Thabiso Steel, located in Cape Town, South Africa, is a reputable manufacturer and supplier known for its high-quality alloy steel products. With a solid reputation for reliability and precision, Thabiso Steel provides a wide array of steel solutions tailored to meet various industrial needs. Their Alloy Steel Gr 8.8 Bolts are designed to offer outstanding strength and durability, making them perfect for heavy-duty applications. With a strong commitment to excellence and customer satisfaction, Thabiso Steel plays a vital role in supporting South Africa’s manufacturing and construction industries by supplying robust, trustworthy fasteners that can handle tough environments.
These Alloy Steel Gr 8.8 Bolts are primarily made from carbon, manganese, silicon, along with trace amounts of chromium and molybdenum to boost their strength and wear resistance. They boast a tensile strength of around 800 MPa and a yield strength of about 640 MPa, striking a great balance between toughness and ductility. Their mechanical properties ensure they can resist fatigue and perform reliably under heavy loads and stress, making them suitable for critical structural and mechanical 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 | |
| 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.
Jaxon Steel is a trusted manufacturer and supplier of high-quality Alloy Steel Gr 8.8 Bolts in Cape Town, South Africa. 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!
You’ll find Alloy Steel Gr 8.8 Bolts commonly used in automotive manufacturing, construction, heavy machinery, and structural engineering. Their impressive strength and toughness make them ideal for securing components that face dynamic loads, vibrations, and harsh conditions, such as engines, bridges, and industrial equipment. These bolts are crucial in applications that demand reliable fastening solutions to guarantee safety, durability, and a long service life across various sectors in South Africa.
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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