Engineered for robust assembly, this M21x77mm Hex Head Cap Screw is crafted from high-strength carbon steel. Its precise dimensions and durable construction ensure secure and reliable fastening in critical industrial applications.
| Standard | ISO 9001 |
| Material | Carbon Steel |
| Finish | Galvanized |
| Grade | N/A |
| Size | M21 |
| Length | 77mm |
| Head Width | 12mm |
Designed for demanding industrial environments, this M21x77mm Hex Head Cap Screw offers superior tensile strength and durability due to its high-quality carbon steel construction. The M21 nominal diameter and 77mm length provide substantial clamping force suitable for heavy machinery, structural components, and high-stress assemblies. Its 12mm head width ensures a secure grip for standard tooling, facilitating efficient and reliable installation. The inherent hardness of carbon steel resists deformation under load, making it ideal for applications requiring long-term structural integrity and resistance to vibration.
This component strictly adheres to the tolerances, material specifications, and quality benchmarks set by the world's leading industrial manufacturers.
1. Select the appropriate wrench size for the 12mm hex head. 2. Ensure mating threads are clean and free of debris. 3. Thread the cap screw into the receiving component, applying consistent torque as per engineering specifications.
| Standard System | Designation |
|---|---|
| ISO Equivalent | ISO 898-1 / ISO 4014 |
| DIN Equivalent | DIN 931 / DIN 933 |
| Primary Standard | ISO 9001 |
| Tensile Strength | Standard Commercial Spec |
| Yield Strength | Standard Commercial Spec |
| Hardness | Varies by specific batch |
| Carbon (C) | 0.28 - 0.55% |
| Manganese (Mn) | 0.60 - 0.90% |
| Phosphorus (P) | 0.04% max |
| Sulfur (S) | 0.05% max |
| Bolt Size | Dry Torque (ft-lbs) | Lubricated Torque (ft-lbs) |
|---|---|---|
| M21 | Check Calculator | Reduce by 25% |
| Size / Type | Est. Weight (lbs/100) | Shipping Weight (kg) |
|---|---|---|
| M21 | Varies by dimension | Contact Sales |
| Environment | Rating |
|---|---|
| Indoor / Dry | Excellent |
| Outdoor / Exposed | Excellent |
| Marine / Saltwater | Not Recommended |
| Chemical / Acidic | Not Recommended |
| ❌ Mistake | ✅ Correct Approach |
|---|---|
| Using the wrong size wrench, leading to cam-out and fastener damage. | Always use a wrench that precisely fits the 12mm hex head to ensure proper engagement and prevent stripping. |
| Over-tightening, which can strip threads or cause bolt fracture. | Adhere to recommended torque specifications for the M21 thread size and material to prevent overstressing the fastener. |
A: This Hex Head Cap Screw, Carbon Steel is manufactured from Carbon Steel.
A: Heavy Machinery Assembly, Structural Steel Construction, Industrial Equipment Fabrication.
Conversion factor: 1 ft-lb ≈ 1.356 Nm
| Status | Mating Component | Standard | Torque Spec | Engineering Notes |
|---|---|---|---|---|
| No verified compatibility data found for this component. | ||||