Marzouk Steel, based in Tunis, Tunisia, has built a solid reputation as a reliable manufacturer and supplier of top-notch steel piping components for various industrial and infrastructure needs. The company is well-known for its precision in manufacturing, state-of-the-art production facilities, and unwavering commitment to both international and national quality standards. One of their standout products, the Low Temperature Carbon Steel LF787 Flanges, is specifically engineered to perform exceptionally well in extremely cold environments. With a strong emphasis on durability and customer satisfaction, Marzouk Steel ensures that these flanges provide safe, efficient, and long-lasting performance in oil and gas, petrochemical, power generation, and other industrial piping systems around the globe.
The Low Temperature Carbon Steel LF787 Flanges are crafted with a meticulously controlled chemical composition, which includes carbon, manganese, phosphorus, sulfur, and silicon, all aimed at enhancing strength and toughness. On the mechanical side, these flanges boast impressive tensile strength, dependable yield strength, and outstanding impact resistance even at sub-zero temperatures. Their unique blend of ductility, toughness, and weldability guarantees structural integrity, reduces the risk of brittle fractures, and ensures reliable performance under pressure and thermal stress in critical piping applications.
| Element | Composition |
|---|---|
| Carbon, max | 0.07 |
| Manganese | 0.40–0.70 |
| Phosphorus, max | 0.025 |
| Sulfur, max | 0.025 |
| Silicon [Note A] | 0.40 max |
| Nickel | 0.70–1.00 |
| Chromium | 0.60–0.90 |
| Molybdenum | 0.15–0.25 |
| Copper | 1.00–1.30 |
| Columbium | 0.02 min |
| Vanadium | 0.03 max |
| Tensile Class | Tensile Strength, ksi [MPa] | Yield Strength, min, ksi [MPa] [Note B, C] | Elongation | Reduction of Area, min, % | |
|---|---|---|---|---|---|
| Round Specimen in 4D, min, % | Strip Specimen in 2 Inch [50mm], min, % | ||||
| Class 2 | 65–85 [450–585] | 55 [380] | 20 | 28 | 45 |
| Class 3 | 75–95 [515–655] | 65 [450] | 20 | 28 | 45 |
We provide products that come with both mill test certificates and third-party test certificates, ensuring the highest standards of quality and compliance.
Marzouk Steel is one of the most prominent manufacturers and suppliers of superior quality Low Temperature Carbon Steel LF787 Flanges in Tunis, Tunisia. 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
| ASME/ANSI B 16.5 | LTCS A350 LF787Â Welding Neck Flange, LTCS A350 LF787Â Slip on Flange, Blind Flange, High Hub Blind Flange, Socket Weld Flange, LTCS A350 LF787Â Lap Joint Flange, Threaded Flange, LTCS A350 LF787Â Ring Type Joint Flange |
| PRESSURE CLASS | 150, 300, 400, 600, 900, 1500, 2500 |
| ASME/ANSI B 16.47 | LTCS A350 LF787Â Welding Neck Flange, LTCS A350 LF787Â Blind Flange [Series A & B] |
| PRESSURE CLASS | 75, 150, 300, 400, 600, 900 |
| ASME/ANSI B 16.36 | LTCS A350 LF787Â Welding Neck Flange, LTCS A350 LF787Â Slip on Flange, LTCS A350 LF787Â Threaded Flange |
| PRESSURE CLASS | 300, 400, 600, 900, 1500, 2500 |
| BS 4504 SEC 3.1 | LTCS A350 LF787Â Welding Neck Flange, LTCS A350 LF787Â Hubbed Slip on Flange, LTCS A350 LF787Â Hubbed Threaded Flange, Lapped Pipe End Flange, LTCS A350 LF787Â 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 LF787Â Welding Neck Flange, LTCS A350 LF787Â Hubbed Slip-On Hubbed Threaded, Plate Flange, LTCS A350 LF787Â Loose Plate With Weld On Plate Collar, Blank Flange |
| PRESSURE CLASS | PN 2.5 TO PN 400 |
| BS 1560 BOSS | LTCS A350 LF787Â Welding Neck Flange, Socket Welding Flange, LTCS A350 LF787Â Slip-On Flange, LTCS A350 LF787Â Blind Flange, LTCS A350 LF787Â Screwed Boss Flange, LTCS A350 LF787Â Lapped Flange |
| PRESSURE CLASS | 150, 300, 400, 600, 900, 1500, 2500 |
| BS10 | LTCS A350 LF787Â Welding Neck Flange, LTCS A350 LF787Â Plate Slip-On Flange, LTCS A350 LF787Â Screwed Boss Flange, Slip-On Boss Flange, LTCS A350 LF787Â 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 |
These LF787 Flanges are widely utilized in industries that demand safe and dependable operation in extreme cold conditions. You’ll often find them in oil and gas pipelines, refineries, petrochemical plants, and low-temperature processing units. They’re also a great fit for power generation facilities, offshore platforms, and industrial piping systems that handle pressurized liquids and gases. Thanks to their toughness, durability, and excellent sealing capabilities, these flanges provide secure connections, a long service life, and efficient operation in challenging low-temperature environments.
Marzouk 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 Tunis, Tunisia.
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