Marzouk Steel, based in Tunis, Tunisia, stands out as a top manufacturer and supplier of high-quality Alloy Steel Gr 8.8 bolts. These bolts are celebrated for their exceptional strength, durability, and precise engineering, making them perfect for the rigorous demands of industrial and mechanical applications. By utilizing cutting-edge manufacturing methods and strict quality control measures, Marzouk Steel guarantees that every Gr 8.8 bolt provides dependable performance and longevity. The company caters to various sectors, including automotive, construction, heavy machinery, and engineering, and is well-known for delivering top-notch fastening solutions that offer remarkable tensile strength, corrosion resistance, and mechanical stability even in tough operational conditions.
Alloy Steel Gr 8.8 bolts are crafted from premium alloy steel, which includes carbon, manganese, chromium, and molybdenum, all designed for outstanding strength, toughness, and wear resistance. These bolts undergo heat treatment to boost their hardness and durability, resulting in impressive mechanical properties such as a tensile strength of around 800–950 MPa, a yield strength of 640–760 MPa, and an elongation of 10–12%. Their remarkable resistance to deformation, wear, and fatigue makes them a reliable choice for secure fastening in high-stress industrial and mechanical assemblies, making them ideal for critical applications.
| AStm Standards | DIN ISO EN 4017 & 4014 DIN 933 / 931 & IS 1363 / 1363 |
| Size | Diameter 20 to 100 Milimeter / Inch 3/4 to 3.1/2 |
| Surface Finish | Zinc plated / Plain / Hot dip galvanised |
| CLASS | MATERIAL AND TREATMENT | C | C | P | S | B | TEMPERING TEMP. [C] |
|---|---|---|---|---|---|---|---|
| MIN | MAX | MAX | MAX | MAX | |||
| 8.8 | CARBON STEEL WITH ADDITIVES (E.G. B, MN OR CR) QUENCHED AND TEMPERED | 0.15 (D) | 0.4 | 0.025 | 0.025 | 0.003 | 425 |
| CARBON STEEL QUENCHED AND TEMPERED | 0.25 | 0.55 | 0.035 | 0.025 |
| Grades | Size Range | PS [MPa] | YS (min) [MPa] | TS (min) [MPa] | Hardness [Rockwell] |
|---|---|---|---|---|---|
| Class 8.8 | Under M16 | 580 | 640 | 800 | |
| 17-72 | 600 | 660 | 830 | C23–34 |
| Bolt Dia | Body Dia | Head Dia(F) | Head Height (H) | Degree of Slope | |||
|---|---|---|---|---|---|---|---|
| (D) | Max | Max Edge Sharp | Min Edge Sharp | Absolute Min Rounded | Max | Min | Â |
| 1/2 | 0.515 | 0.935 | 0.905 | 0.845 | 0.269 | 0.233 | 78° to 82° |
| 5/8 | 0.642 | 1.169 | 1.132 | 1.066 | 0.336 | 0.292 | 78° to 82° |
| 3/4 | 0.768 | 1.402 | 1.357 | 1.285 | 0.403 | 0.349 | 78° to 82° |
| 7/8 | 0.895 | 1.637 | 1.584 | 1.511 | 0.47 | 0.408 | 78° to 82° |
| 1 | 1.022 | 1.869 | 1.81 | 1.735 | 0.537 | 0.466 | 78° to 82° |
| 1-1/8 | 1.149 | 2.104 | 2.037 | 1.962 | 0.604 | 0.525 | 78° to 82° |
| 1-1/4 | 1.277 | 2.337 | 2.262 | 2.187 | 0.671 | 0.582 | 78° to 82° |
| 1-3/8 | 1.404 | 2.571 | 2.489 | 2.414 | 0.738 | 0.641 | 78° to 82° |
| 1-1/2 | 1.531 | 2.804 | 2.715 | 2.64 | 0.805 | 0.698 | 78° to 82° |
| Dimensions per ASME B18.5 1990 (R 1998) | |||||||
| Diameter Chart | M4 | M5 | M6 | M8 | M10 | M12 | M14 | M16 | M18 | M20 | M22 | M24 | M27 | M30 | M33 | M36 | M39 | M42 | M45 | M48 | M52 |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Pitch List | 0.7 | 0.8 | 1 | 1.25 | 1.5 | 1.75 | 2 | 2.5 | 3 | 3.5 | 4 | 4.5 | 5 | ||||||||
| GR A Length | 40 | 50 | 60 | 80 | 100 | 120 | 140 | 150 | Grade A not applicable to these dia’s | ||||||||||||
Head Across Flat (S) Nom = Max Min GR A GR B | 7 | 8 | 10 | 13 | 16 | 18 | 21 | 24 | 27 | 30 | 34 | 36 | 41 | 46 | 50 | 55 | 60 | 65 | 70 | 75 | 80 |
| 6.78 | 7.78 | 9.78 | 12.73 | 15.73 | 17.73 | 20.67 | 23.67 | 26.67 | 29.67 | 33.38 | 35.38 | GR A not applicable to these diameters | |||||||||
| 6.64 | 7.64 | 9.64 | 12.57 | 15.57 | 17.57 | 20.16 | 23.16 | 26.16 | 29.16 | 33 | 35 | 40 | 45 | 49 | 53.8 | 58.8 | 63.1 | 68.1 | 73.1 | 78.1 | |
Head Height Nom Tol + or – GR A GR B | 2.8 | 3.5 | 4 | 5.3 | 6.4 | 7.5 | 8.8 | 10 | 11.5 | 12.5 | 14 | 15 | 17 | 18.7 | 21 | 22.5 | 25 | 26 | 28 | 30 | 33 |
| 0.125 | 0.15 | 0.18 | 0.215 | GR A not applicable to these diameters | |||||||||||||||||
| 0.2 | 0.24 | 0.29 | 0.35 | 0.42 | 0.5 | ||||||||||||||||
Across corners e Min GR A GR B | 7.66 | 8.79 | 11.05 | 14.38 | 17.77 | 20.03 | 23.36 | 26.75 | 30.14 | 33.53 | 37.72 | 39.98 | GR A not applicable to these diameters | ||||||||
| 7.5 | 8.63 | 10.89 | 14.2 | 17.59 | 19.85 | 22.78 | 26.17 | 29.56 | 32.95 | 37.29 | 39.55 | 45.2 | 50.85 | 55.37 | 60.79 | 66.44 | 71.3 | 76.95 | 82.6 | 88.25 | |
Thread Length (b) For lengths < or = 125ilimeter For lengths > 12ilimeter <= 200milimeter For lengths > 200ilimeter | 14 | 16 | 18 | 22 | 26 | 30 | 34 | 38 | 42 | 46 | 50 | 54 | 60 | 66 | Not specified as full thread recommended | ||||||
| 20 | 22 | 24 | 28 | 32 | 36 | 40 | 44 | 48 | 52 | 56 | 60 | 66 | 72 | 78 | 84 | 90 | 96 | 102 | 108 | 116 | |
| 33 | 35 | 37 | 41 | 45 | 49 | 53 | 57 | 61 | 65 | 69 | 73 | 79 | 85 | 91 | 97 | 103 | 109 | 115 | 121 | 129 | |
| Major Diameter at thread (minimum) | 3.838 | 4.826 | 5.794 | 7.76 | 9.732 | 11.701 | 13.682 | 15.682 | 17.623 | 19.623 | 21.623 | 23.577 | 26.577 | 29.522 | 32.522 | 35.465 | 38.465 | 41.437 | 44.437 | 47.399 | 51.399 |
| Major Dia at thread (maximum) | 3.978 | 4.976 | 5.974 | 7.972 | 9.968 | 11.966 | 13.962 | 15.962 | 17.958 | ||||||||||||
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 trusted manufacturer and supplier of high-quality Alloy Steel Gr 8.8 Bolts in Tunis, Tunisia. We specialize in premium steel products, including Alloy Steel, Carbon Steel, Mild Steel and Galvanized Steel, with a strong focus on Carbon Steel Sheet and Plates. Our extensive inventory also includes Pipes, Tubes, Flanges, Forged Fittings and Bars. Committed to fast delivery and exceptional customer service, we use only the finest raw materials to ensure superior strength, durability and performance for critical industrial applications. Contact us today for all your Alloy Steel Gr 8.8 Bolts needs!
These Alloy Steel Gr 8.8 bolts find extensive use in the automotive, construction, heavy machinery, and industrial equipment sectors. They play a crucial role in high-stress fastening for engines, gear assemblies, structural frameworks, and mechanical systems. With their superior tensile strength, toughness, and corrosion resistance, these bolts ensure consistent performance, minimize maintenance needs, and offer a long service life. Engineers and industrial operators trust Alloy Steel Gr 8.8 bolts as their go-to choice for applications that demand precision, strength, and high-performance fastening solutions in challenging 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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