Phanuphong Steel and Plates, a top-notch manufacturer and supplier based in Bangkok, Thailand, specializes in high-quality **Carbon Steel 12.9 Fasteners** that are perfect for ultra-high-strength industrial, mechanical, and structural applications. With a reputation for precision manufacturing and a commitment to international standards, Phanuphong Steel uses advanced production techniques to ensure that every fastener performs exceptionally well, even in the toughest conditions. These fasteners are a great fit for automotive, heavy machinery, construction, and engineering projects, offering outstanding toughness, durability, and precise dimensions. Catering to both local and international markets, the company delivers versatile and cost-effective fastening solutions that promise long-lasting reliability, impressive mechanical performance, and secure connections in demanding industrial settings.
The **Carbon Steel 12.9 Fasteners** are crafted from high-carbon alloy steel, meticulously quenched and tempered to reach peak tensile strength. They boast a minimum tensile strength of 1,200 MPa and a yield strength of 1,080 MPa, along with excellent hardness, toughness, and resistance to deformation under intense stress. Thanks to their uniform microstructure and superior mechanical properties, these fasteners ensure dimensional stability and exceptional load-bearing capacity. They are perfect for critical applications that demand secure fastening, structural integrity, and high performance in automotive, machinery, construction, and industrial engineering projects.
| Carbon Steel 12.9 | C | P | S | B |
| 0.28-0.5 | 0.025 | 0.025 | 0.003 |
| Nominal thread diameter size range [mm] | Proof strength [MPa] | Yield strength (min) [MPa] | Tensile strength (min) [MPa] | Hardness [Rockwell] |
| 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.
Phanuphong Steel is a trustworthy manufacturer and supplier of quality Carbon Steel 12.9 Fasteners in Bangkok, Thailand. 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 12.9 Fasteners needs!
| DIA | M4 | M5 | M6 | M8 | M10 | M12 | M14 | M16 | M18 | M20 | M22 | M24 | M27 | M30 | M33 | M36 | M39 | M42 | M45 | M48 | M52 |
| Pitch | 0.7 | 0.8 | 1 | 1.25 | 1.5 | 1.75 | 2 | 2.5 | 3 | 3.5 | 4 | 4.5 | 5 | ||||||||
| Grade A upto length | 40 | 50 | 60 | 80 | 100 | 120 | 140 | 150 | Grade A not applicable to these dia’s | ||||||||||||
| Head Across Flat (S) Nom = Max Min Grade A Grade 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 | Grade A not applicable to these dia’s | |||||||||
| 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 (K) Nom Tol + or – Grade A Grade 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 | Grade A not applicable to these dia’s | |||||||||||||||||
| 0.2 | 0.24 | 0.29 | 0.35 | 0.42 | 0.5 | ||||||||||||||||
| Across corners e Min Grade A Grade 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 | Grade A not applicable to these dia’s | ||||||||
| 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 | |
| Major Dia at thread (min) | 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 (max) | 3.978 | 4.976 | 5.974 | 7.972 | 9.968 | 11.966 | 13.962 | 15.962 | 17.958 | 19.958 | 21.958 | 23.952 | 26.952 | 29.947 | 32.947 | 35.94 | 38.94 | 41.937 | 44.937 | 47.929 | 51.929 |
| Thread Length (b) For lengths < or = 125mm For lengths > 125mm <= 200mm For lengths > 200mm | 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 | |
You’ll find **Carbon Steel 12.9 Fasteners** widely used in automotive assemblies, heavy machinery, construction, structural frameworks, and industrial equipment that require extreme strength. They’re ideal for high-load joints, mechanical components, structural connections, and any application where maximum tensile strength and durability are essential. Their blend of toughness, precision, and high-strength performance makes them a go-to choice for demanding projects.
Phanuphong 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 Bangkok, Thailand.
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