304 & 304L Stainless Steel Threaded Rods
304 and 304L stainless steel threaded rods are widely used for threaded connections where good general corrosion resistance, clean appearance and reliable mechanical performance are required. The 304 grade combines chromium and nickel to provide resistance to moisture and many common atmospheric and industrial environments, while remaining well suited to forming and general fabrication. 304L has a lower carbon content, making it a useful choice for assemblies that involve welding or other thermal processes.
With continuous threads along the rod, these fasteners can be cut to the required length and paired with nuts, washers, couplers and other threaded components. They are used in equipment assembly, pipe and mechanical installations, supports, fabrication projects and other applications where the fastening length may need to be adjusted on site. We supply 304 and 304L threaded rods in metric and inch sizes, with different thread and length options available to match the requirements of the assembly.
Dimension Standard:
The dimensions of 304 and 304L stainless steel threaded rods need to match the nuts, couplers and other threaded parts used in the assembly. Depending on the market and application, the rods may be supplied to different metric or inch dimensional systems, with variations in nominal diameter, thread pitch, length and thread designation.
DIN 975, DIN 976 and ASME B18.31.3 are the dimensional references covered on this page. The following sections explain the characteristics of each standard and help identify the appropriate 304 or 304L threaded rod for a specific threaded connection.
Chemical Composition:
The material composition of 304 and 304L stainless steel threaded rods is based on a chromium-nickel stainless steel system, with controlled amounts of carbon, manganese, silicon and other alloying elements. Chromium provides the basic stainless steel character, while nickel contributes to the material’s structure and overall performance. The main difference between 304 and 304L is the carbon limit: 304L contains less carbon, which helps reduce carbide precipitation during welding and other heat-intensive fabrication processes.
| Material | Carbon(C) | Chromum(Cr) | Manganesse(Mn) | Nickel(Ni) | Silicon(Si) | Phosphorus(P) | Sulfur(S) | Nitrogen(N) |
| 304 Stainless Steel | ≤0.08% | 18-20% | ≤2% | 8-10.5% | ≤1% | ≤0.045% | ≤0.03% | ≤0.01% |
| 304L Stainless Steel | ≤0.03% | 18-20% | ≤2% | 8-10.5% | ≤1% | ≤0.045% | ≤0.03% | ≤0.01% |
Mechanical Property:
304 and 304L stainless steel threaded rods can be supplied with different mechanical property designations depending on the fastener standard and grade specified for the application. The stainless steel grade identifies the material, while the applicable fastener standard establishes the required tensile strength, proof or yield strength, elongation and other mechanical requirements. ISO 3506-1, ASTM F593 and ASTM A193 B8 use different designation systems and requirements. The sections below show how these standards classify and specify the mechanical performance of stainless steel threaded rods, allowing the required strength level to be matched with the intended assembly.
Mechanical Property of 304 & 304L Metric Bolts according to ISO3506-1
| Item | Property Class | Tension Strength(min)MPA | Stress at 0.2% non-proprotional elongation(min)MPA | Elongation after fracture(min)mm |
| 304 & 304L Stainless Steel Metric Bolts | A2-50 | 500 | 210 | 0.6d |
| A2-70 | 700 | 450 | 0.4d | |
| A2-80 | 800 | 600 | 0.3d |
Mechanical Property of 304 & 304L Inch Bolts according to ASTM F593
| Item | Grade | Diameter,in | Full-Size Tests | Machine Specimen Test | ||||
| Tensile Strength (ksi) | Yield Strength (ksi) | Rockwell Hardness | Tensile Strength (ksi) | Yield Strength (ksi) | Elongation in 4D,% | |||
| 304 & 304L Stainless Steel Inch Bolts | F593C | 1/4"-5/8" | 100-150 | 65 | B95-C32 | 95 | 60 | 20 |
| F593D | 3/4"-1"-1/2" | 85-140 | 45 | B80-C32 | 80 | 40 | 25 | |
| F593C | 1-1/8"-1-1/4" | 100-140 | 60 | B95-C30 | 95 | 55 | 20 | |
| F593D | 1-1/8"-1-1/2" | 95-130 | 45 | B90-C28 | 90 | 40 | 28 | |
Mechanical Property of 304 & 304L Inch Bolts according to ASTM A193 B8
| Mechanical Requirements, Inch Products | |||||||
|---|---|---|---|---|---|---|---|
| Class | Diameter | Tensile Strength, min, ksi | Yield Strength, min, ksi | Elongation in 4D min, % | Reduction of Area, min, % | Hardness, max | |
| B8 Class1 | All Diameters | 75 | 30 | 30 | 50 | 223 HBW | 96 HRB |
| B8 Class2 | Up to 3/4 | 125 | 100 | 12 | 35 | 321 max | 35 HRC max |
| 7/8 - 1 | 115 | 80 | 15 | 35 | |||
| 1-1/8 - 1-1/4 | 105 | 65 | 20 | 35 | |||
| 1-3/8 - 1-1/2 | 100 | 50 | 28 | 45 | |||