Thabiso Steel, located in Cape Town, South Africa, has made a name for itself as a top-notch manufacturer and supplier of high-quality Alloy Steel F91 Bars. These bars are celebrated for their incredible strength, durability, and ability to withstand high temperatures and corrosion. They’re specifically crafted to meet the rigorous demands of industries like power generation, petrochemicals, and engineering. Thabiso Steel prides itself on precision manufacturing and strict adherence to international standards, offering Alloy Steel F91 Bars in a variety of sizes and finishes to cater to different industrial needs. Their dedication to quality, innovation, and customer satisfaction has established them as a reliable name in the South African steel market.
Alloy Steel F91 Bars are made from a blend of chromium, molybdenum, vanadium, carbon, and trace amounts of manganese, silicon, and nickel. This unique mix provides outstanding mechanical properties, such as high tensile strength, excellent creep resistance, and remarkable oxidation resistance at elevated temperatures. The bars are known for their exceptional hardness, toughness, and stability under pressure, making them perfect for high-stress, high-temperature environments where reliability and performance are crucial.
| Specifications | ASTM A182, ASME SA182 |
|---|---|
| Dimensions | EN, DIN, JIS, ASTM, BS, ASME, AISI |
| Range | 5mm to 500mm Dia in 100mm to 6000mm Length |
| Diameter | 10 mm To 200 mm |
| Thickenss | 0.5mm to 500mm Diameter |
| High Speed Steel (HSS), HCHCR & OHNS in Grade | M2, M3, M35, M42, T-1, T-4, T-15, T-42, D2, D3, H11, H13, OHNS-01 & EN52 |
| Finish | Black, Bright Polished, Rough Turned, NO.4 Finish, Matt Finish, BA Finish |
| Length | 1000 mm Long To 6000 mm Long |
| Form | Round, Square, Hex (A/F), Rectangle, Billet, Ingot, Forging Etc. |
Alloy Steel Rods ASTM Specification
| Internal Standard | EN | DIN | SAE/AISI |
|---|---|---|---|
| EN 18 | EN 18 | 37Cr4 | 5140 |
| EN 19 | EN 19 | 42Cr4Mo2 | 4140/4142 |
| EN 24 | EN 24 | 34CrNiMo6 | 4340 |
| EN 353 | EN 353 | – | – |
| EN 354 | EN 354 | – | 4320 |
| SAE 8620 | EN 362 | – | SAE 8620 |
| EN 1 A | EN 1 A | 9SMn28 | 1213 |
| SAE 1146 | EN 8M | – | SAE 1146 |
| EN 31 | EN 31 | 100Cr6 | SAE 52100 |
| EN 45 | EN 45 | 55Si7 | 9255 |
| EN 45A | EN 45A | 60Si7 | 9260 |
| 50Crv4 | EN 47 | 50CrV4 | 6150 |
| SAE 4130 | – | 25CrMo4 | SAE 4130 |
| SAE 4140 | – | 42CrMO4 | SAE 4140 |
| 20MNCR5 | – | – | – |
| Element | C | Cr | Mn | Mo | P | S | Si | Ni |
|---|---|---|---|---|---|---|---|---|
| F5 | 0.15 Max | 4.0-6.0 | 0.30-0.60 | 0.44-0.65 | 0.035 Max | 0.030 Max | 0.50 Max | 0.50 Max |
| F1 | 0.15 Max | 3.0-5.0 | 0.30-0.60 | 0.40-0.50 | 0.035 Max | 0.030 Max | 0.50 Max | 0.50 Max |
| F22 | 0.05-0.15 | 2.00-2.50 | 0.30-0.60 | 0.90-1.10 | 0.035 Max | 0.040 Max | 0.50 Max | – |
| F91 | 0.08-0.12 | 8.0-9.5 | 0.30-0.60 | 0.85-1.05 | 0.020 Max | 0.010 Max | 0.20-0.50 | 0.40 Max |
| F9 | 0.15 Max | 8.0-10.0 | 0.30-0.60 | 0.90- 1.10 | 0.030 Max | 0.030 Max | 0.50- 1.00 | – |
| 42CrMo4 | 0.380 – 0.45 % | 0.90 – 1.20 % | 0.60 – 0.90 % | 0.15 – 0.30 % | ≤ 0.035 % | ≤ 0.035 % | – | – |
| F11 | 0.10-0.20 | 1.00-1.50 | 0.40-0.65 | 0.44-0.65 | 0.025 Max | 0.040 Max | 0.50-0.80 | – |
| Properties | Conditions | ||
|---|---|---|---|
| T (°C) | Treatment | ||
| Density (×1000 kg/m3) | 7.7-8.03 | 25 | |
| Elastic Modulus (GPa) | 190-210 | 25 | |
| Tensile Strength (Mpa) | 1158 | 25 | oil quenched, fine grained, tempered at 425°C |
| Yield Strength (Mpa) | 1034 | ||
| Reduction in Area (%) | 53 | ||
| Hardness (HB) | 335 | 25 | oil quenched, fine grained, tempered at 425°C |
We provide products that come with both mill test certificates and third-party test certificates, ensuring the highest standards of quality and compliance.
These Alloy Steel F91 Bars find extensive use in power plants, refineries, and chemical processing industries, thanks to their strength and temperature resilience. They’re ideal for crafting boiler components, heat exchangers, pressure vessels, and piping systems that endure extreme thermal and mechanical stress. Moreover, these bars are utilized in turbine parts, steam lines, and superheater tubes, where long-lasting performance and corrosion resistance are essential. With their superior mechanical and thermal properties, Alloy Steel F91 Bars are vital for critical industrial and engineering applications around the globe.
| SIZE IN INCHES | ROUND | SQUARE | OCTAGON | HEXAGON | SIZE IN INCHES | ROUND | SQUARE | OCTAGON | HEXAGON |
| 1/16 | .010 | .013 | .011 | .012 | 11/16 | 1.262 | 1.607 | 1.333 | 1.392 |
| 5/64 | .017 | .022 | .018 | .019 | 45/64 | 1.320 | 1.681 | 1.394 | 1.456 |
| 3/32 | .023 | .029 | .024 | .025 | 23/32 | 1.380 | 1.756 | 1.487 | 1.521 |
| 7/64 | .031 | .039 | .033 | .034 | 47/64 | 1.440 | 1.834 | 1.521 | 1.588 |
| 1/8 | .042 | .053 | .044 | .046 | 3/4 | 1.502 | 1.913 | 1.586 | 1.656 |
| 9/64 | .053 | .067 | .056 | .058 | 25/32 | 1.630 | 2.075 | 1.721 | 1.797 |
| 5/32 | .065 | .083 | .069 | .072 | 13/16 | 1.763 | 2.245 | 1.862 | 1.944 |
| 11/64 | .079 | .100 | .083 | .087 | 27/32 | 1.901 | 2.421 | 2.008 | 2.096 |
| 3/16 | .094 | .120 | .099 | .104 | 7/8 | 2.045 | 2.603 | 2.159 | 2.254 |
| 13/64 | .110 | .140 | .116 | .121 | 29/32 | 2.193 | 2.792 | 2.316 | 2.418 |
| 7/32 | .128 | .163 | .135 | .141 | 15/16 | 2.347 | 2.988 | 2.479 | 2.588 |
| 15/64 | .147 | .187 | .155 | .162 | 31/32 | 2.506 | 3.191 | 2.646 | 2.763 |
| 1/4 | .167 | .213 | .176 | .184 | 1 | 2.670 | 3.400 | 2.820 | 2.945 |
|---|---|---|---|---|---|---|---|---|---|
| 17/64 | .188 | .240 | .199 | .207 | 1-1/16 | 3.015 | 3.838 | 3.183 | 3.324 |
| 9/32 | .211 | .269 | .223 | .233 | 1-1/8 | 3.380 | 4.303 | 3.569 | 3.727 |
| 19/64 | .235 | .300 | .248 | .259 | 1-3/16 | 3.766 | 4.795 | 3.977 | 4.152 |
| 5/16 | .261 | .332 | .275 | .288 | 1-1/4 | 4.172 | 5.313 | 4.407 | 4.601 |
| 21/64 | .288 | .360 | .304 | .318 | 1-5/16 | 4.600 | 5.857 | 4.858 | 5.072 |
| 11/32 | .316 | .402 | .334 | .348 | 1-3/8 | 5.049 | 6.428 | 5.332 | 5.567 |
| 23/64 | .345 | .439 | .364 | .381 | 1-7/16 | 5.518 | 7.026 | 5.827 | 6.085 |
| 3/8 | .376 | .478 | .397 | .414 | 1-1/2 | 6.008 | 7.650 | 6.345 | 6.625 |
| 25/64 | .408 | .519 | .431 | .450 | 1-9/16 | 6.519 | 8.301 | 6.885 | 7.189 |
| 13/32 | .441 | .561 | .466 | .486 | 1-5/8 | 7.051 | 8.978 | 7.446 | 7.775 |
| 27/64 | .475 | .605 | .502 | .524 | 1-11/16 | 7.604 | 9.682 | 8.030 | 8.385 |
| 7/16 | .511 | .651 | .540 | .564 | 1-3/4 | 8.178 | 10.41 | 8.634 | 9.018 |
| 29/64 | .548 | .698 | .579 | .604 | 1-13/16 | 8.773 | 11.17 | 9.265 | 9.673 |
| 15/32 | .587 | .747 | .620 | .647 | 1-7/8 | 9.388 | 11.95 | 9.911 | 10.35 |
| 31/64 | .627 | .798 | .662 | .692 | 1-15/16 | 10.02 | 12.76 | 10.58 | 11.05 |
| 1/2 | .668 | .850 | .705 | .736 | 2 | 10.68 | 13.60 | 11.28 | 11.78 |
| 33/64 | .710 | .904 | .750 | .783 | 2-1/16 | 11.36 | 14.46 | 11.99 | 12.53 |
| 17/32 | .754 | .960 | .796 | .831 | 2-1/8 | 12.06 | 15.35 | 12.73 | 13.30 |
| 35/64 | .799 | 1.017 | .844 | .881 | 2-3/16 | 12.78 | 16.27 | 13.49 | 14.09 |
| 9/16 | .845 | 1.076 | .892 | .932 | 2-1/4 | 13.52 | 17.21 | 14.27 | 14.91 |
| 37/64 | .893 | 1.136 | .943 | .985 | 2-5/16 | 14.28 | 18.18 | 15.08 | 15.75 |
| 19/32 | .941 | 1.199 | .994 | 1.038 | 2-3/8 | 15.06 | 19.18 | 15.91 | 16.61 |
| 39/64 | .992 | 1.263 | 1.048 | 1.094 | 2-7/16 | 15.87 | 20.20 | 16.75 | 17.49 |
| 5/8 | 1.043 | 1.328 | 1.102 | 1.150 | 2-1/2 | 16.69 | 21.25 | 17.62 | 18.40 |
| 41/64 | 1.096 | 1.395 | 1.207 | 1.209 | 2-9/16 | 17.53 | 22.33 | 18.52 | 19.34 |
| 21/32 | 1.150 | 1.464 | 1.214 | 1.268 | 2-5/8 | 18.40 | 23.43 | 19.43 | 20.29 |
| 43/64 | 1.205 | 1.535 | 1.272 | 1.329 | 2-11/16 | 19.29 | 24.56 | 20.37 | 21.27 |
Alloy steel bars are extensively applied in many industries because of their strength, durability, and resistance to corrosion. In building construction, they are used for structural frames, bridges, and skyscrapers. The automotive sector depends on them for the production of engine parts, axles, and transmission gears.In heavy machinery, they are used in shafts, rollers, and tool manufacturing. Their low weight but high strength characteristics are useful to the aerospace industry from the use in engine components and landing gear of airplanes. Alloy steel bars are additionally applied in the oil and gas, shipbuilding, and power generation industries where efficiency and safety demand high performance under harsh environments.
ThabisoSteel 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 Cape Town, South Africa.
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