Engineered for demanding environments, this M21 x 70mm Hex Head Cap Screw, constructed from premium 304 stainless steel, offers superior corrosion resistance and robust fastening performance for critical industrial applications.
| Standard | ASME B18 |
| Material | 304 Stainless Steel |
| Finish | Plain |
| Grade | N/A |
| Size | M21 |
| Length | 70mm |
| Head Width | 9mm |
Built to exacting engineering tolerances, this M21 x 70mm hex head cap screw features a precisely machined M21 thread and a nominal length of 70mm, ensuring precise fit and reliable engagement. The head width is engineered to 9mm for compatibility with standard tooling. Fabricated from 304 stainless steel, it exhibits excellent resistance to a wide range of corrosive media, including atmospheric conditions, saltwater, and various acids, making it ideal for marine, chemical processing, and outdoor structural assemblies where longevity and integrity are paramount. Its high tensile strength provides secure and durable joining capabilities.
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 or socket for the 9mm hex head. 2. Thread the M21 cap screw into the pre-tapped hole or nut, ensuring smooth engagement of the M21 threads. 3. Tighten to the required torque specification, verifying proper seating of the hex head.
| Standard System | Designation |
|---|---|
| ISO Equivalent | ISO 898-1 / ISO 4014 |
| DIN Equivalent | DIN 931 / DIN 933 |
| Primary Standard | ASME B18 |
| Tensile Strength | 75,000 psi (515 MPa) |
| Yield Strength | 30,000 psi (205 MPa) |
| Elongation in 2 in. | 40% min |
| Hardness | Rockwell B95 max |
| Carbon (C) | 0.08% max |
| Chromium (Cr) | 18.0 - 20.0% |
| Nickel (Ni) | 8.0 - 10.5% |
| Manganese (Mn) | 2.00% 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 | Good |
| Chemical / Acidic | Not Recommended |
| ❌ Mistake | ✅ Correct Approach |
|---|---|
| Using excessive force during tightening, potentially stripping threads. | Adhere to recommended torque specifications for M21 threads and the specific application material. |
| Using the wrong size wrench, leading to cam-out and fastener damage. | Confirm the wrench or socket size precisely matches the 9mm hex head width. |
A: This Hex Head Cap Screw, 304 Stainless Steel is manufactured from 304 Stainless Steel.
A: Marine hardware and fittings, Chemical processing equipment, Outdoor structural assemblies, Food processing machinery.
Conversion factor: 1 ft-lb ≈ 1.356 Nm
| Status | Mating Component | Standard | Torque Spec | Engineering Notes |
|---|---|---|---|---|
| No verified compatibility data found for this component. | ||||