Stainless Steel 304H Seamless Pipes & Tubes
SS 304H (UNS S30409) is the high-carbon version of 304, with carbon controlled to 0.04-0.10%. This higher carbon content provides significantly improved creep strength and rupture properties at temperatures between 425-816C, making it the preferred grade for boiler, superheater, and heat exchanger applications in power generation and petrochemical industries.
Size Range
1/4" NPS to 10" NPS (6.35mm to 273.1mm OD)
Wall Thickness
SCH 5S to SCH 160, XXS
Standards
4 specs
Chemical Composition (% by weight)
| C | Mn | Si | Cr | Ni | P | S |
|---|---|---|---|---|---|---|
| 0.04-0.10 | 2.00 max | 0.75 max | 18.0-20.0 | 8.0-10.5 | 0.045 max | 0.030 max |
Mechanical Properties (Minimum at Room Temperature)
| Tensile Strength | Yield Strength | Elongation | Hardness |
|---|---|---|---|
| 515 MPa min | 205 MPa min | 35% min | 92 HRB max |
Physical Properties - SS 304H
| Density | Melting Range | Thermal Conductivity | Electrical Resistivity | Specific Heat | Coeff. of Thermal Expansion |
|---|---|---|---|---|---|
| 7.93 g/cm3 | 1400-1450 C | 16.2 W/m-K | 720 nOhm-m | 500 J/kg-K | 17.2 um/m-C |
Corrosion Resistance - SS 304H
| Property | Value |
|---|---|
| Pitting Resistance (PREN) | ~18 |
| Max Service Temp (Oxidizing) | 870 C (continuous) |
| Intergranular Corrosion | Susceptible if sensitized (higher carbon) |
| Stress Corrosion Cracking | Susceptible in chlorides >60C |
| General Corrosion Rate | <0.1 mm/yr in mild acids |
| Seawater Resistance | Limited - pitting risk |
Equivalent International Grades
| ASTM | JIS | BS | GOST |
|---|---|---|---|
| TP304H | SUS 304HTB | 304S51 | 08Kh18N10 |
SS 304H vs Comparable Grades
| Grade | UNS | Tensile | Yield | PREN | Max Temp |
|---|---|---|---|---|---|
| SS 304 / 304LAustenitic Stainless Steel | S30400 | 515 / 485 MPa min | 205 / 170 MPa min | ~18 | 870 C |
| SS 321Austenitic Stainless Steel | S32100 | 515 MPa min | 205 MPa min | ~17.5 | 900 C (continuous) |
| SS 316HAustenitic Stainless Steel | S31609 | 515 MPa min | 205 MPa min | ~24 | 870 C (continuous) |
Applicable Standards
Applications
Key Advantages of SS 304H
SS 304H Applications by Region
Middle East (UAE, Saudi Arabia, Qatar, Oman, Kuwait)
Used in refinery furnace tubes, power plant superheaters, and petrochemical cracking furnaces across UAE, Saudi Arabia, and Kuwait.
Europe (Germany, UK, Norway, Netherlands, Italy)
Specified for power generation boiler tubes and heat exchangers in Germany, UK, and Netherlands.
United States
Standard grade for power plant superheater and reheater tubes, and refinery high-temperature service.
Frequently Asked Questions about SS 304H Seamless Pipes
Quick Specifications
1/4" NPS to 10" NPS (6.35mm to 273.1mm OD)
SCH 5S to SCH 160, XXS
Industries Served
Related Grades
Ready to Order SS 304H Seamless Pipes?
Stancor is India's leading manufacturer of SS 304H seamless pipes, exporting to UAE, Saudi Arabia, Qatar, Germany, UK, and USA. Contact our sales team for competitive pricing, fast delivery, and full material certification.