This M21 x 29mm hex head cap screw, constructed from high-grade carbon steel, offers superior strength and durability. It's engineered for secure, high-torque fastening in critical industrial assemblies.
| Standard | ASTM A106 |
| Material | Carbon Steel |
| Finish | Zinc Plated |
| Grade | N/A |
| Size | M21 |
| Length | 29mm |
| Head Width | 23mm |
A high-performance industrial component, this M21 x 29mm hex head cap screw is forged from robust carbon steel, providing exceptional tensile and shear strength. The M21 designation signifies its metric thread size, with a nominal diameter of 21mm. The overall length is precisely 29mm, and the hex head features a width of 23mm, ensuring optimal engagement with standard wrenches and sockets for secure tightening. Its material composition offers excellent resistance to deformation under load, making it ideal for heavy-duty machinery, structural components, and demanding mechanical assemblies where reliability is paramount.
This component strictly adheres to the tolerances, material specifications, and quality benchmarks set by the world's leading industrial manufacturers.
1. Ensure the mating threads are clean and free from debris. 2. Hand-thread the cap screw to verify alignment and prevent cross-threading. 3. Tighten the cap screw to the specified torque using a calibrated torque wrench.
| Standard System | Designation |
|---|---|
| ISO Equivalent | ISO 898-1 / ISO 4014 |
| DIN Equivalent | DIN 931 / DIN 933 |
| Primary Standard | ASTM A106 |
| 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 head stripping. | Always use the correct size wrench or socket that fully engages the hex head. |
| Over-tightening, causing thread damage or fastener failure. | Adhere to the recommended torque specifications for the application and fastener size. |
| Reusing damaged or previously stressed fasteners. | Replace any cap screw that shows signs of wear, deformation, or corrosion. |
A: This Hex Head Cap Screw, Carbon Steel is manufactured from Carbon Steel.
A: Heavy Machinery Assembly, Structural Steel Connections, Automotive and Aerospace Components, Industrial Equipment Manufacturing.
Conversion factor: 1 ft-lb ≈ 1.356 Nm
| Status | Mating Component | Standard | Torque Spec | Engineering Notes |
|---|---|---|---|---|
| No verified compatibility data found for this component. | ||||