Marzouk Steel is a leading producer and supplier of superior quality steel products in Tunis, Tunisia, which deals in durable and precision-fabricated items. With years of industry experience, we provide a wide range of steel components like carbon steel bolts, to meet different industrial needs. We believe in excellence, innovation, and customer delight to provide high-quality products that conform to global standards. For construction, vehicle, or heavy engineering applications, Marzouk Steel offers robust and reliable solutions. Choose Marzouk Steel for high-quality steel products with higher strength and performance, backed by unmatched service and expertise.
Carbon steel bolts consist mainly of iron (Fe) with varying amounts of carbon (C), typically 0.05%–0.90%, affecting strength and hardness. Other constituents are manganese (Mn) 0.30%–1.65% for toughness, phosphorus (P) ≤0.04% and sulfur (S) ≤0.05% for machinability. Bolts possess good tensile strength (400–1,200 MPa), yield strength (250–1,000 MPa), and hardness (Rockwell B70–C45) based on the grade. Bolts exhibit excellent ductility, fair wear resistance, and poor corrosion resistance. Low-carbon varieties provide versatility, and high-carbon varieties provide greater strength and durability. Their mechanical characteristics make them fit for demanding industrial, automotive and construction applications requiring strong fastening solutions.
Specification :Â ASTM F568 / ASME SF568
Dimension :Â DIN, ISO, ASTM, JIS, BS, GB, IS and all International Standards
Size Range :Â M3 – M56 | 3/6″ to 2″ | Custom Sizes
Length :Â 3 mm to 200 mm
Type : Hex Head Bolts, Square Bolts, U bolts, Eye bolts, T bolt, Hex Bolt, Lag Bolts, Counter sunk Bolts
| Grade | C | P | S | B |
| Carbon Steel 10.9 | 0.20-0.55 | 0.025 | 0.025 | 0.003 |
| Carbon Steel 12.9 | 0.28-0.5 | 0.025 | 0.025 | 0.003 |
| Element | Nominal thread diameter size range [mm] | Proof strength [MPa] | Yield strength (min) [MPa] | Tensile strength (min) [MPa] | Hardness [Rockwell] |
| Carbon Steel 10.9 | 5–100 | 830 | 940 | 1040 | C32–39 |
| Carbon Steel 12.9 | 1.6–100 | 970 | 1100 | 1220 | C39–44 |
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 a trustworthy manufacturer and supplier of quality Carbon Steel Bolts in Tunis, Tunisia. We specialize in top-grade steel products like Carbon Steel, Alloy Steel, Mild Steel, and Galvanized Steel, with the main focus being on Carbon Steel Sheets and Plates. Our vast inventory also includes Pipes, Tubes, Flanges, Forged Fittings, and Bars. Committed to fast delivery and excellent customer service, we use only the finest raw materials to deliver excellent strength, durability, and performance for high-demand industrial uses. Contact us today for all your Carbon Steel Bolt needs!
| Heavy Hex Bolt Diameter | Â D | Â F | Â C | Â H | |||||
|  Body Diameter  |  Width Across Flats |  Width Across Corners |  Height | ||||||
|  Max |  Basic |  Max    |  Min     |  Max |  Min |  Basic |  Max    |  Min    | |
| 1/2 | 0.515 | 7/8 | 0.875 | 0.850 | 1.010 | 0.969 | 11/32 | 0.364 | 0.302 |
| 5/8 | 0.642 | 1-1/16 | 1.062 | 1.031 | 1.227 | 1.175 | 27/64 | 0.444 | 0.378 |
| 3/4 | 0.768 | 1-1/4 | 1.250 | 1.212 | 1.443 | 1.383 | 1/2 | 0.524 | 0.455 |
| 7/8 | 0.895 | 1-7/16 | 1.438 | 1.394 | 1.660 | 1.589 | 37/64 | 0.604 | 0.531 |
| 1 | 1.022 | 1-5/8 | 1.625 | 1.575 | 1.876 | 1.796 | 43/64 | 0.700 | 0.591 |
| 1-1/8 | 1.149 | 1-13/16 | 1.812 | 1.756 | 2.093 | 2.002 | 3/4 | 0.780 | 0.658 |
| 1-1/4 | 1.277 | 2 | 2.00 | 1.938 | 2.309 | 2.209 | 27/32 | 0.876 | 0.749 |
| 1-3/8 | 1.404 | 2-3/16 | 2.188 | 2.119 | 2.526 | 2.416 | 29/32 | 0.940 | 0.810 |
| 1-1/2 | 1.531 | 2-3/8 | 2.375 | 2.300 | 2.742 | 2.622 | 1 | 1.036 | 0.902 |
| 1-3/4 | 1.785 | 2-3/4 | 2.750 | 2.662 | 3.175 | 3.035 | 1-5/32 | 1.196 | 1.054 |
| 2 | 2.039 | 3-1/8 | 3.125 | 3.025 | 3.608 | 3.449 | 1-11/32 | 1.388 | 1.175 |
| 2-1/4 | 2.305 | 3-1/2 | 3.500 | 3.388 | 4.041 | 3.862 | 1-1/2 | 1.548 | 1.327 |
| 2-1/2 | 2.559 | 3-7/8 | 3.875 | 3.750 | 4.474 | 4.275 | 1-21/32 | 1.708 | 1.479 |
| Nominal or Basic Product Diameter | E | F | G | H | J | LT (Thread Length) | Y | ||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Body Diameter | Width Across Flats | Width Across Corners | Head Height | Wrenching Height | For Bolt Lengths | For Bolt Lengths | Transition Thread Length | ||||||||
| 1/4 | 0.25 | 0.25 | 0.245 | 7/16 | 0.438 | 0.428 | 0.505 | 0.488 | 5/32 | 0.163 | 0.150 | 0.106 | 0.750 | 1.000 | 0.250 |
| 5/16 | 0.3125 | 0.3125 | 0.3065 | 1/2 | 0.500 | 0.489 | 0.577 | 0.557 | 13/64 | 0.211 | 0.195 | 0.140 | 0.875 | 1.125 | 0.278 |
| 3/8 | 0.375 | 0.375 | 0.369 | 9/16 | 0.562 | 0.551 | 0.650 | 0.628 | 15/64 | 0.243 | 0.226 | 0.160 | 1.000 | 1.250 | 0.312 |
| 7/16 | 0.4375 | 0.4375 | 0.4305 | 5/8 | 0.625 | 0.612 | 0.722 | 0.698 | 9/32 | 0.291 | 0.272 | 0.195 | 1.125 | 1.375 | 0.357 |
| 1/2 | 0.5 | 0.5 | 0.493 | 3/4 | 0.750 | 0.736 | 0.866 | 0.840 | 5/16 | 0.323 | 0.302 | 0.215 | 1.250 | 1.500 | 0.385 |
| 9/16 | 0.5625 | 0.5625 | 0.5545 | 13/16 | 0.812 | 0.798 | 0.938 | 0.910 | 23/64 | 0.371 | 0.348 | 0.250 | 1.375 | 1.625 | 0.417 |
| 5/8 | 0.625 | 0.625 | 0.617 | 15/16 | 0.938 | 0.922 | 1.083 | 1.051 | 25/64 | 0.403 | 0.378 | 0.269 | 1.500 | 1.750 | 0.455 |
| 3/4 | 0.75 | 0.75 | 0.741 | 1-1/8 | 1.125 | 1.100 | 1.299 | 1.254 | 15/32 | 0.483 | 0.455 | 0.324 | 1.750 | 2.000 | 0.500 |
| 7/8 | 0.875 | 0.875 | 0.866 | 1-5/16 | 1.312 | 1.285 | 1.516 | 1.465 | 35/64 | 0.563 | 0.531 | 0.378 | 2.000 | 2.250 | 0.556 |
| 1 | 1 | 1 | 0.99 | 1-1/2 | 1.500 | 1.469 | 1.732 | 1.675 | 39/64 | 0.627 | 0.591 | 0.416 | 2.250 | 2.500 | 0.625 |
| 1-1/8 | 1.125 | 1.125 | 1.114 | 1-11/16 | 1.688 | 1.631 | 1.949 | 1.859 | 11/16 | 0.718 | 0.658 | 0.461 | 2.500 | 2.750 | 0.714 |
| 1-1/4 | 1.25 | 1.25 | 1.239 | 1-7/8 | 1.875 | 1.812 | 2.165 | 2.066 | 25/32 | 0.813 | 0.749 | 0.530 | 2.750 | 3.000 | 0.714 |
| 1-1/2 | 1.5 | 1.5 | 1.488 | 2-1/4 | 2.250 | 2.175 | 2.598 | 2.480 | 15/16 | 0.974 | 0.902 | 0.640 | 3.250 | 3.500 | 0.833 |
Various industries often utilize carbon steel bolts for their indispensable fastening solutions. Among your construction, automotive, and manufacturing applications, they are very useful in securing structural components, machinery parts, and heavy equipment where high tensile strength is needed. Other applications of carbon steel bolts involve the fabrication of bridges, pipelines, and industrial machinery due to their wear and impact resistance. Over the years, the chances for them to corrode exist; however, these can be coated or treated for enhanced corrosion resistance, making them very versatile inside or outside.
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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