Common Standard Sizes for Stainless Steel Threaded Rod
1. Metric Series (Most popular for domestic & European market)
Diameter: M3 / M4 / M5 / M6 / M8 / M10 / M12 / M14 / M16 / M18 / M20 / M24 / M27 / M30
Standard finished lengths: 1m, 2m, 3m; custom cut-to-length available upon request.
2. UNC / UNF Inch Series (American standard, US & Southeast Asia market)
1/4″-20UNC, 5/16″-18UNC, 3/8″-16UNC, 1/2″-13UNC, 5/8″-11UNC, 3/4″-10UNC, 7/8″-9UNC, 1″-8UNC Standard bar length: 3ft, 6ft, 1m, 2m, 3m.
3. Key Regular Size Classification for Bulk Production
Small specification (Decoration & electrical fitting): M3~M6
Medium specification (Construction, pipeline fixing, mainstream): M8~M16 (largest consumption)
Large specification (Heavy machinery, pressure equipment): M18~M30
Main Grades: 304, 316L, 201, 310S
1. Grade 304 (UNS S30400, 1.4301, 06Cr19Ni10)
Chemical Composition (wt%)
C≤0.08, Cr:18.00–20.00, Ni:8.00–11.00, Mn≤2.00, Si≤1.00, P≤0.045, S≤0.030, Fe balance.
Physical & Mechanical Properties (annealed)
Tensile ≥520MPa, Yield ≥205MPa, Elongation≥40%, HB≤201; density 7.93g/cm³; nearly non-magnetic after annealing, slight magnetism after thread rolling.
Advantages
Cost-effective general-purpose grade; good atmospheric & fresh-water corrosion resistance; easy thread rolling, machining and welding; most widely used for indoor & dry outdoor fastening.
2. Grade 316L (UNS S31603, 1.4404, 022Cr17Ni12Mo2)
Chemical Composition (wt%)
C≤0.03, Cr:16.00–18.50, Ni:10.00–14.00, Mo:2.00–3.00, Mn≤2.00, Si≤1.00, P≤0.045, S≤0.030, Fe balance.
Physical & Mechanical Properties (annealed)
Tensile ≥485MPa, Yield ≥170MPa, Elongation≥40%, HB≤201; density7.98g/cm³;
low carbon avoids intergranular corrosion after welding.
Advantages
Added molybdenum delivers outstanding chloride resistance; superior anti-rust performance in coastal, seawater, mild acid & chemical environments; ideal for marine, chemical, sewage & outdoor corrosive conditions.
3. Grade 201 (UNS S20100, 1Cr17Mn6Ni5N)
Chemical Composition (wt%)
C≤0.15, Cr:16.00–18.00, Ni:3.50–5.50, Mn:5.50–7.50, N≤0.25, Si≤1.00, P≤0.060, S≤0.030, Fe balance.
Physical & Mechanical Properties (annealed)
Tensile≥520MPa, Yield≥275MPa, Elongation≥40%; slight magnetic after cold forming.
Advantages
Low-nickel high-manganese formula with much lower cost than 304; decent rust resistance for dry indoor decoration & non-corrosive general fixing projects.
4. Grade 310S (UNS S31008,1.4845,06Cr25Ni20)
Chemical Composition (wt%)
C≤0.08, Cr:24.00–26.00, Ni:19.00–22.00, Mn≤2.00, Si≤1.50, P≤0.045, S≤0.030, Fe balance.
Physical & Mechanical Properties (annealed)
Tensile≥520MPa, Yield≥205MPa, Elongation≥40%, HB≤201; excellent high-temperature structural stability.
Advantages
Premium high-temperature resistant grade; continuous service up to 1000℃; outstanding oxidation & high-temperature flue gas corrosion resistance; used for high-temperature furnace, boiler & heat equipment fastening.
Brief Selection Tip
- Indoor common installation → 304
- Coastal/chemical/marine environment →316L
- Dry indoor low-cost decoration →201
- High-temperature working condition →310S
