Overview
AISI 321H tubes has good forming and welding capabilities, and is widely used in running temperature atmospheres. It was developed for enhanced creep resistance and for higher strength at temperatures above 1000 Deg F (537 Degree C). AISI 321H Tubes resists oxidation to 1500 Degree F (816 Degree C) and has higher creep and stress rupture properties than alloys 304 and 304L. High-temperature materials are optimized for strength and corrosion resistance at elevated temperatures, the resistance to electrochemical low-temperature corrosion of Alloy 321H Pipes may be less satisfactory. Type 321H Pipes is non-magnetic in the annealed condition and can be hardened only by cold working.
321H Seamless Tubes does not work well in sulphuric acid, small concentrations, or even in chloride solutions. It should be used for applications needing alternating heating between 850 degrees F and 1600 degrees F. The tube which of high-temperature corrosion resistance is similar to the grade SS304, which cannot be toughened by heat treatment and can be finished only by cold working.
Specification
ASTM A213/A213M-21a Standard Specification for Seamless Ferritic and Austenitic Alloy-Steel Boiler, Superheater, and Heat-Exchanger Tubes.
| Specifications | ASTM A213 / ASME SA213 |
| Dimensions | ASTM, ASME and API |
| Range | 1/2"OD - 12"OD |
| Outside Diameter | 3.00 mm - 219.10 mm, 6.35 mm O.D to 114.3 mm O.D |
| Length | Single Random, Double Random & Required Length |
| Thickness | 0.40 mm - 12.70 mm, 0.8 mm to12.7 mm |
| Schedule | SCH20, SCH30, SCH40, STD, SCH80, XS, SCH60, SCH120, SCH140, SCH160, XXS |
| Type | Seamless |
| Form | Round Tube, Square Tube, Rectangular Tube |
| End | Plain End, Beveled End, Treaded |
ASTM A213 SS 321H Equivalent
Grade | UNS No | Old British | Euronorm | Swedish SS | Japanese JIS | ||
| BS | En | No | Name | ||||
| 321H | S32109 | 321S51 | – | 1.4878 | X10CrNiTi18-10 | – | SUS 321H |
Chemical Composition
| Grade | C | Mn | Si | P | S | Cr | N | Ni | Ti |
| SS 321H | 0.04 – 0.10 | 2.0 max | 1.0 max | 0.045 max | 0.030 max | 17.00 - 19.00 | 0.10 max | 9.00 – 12.00 | 4(C+N) – 0.70 max |
Mechanical Properties
Grade | Tensile Strength | Yield Strength | Elongation | Hardness | |
| Rockwell B (HR B) max | Brinell (HB) max | ||||
| 321H | 515 | 205 | 40 | 95 | 217 |
Physical Properties
Grade | Density | Elastic Modulus | Mean Co-eff of Thermal Expansion (µm/m/°C) | Thermal Conductivity (W/m.K) | Specific Heat 0-100°C (J/kg.K) | Elec Resistivity (nΩ.m) | |||
| 0-100°C | 0-315°C | 0-538°C | At 100°C | At 500°C | |||||
| 321H | 8027 | 193 | 16.6 | 17.2 | 18.6 | 16.1 | 22.2 | 500 | 720 |
Applications
- 1. Food preparation equipment particularly in chloride environments.
- 2. Laboratory benches & equipment.
- 3. Coastal architectural panelling, railings & trim.
- 4. Boat fittings.
- 5. Chemical containers, including for transport.
- 6. Heat Exchangers.
- 7. Woven or welded screens for mining, quarrying & water filtration.
- 8. Threaded fasteners.
- 9. Springs.
