Yousef Steel, a prominent manufacturer and supplier located in Riyadh, Saudi Arabia, proudly presents a comprehensive selection of industrial flanges designed specifically for low-temperature applications. Among their standout offerings are the **Low Temperature Carbon Steel LF2 flanges**, which are essential for critical operations that demand toughness, strength, and durability in freezing conditions. These flanges are produced in accordance with ASTM A350 standards, making them ideal for sectors like oil and gas, LNG, petrochemicals, and offshore projects. Yousef Steel is committed to delivering top-notch quality, strictly following international standards, and ensuring a reliable supply for even the most challenging projects.
The ASTM A350 LF2 grade is a low-temperature carbon steel known for its impressive impact resistance and mechanical properties in cold environments. Its chemical makeup typically features carbon (max 0.30%), manganese (0.60–1.35%), phosphorus (max 0.035%), sulfur (max 0.040%), along with trace elements that improve ductility and weldability. LF2 flanges boast a minimum yield strength of 250 MPa and a minimum tensile strength of 485 MPa. These flanges are rigorously tested with Charpy V-notch impact assessments at temperatures as low as -46°C (-50°F), ensuring they can withstand thermal stress and pressure changes in cryogenic or cold-service systems.
| Specification | ASTM A350 / ASME SA350 |
|---|---|
| Size Chart | 1/2″ (15 NB) to 48″ (1lf20NB) DN10~DN5000 |
| Standards | ANSI/ASME B16.5, B16.47 Series A & B, B16.48, BS4504, BS 10, EN-1092, DIN, ANSI Flanges, ASME Flanges, BS Flanges, DIN Flanges, EN Flanges, GOST Flange, ASME/ANSI B16.5/16.36/16.47A/16.47B, MSS S44, ISO70051, JISB22lf2, BS1560-3.1, API7S-15, API7S-43, API605, EN1092 |
| Pressure Rating ANSI | Class 150 LBS, 300 LBS, lf2 LBS, 900 LBS, 1500 LBS, 2500 LBS |
| Pressure Calculation in DIN | 6Bar 10Bar 16Bar 25Bar 40Bar / PN6 PN10 PN16 PN25 PN40, PN64 |
| UNI | 6Bar 10Bar 16Bar 25Bar 40Bar |
| EN | 6Bar 10Bar 16Bar 25Bar 40Bar |
| Coating | Oil Black Paint, Anti-rust Paint, Zinc Plated, Yellow Transparent, Cold and Hot Dip Galvanized |
| Test Certificates | EN 10lf24/3.1B Raw Materials Certificate 100% Radiography Test Report Third Party Inspection Report, etc |
| Production Technique | Forged, Heat treated and machined |
| Connect Type/ Flange Face Type | Raised Face (RF), Ring Type Joint (RTJ), Flat Face (FF), Large Male-Female (LMF), Lap-Joint Face (LJF), Small Male-Female (SMF), Small Tongue, Large Tongue & Groove, Groove |
| Special design | As per your drawing AS, ANSI, BS, DIN and JIS 15 NB (1/2″) to lf20 NB (8″) Equal and Reducing Configurations |
| Test | Direct-reading Spectrograph, Hydrostatic testing machine, X-ray detector, UI trasonic flaw detector, Magnetic particle detector |
| Equipment | Press machine, Bending machine, Pushing Machine, electric bevelling machine, Sand-blasting machine etc |
| Manufacturer of | ANSI DIN, GOST, JIS, UNI, BS, AS2129, AWWA, EN, SABS, NFE etc. BS Flange, EN Flange, API 6A Flange, ANSI Flange, ASME Flange, DIN Flange, EN1092-1 Flange, UNI Flange, JIS/ KS Flange, BS4504 Flange, GB Flange, AWWA Clf27 Flange, GOST Flange, PSI Flange B.S: BS4504 , BS3293, BS1560, BS10 AS 2129: Table D; Table E; Table H ANSI B16.5, ANSI B16.47 Series A & B, MSS SP44, ASA, API-605, AWWA, Custom Drawings ANSI : ANSI B16.5, ANSI B16.47(API605), MSS SP44, ANSI B16.36, ANSI B16.48 ANSI B16.5, ANSI B16.47, MSS SP44, ANSI B16.36, ANSI B16.48 American standard (ANSI) German (DIN) British standard (BS) DIN: DIN 2527, DIN 2566, DIN 2573, DIN 2576, DIN 2641, DIN 2642, DIN 2655, DIN 2656, DIN 2627, DIN 2628, DIN 2629, DIN 2631, DIN 2632, DIN 2633, DIN 2634, DIN 2635, DIN 2636, DIN 2637, DIN 2638 The other standard: AWWA Clf27; EN1092-1, GOST128lf2, JIS B22lf2; KS B1503, SABS1123; NFE29lf23; UNI2276 |
| Grade | C | Si | Mn | P | S | Cr | Mo | Cu | Nb | V |
| A350 LF2 | ≤0.30% | 0.15 – 0.30% | 0.60 – 1.35% | ≤0.035% | ≤0.040% | ≤0.30 % | ≤0.12% | ≤0.40% | ≤0.02% | ≤0.08% |
| Grade | Tensile strength, (MPa) | Yield (0.2%) (MPa) | Elongation (%) | Reduction of Area (%) | Hardness HB |
| LTCS LF2 | 485-655(70-95KSi) | 250(36KSi) | 22 | 30 | ≤197HB |
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 LF2 flanges are frequently utilized in low-temperature piping systems for the transport of hydrocarbons, chilled fluids, and liquefied gases. They are perfect for flanged connections in pipelines, valves, heat exchangers, and pressure vessels, especially in cold climates and offshore settings. With a variety of types available—including weld neck, slip-on, blind, and socket weld—LF2 flanges ensure secure sealing, outstanding weldability, and resistance to corrosion in tough environments. Their robust performance and adherence to global standards make them a reliable choice for any demanding application.
| ASME/ANSI B 16.5 | Blind Flange, High Hub Blind Flange, Slip on Flange, Welding Neck Flange, Socket Weld Flange, Ring Type Joint Flange, Lap Joint Flange, Threaded Flange |
| PRESSURE CLASS | 150, 300, 400, lf2, 900, 1500, 2500 |
| ASME/ANSI B 16.47 | Blind Flange [Series A & B],Welding Neck Flange |
| PRESSURE CLASS | 75, 150, 300, 400, lf2, 900 |
| ASME/ANSI B 16.36 | Slip on Flange, Threaded Flange, Welding Neck Flange, |
| PRESSURE CLASS | 300, 400, lf2, 900, 1500, 2500 |
| BS 4504 SEC 3.1 | Plate Flange, Loose Plate Flange, Loose Plate With Weld Neck Flange, Blank Flange, Welding Neck Flange, Hubbed Slip on Flange, Hubbed Threaded Flange, Lapped Pipe End Flange, |
| PRESSURE CLASS | PN 2.5 TO PN 40 |
| BS 4504[PART 1] | Plate Flange, Loose Plate With Weld On Plate Collar, Blank Flange, Welding Neck Flange, Hubbed Slip-On Hubbed Threaded, |
| PRESSURE CLASS | PN 2.5 TO PN 400 |
| BS 1560 BOSS | Plate Flange, Loose Plate With Weld On Plate Collar, Blank Flange, Welding Neck Flange, Hubbed Slip-On Hubbed Threaded, |
| PRESSURE CLASS | 150, 300, 400, lf2, 900, 1500, 2500 |
| BS10 | Welding Neck Flange, Plate Slip-On Flange, Screwed Boss Flange, Slip-On Boss Flange, 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 |
Low Temperature Carbon Steel LF2 Flanges are widely used in industries that need high strength and durability in very cold temperatures. They are important in oil & gas, petrochemicals, power generation, and cryogenic industries. These flanges help make leak-proof seals in pipelines, valves, and pressure vessels. They have high toughness, are easy to weld, and resist corrosion. This makes them good for transporting liquid natural gas (LNG), working in refineries, and offshore drilling. They work well in low temperatures, ensuring safe fluid flow and reducing the risk of problems in important operations.
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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