Yousef Steel is a leading Riyadh, Saudi Arabia-based manufacturer and supplier of high-quality premium carbon steel fasteners providing a wide spectrum of high-strength solutions such as Carbon Steel 12.9 fasteners. Famous for their accuracy and quality testing, Yousef Steel provides fasteners that are designed to satisfy the rigorous expectations of heavy-duty uses in different industries. Their Grade 12.9 fasteners are designed for situations where maximum tensile strength and reliability are essential. Through state-of-the-art manufacturing plants and rigorous quality checks, Yousef Steel assists customers in various industries like automotive, machinery, infrastructure, and engineering projects domestically and abroad.
Carbon Steel 12.9 fasteners consist of quenched and tempered alloyed medium carbon steel with very high tensile strength. The chemical composition is usually carbon (0.30–0.50%), manganese (0.60–1.20%), and chromium and molybdenum traces for greater hardness and strength. These fasteners have a tensile strength of about 1220 MPa and a yield strength of 1100 MPa with excellent hardness and minimal elongation of about 8%. The 12.9 grade provides a better shear resistance and fatigue and is used in extremely harsh mechanical and structural applications.
| 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.
Yousef Steel is a trustworthy manufacturer and supplier of quality Carbon Steel 12.9 Fasteners in Riyadh, Saudi Arabia. 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 | |
Carbon Steel 12.9 fasteners are extensively used in applications where maximum strength and heavy load and dynamic stress resistance is needed. Widely employed in the automobile, aerospace, heavy equipment, and tool industries, these fasteners are used best for high-torque and high-stress applications. Their performance is of vital importance in fastening parts in engines, suspension systems, industrial presses, and robotics. These fasteners also play a vital role in precision machinery where safety and reliability are paramount. Their hardness and load-carrying capability make them the first choice for applications with little tolerance for failure.
Yousef 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 Riyadh, Saudi Arabia.
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