTCS A350 LF5Â Loose Plate With Weld On Plate Collar, Blank Flange |
| PRESSURE CLASS | PN 2.5 TO PN 400 |
| BS 1560 BOSS | LTCS A350 LF5Â Welding Neck Flange, Socket Welding Flange, LTCS A350 LF5Â Slip-On Flange, LTCS A350 LF5Â Blind Flange, LTCS A350 LF5Â Screwed Boss Flange, LTCS A350 LF5Â Lapped Flange |
| PRESSURE CLASS | 150, 300, 400, 600, 900, 1500, 2500 |
| BS10 | LTCS A350 LF5Â Welding Neck Flange, LTCS A350 LF5Â Plate Slip-On Flange, LTCS A350 LF5Â Screwed Boss Flange, Slip-On Boss Flange, LTCS A350 LF5Â Blind Flange |
| TABLE | D, E, F, H |
| DIN FLANGES | DIN 2527, 2566, 2573, 2576, 2641,2642, 2655, 2656, 2627, 2628, 2629, 2631, 2632, 2633, 2634, 2635, 2636, 2637,2638, 2673 |
| PRESSURE CLASS | PN 6 TO PN 100 |
| 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 LF5 flanges are often used in industries that require strength, durability, and ability to handle cold temperatures. You can see them in oil and gas pipelines, petrochemical plants, power generation, and shipbuilding. They are also found in pressure vessels, heat exchangers, and refineries, where some strength and toughness count. LF5 flanges are easy to weld and resist rust, making them good for joining pipes in tough conditions. They help to keep things safe and last a long time.
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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