Strategically located in the bustling heart of Kinshasa, Yoane Steel stands as a trusted partner for industrial growth, dedicated to supplying robust and reliable materials. We specialize in providing high-grade Alloy Steel Gr 8.8 Bolts, engineered to meet the demanding conditions of the Congolese market. Our commitment is to ensure your projects are built on a foundation of unwavering strength and integrity, delivering components that you can count on for performance that endures.
The composition of these bolts is a careful balance of carbon and alloying elements, resulting in a material that offers an excellent strength-to-weight ratio. Mechanically, Grade 8.8 bolts are known for their consistent performance, boasting a tensile strength of 800 MPa and a yield strength of 640 MPa. This makes them a go-to choice for applications requiring dependable load-bearing capacity without the need for the highest levels of hardness, providing a solid and economical solution for a vast range of structural and mechanical fastening needs.
| 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.
Jaxon Steel is a trusted manufacturer and supplier of high-quality Alloy Steel Gr 8.8 Bolts in Kinshasa, Congo. 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 these versatile bolts at work in countless essential applications, forming the critical connections in structural steel frameworks for buildings and bridges, and holding together heavy machinery in mining and manufacturing plants. They are equally vital in the construction of infrastructure projects like transmission towers and in the assembly of automotive components. Essentially, wherever there is a need for a strong, durable, and reliable fastener that can handle significant stress, the Grade 8.8 bolt from Yoane Steel is the trusted component that ensures everything stays securely in place.
Yoane 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 Kinshasa, Congo.
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