COMPREHENSIVE TECHNICAL ANALYSIS AND DATASHEET OF ASTM A194 GRADE 8N NUTS
ASTM A194 Grade 8N specifies premium austenitic stainless steel nuts manufactured from AISI Type 304N. This specialized grade takes the legendary 18/8 corrosion resistance of standard Grade 8 and significantly boosts its mechanical capabilities through the precise metallurgical addition of Nitrogen (N). Nitrogen acts as a powerful solid-solution strengthening agent, substantially increasing the material's yield strength while simultaneously enhancing its resistance to pitting corrosion.
Standard Grade 8N nuts are expertly machined from solution-treated bar stock, providing an exceptional balance of high tensile strength and chemical resistance for aggressive pressure piping environments.
■ Product Overview & Specifications
ASTM A194 Grade 8N represents the industry benchmark for high-strength, nitrogen-alloyed austenitic pressure piping components.
| Material Classification | Nitrogen-Strengthened Austenitic Stainless Steel (Type 304N) |
|---|---|
| UNS Designation | S30451 |
| Microstructure | Austenitic (Nitrogen-Stabilized) |
| Magnetic State | Non-Magnetic (May show slight magnetism from cold-working) |
| Density | ~8.00 g/cm³ (0.289 lb/in³) |
| Size Range | Metric: M6 to M100 | Imperial: 1/4" to 4" Custom oversized nuts available upon request. |
| Thread Types | UNC, UNF, 8UN, Metric Coarse, Metric Fine |
| Strengthening Method | Nitrogen Solid-Solution Strengthening |
■ Proprietary Datasheet Download (GATED)
Access professional-grade technical data for ASTM A194 Grade 8N, including nitrogen-enhanced yield thresholds, dimensional standards, and mating bolt torque charts.
ASTM A194 Grade 8N — Complete Technical Datasheet
Contains detailed proof load thresholds, dimensional tolerances for ASME B18.2.2 standard and heavy hex profiles, and precise galling-prevention torque values for A193 B8N assemblies.
⬇ DOWNLOAD DATASHEET■ MTC Integration Section
Material traceability is the backbone of safety in high-pressure, severe-corrosion environments. Every lot shipped by Ananka is accompanied by fully authenticated documentation mapping back to raw steel mill certificates.
- EN 10204 Type 3.1: Issued by our independent quality department, providing specific heat-traceable test results (actual chemical analysis verifying Nitrogen limits, mechanical test results, hardness, and proof load tests).
- EN 10204 Type 3.2: For critical cryogenic, offshore, or nuclear applications, we facilitate third-party witness testing.
■ Chemical Composition
| Carbon (C) | Manganese (Mn) | Chromium (Cr) | Nickel (Ni) | Nitrogen (N) | Phosphorus (P) | Sulfur (S) | Silicon (Si) |
|---|---|---|---|---|---|---|---|
| 0.08 Max | 2.00 Max | 18.00 – 20.00 | 8.00 – 11.00 | 0.10 – 0.16 | 0.045 Max | 0.030 Max | 1.00 Max |
■ Mechanical Properties
| Mechanical Property | Grade 8N Limits |
|---|---|
| Proof Load Stress (Heavy Hex) | 80 ksi (550 MPa) |
| Proof Load Stress (Standard Hex) | 75 ksi (515 MPa) |
| Hardness Limit (Rockwell) | 60 HRB to 32 HRC |
| Hardness Limit (Brinell) | 126 to 302 HBW |
■ Compatible Fastener Assemblies
| Internal Threads (A194 Gr 8N) | Mating Bolts (A193 Gr B8N) | Mating Studs (A193 Gr B8N) |
|---|---|---|
| Grade 8N Heavy Hex Nuts | ASTM A193 Grade B8N Hex Bolts | A193 Grade B8N Fully Threaded Studs |
■ Torque & Installation Guidelines
| Nominal Diameter | Threads Per Inch (UNC) | Target Torque — Lubricated (ft-lbs) |
|---|---|---|
| 1/2" | 13 | 30 |
| 5/8" | 11 | 60 |
| 3/4" | 10 | 100 |
| 1" | 8 | 250 |
