Esha Steel has built a solid reputation as a reliable manufacturer and supplier of top-notch Alloy Steel Gr 8.8 Bolts right here in Kolkata. They cater to industries that need strong and durable fastening solutions. Thanks to their state-of-the-art manufacturing facilities and rigorous quality control measures, Esha Steel ensures that their bolts not only meet international standards but also perform exceptionally well in tough environments. These Alloy Steel Gr 8.8 Bolts are highly regarded for their impressive strength, resistance to corrosion, and long-lasting service life. You’ll find them widely used in various sectors, including construction, automotive, oil and gas, and heavy engineering. Esha Steel is dedicated to delivering on time, ensuring precision in engineering, and maintaining consistent product excellence.
The Alloy Steel Gr 8.8 Bolts are crafted from medium carbon alloy steel, enriched with elements like carbon, manganese, chromium, and molybdenum, all of which boost their strength and durability. They undergo a process of quenching and tempering to enhance their hardness and mechanical properties. These bolts provide high tensile and yield strength, outstanding wear resistance, and excellent fatigue performance. Their sturdy composition guarantees stability even under high pressure, dynamic loads, and fluctuating temperatures, making them perfect for critical applications where reliability and load-bearing capacity are a must.
| 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.
Esha Steel is a trusted manufacturer and supplier of high-quality Alloy Steel Gr 8.8 Bolts in Kolkata India. 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!
In industries that demand strong and trustworthy fastening components, Alloy Steel Gr 8.8 Bolts are a go-to choice. In construction, they’re essential for steel structures, bridges, and heavy frameworks. The automotive and machinery sectors depend on them for engines, suspension systems, and high-load mechanical assemblies. They’re also a staple in oil and gas facilities, petrochemical plants, and power generation units, thanks to their ability to withstand stress, vibration, and harsh operating conditions. Their remarkable durability and mechanical performance make them the ideal choice for long-term, heavy-duty industrial applications.
Esha 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 Kolkata India.
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