SS 304 Round Bars
Giriraj Impex is a manufacturer, stockist, supplier and exporter of SS 304 round bars and SS 304L round bars to ASTM A276 and ASTM A479 / ASME SA479, dual certified 304/304L where required. We manufacture SS 304 round bars in bright condition – peeled, turned, cold drawn or centreless ground – and in black condition, hot rolled or forged, together with hexagonal, square and flat bars, in random lengths or cut to length, with mill test certificates.
SS 304 round bar is the general-purpose stainless bar for shafts, fasteners, valve and pump parts, fittings and flanges machined from bar, and food, pharmaceutical and architectural components.
Specifications
| Item | Details |
|---|---|
| Standards | ASTM A276 (general use); ASTM A479 / ASME SA479 (boilers and pressure vessels); ASTM A484 general requirements |
| Grades | 304 (S30400), 304L (S30403), dual certified 304/304L; 304H on request |
| Condition | Annealed; cold drawn or strain hardened on request |
| Surface | Bright – peeled, turned, cold drawn, centreless ground, polished; black – hot rolled or forged |
| Tolerance | h9, h10, h11 for bright bars, or as specified |
| Shapes | Round, hexagonal, square, flat |
| Length | Random lengths or cut to length |
| Testing | Ultrasonic test, IGC test to ASTM A262 Practice E on request |
| Documents | Mill test certificate (MTC); third-party inspection on request |
Mechanical properties
| Grade | Tensile strength, MPa (ksi) | Yield strength, MPa (ksi) | Elongation in 50 mm, % | Reduction of area, % |
|---|---|---|---|---|
| 304 | 515 (75) | 205 (30) | 30 | 40 |
| 304L | 485 (70) | 170 (25) | 30 | 40 |
| 316 | 515 (75) | 205 (30) | 30 | 40 |
| 316L | 485 (70) | 170 (25) | 30 | 40 |
Chemical composition as given in ASTM A479 / A276 for each grade.
The composition of 304 and 304L bar is essentially the same as for other 304 products; the limits for each standard are on the SS 304 / 304L page, and the actual analysis on the mill test certificate.
A276 or A479?
ASTM A276 covers stainless steel bars for general use, such as machined parts, shafts and fasteners. ASTM A479 covers bars for boilers and pressure vessels, with additional requirements for mechanical testing and heat treatment, and is the standard to specify when the bar will be machined into pressure-retaining parts such as flanges, fittings or valve bodies. Many bars are certified to both standards.
Bright bars and tolerances
Bright SS 304 bars are peeled or turned to remove the hot-rolled skin, then straightened and, for close tolerances, centreless ground and polished. They are ready for machining with minimal stock removal and are used directly for shafts and pins. Cold-drawn bars have a smooth surface, close tolerance and higher strength from cold work. Black bars are used where the bar will be fully machined or forged. Please give the tolerance class – h9 for precision ground bar, h10 or h11 for turned or peeled bar – and any straightness requirement.
How we manufacture SS 304 round bars
We manufacture SS 304 round bars from certified billets and wire rod by hot rolling or forging, followed by solution annealing and pickling. Bright bars are then peeled, turned, drawn or ground to size, straightened and cut to length. Every bar is marked with grade and heat number, and diameter, straightness and surface are inspected before dispatch. Ultrasonic testing is carried out on request for bars that will be machined into pressure parts.
Machining and use
304 work-hardens during machining, so use sharp tools, positive rake and continuous feeds. Where free machining is important and corrosion resistance can be slightly lower, grade 303 is an alternative. For welded parts, 304L avoids sensitisation. In chloride-bearing or marine environments, choose SS 316 round bars instead.
Ordering SS 304 round bars
Please give the grade and standard, shape and size, tolerance, condition and surface, length, quantity and any testing or inspection requirement. Bars are bundled or boxed, bright bars wrapped to protect the finish, and each bundle is tagged with grade, size and heat number.
Applications and related products
SS 304 round bars are used for shafts, spindles and pins, bolts, studs and nuts, valve stems and trim, pump parts, flanges and fittings machined from bar, food and dairy machinery, pharmaceutical equipment, architectural fittings and handrails. Other stainless grades are on the stainless steel round bars page and other materials on the round bars, rods and wires page. In the same grade we also supply SS 304 pipes and SS 304 sheets and plates.
Frequently Asked Questions
ASTM A276 covers stainless bars for general use and ASTM A479 (ASME SA479) covers bars for boilers and pressure vessels. Many bars are certified to both.
304L has a lower maximum carbon content, which avoids sensitisation during welding. Bars are often dual certified 304/304L.
A bright bar has been peeled, turned, cold drawn or ground to remove the hot-rolled skin, giving a clean surface and close diameter tolerance.
SS 304 is non-magnetic when annealed, but cold-drawn bars can become slightly magnetic because of cold work.
Yes. SS 304 bars are supplied in round, hexagonal, square and flat shapes.
Yes. Bars are supplied in random lengths or cut to the lengths required.
Request a Quote for SS 304 Round Bars
Tell us the product, grade, size, standard, quantity and delivery location, and our sales team will reply with a quotation.