Luke Steel, headquartered in Houston, Houstan, is a prominent producer and supplier of ASTM A350 LF2 low-temperature carbon steel flanges for industries that work in cryogenic and sub-zero temperatures. Renowned for its quality, accuracy, and customer support, Luke Steel delivers flanges that provide superior toughness and reliability even at temperatures of up to -46°C (-50°F). Manufactured as per global standards, these flanges have been globally accepted for vital applications in oil & gas, LNG, petrochemicals, and power generation. With a strong supply chain and sophisticated manufacturing setup, Luke Steel provides on-time delivery and reliable product performance globally.
ASTM A350 LF2 flanges are produced using low-temperature carbon steel with carbon (≤0.30%), manganese (0.60–1.35%), silicon (0.15–0.30%), and trace metals such as nickel, chromium, molybdenum, vanadium, copper, and niobium. The flanges experience normalizing or heat treatments of quenching and tempering for improved performance in sub-zero temperatures. They provide tensile strength of 485–655 MPa, yield strength ≥250 MPa, elongation ≥22%, and impact toughness ≥20 J at -46°C with maximum hardness of 197 HB. They have remarkable ductility, resistance to fracture, and reliability in very low temperatures.
| 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.
Luke Steel is one of the most prominent manufacturers and suppliers of superior quality Low Temperature Carbon Steel LF2 Flanges in Houstan, USA. 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.
| 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 |
ASTM A350 LF2 low-temperature carbon steel flanges are extensively employed in cold climatic conditions requiring consistent mechanical performance in the same. Major uses are in heat exchangers, LNG pipelines, cryogenic storage tanks, and offshore oil & gas facilities. They are essential in petrochemical and chemical plants where the effects of low temperature lead to material brittleness. These are also utilized in power plants and in refinery piping systems where there is a need for handling pressure and temperature consistently. With superior weldability and impact properties, A350 LF2 flanges provide leak-free and safe connections in piping systems that operate in extreme or sub-zero conditions.
Luke 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 Houstan, USA.
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