ASTM A285 Steel Introduction:
ASTM A285 is a type of ordinary carbon steel intended for fusion-welded pressure vessel equipments as boiler, storage tank, heat exchangers, etc. With 3 steel grades (Grade A, Grade B, Grade C) covering tensile strength range from 310-515Mpa,usually ASTM A285 steel plate is delivered as-rolled condition. made by killed, semi-killed, capped or rimmed steel practices according to the end users' requirement.
ASTM A285 steel could be manufactured into many steel product forms, steel plates, steel coil, steel pipe, it has good weld-ability for fusion weld need for pressure vessel equipment, its max thickness is limited to 50mm in order to insure its mechanical property.
ASTM A283 Steel Introduction:
ASTM A283 is designed as a type of carbon steel plate for general structural purpose, this steel has low and intermediate tensile strength, it has 2 steel grades(Grade C, Grade D) . For steel plate made from coils or with no heat treatment, additional test is required for its stress relieving, usually after steel coil is decoiled, inspection, conditining, heat treatment are required before delivering. ASTM A283 is only used for structural purpose, while ASME SA283/SA283M steel plate could also be used in boiler and pressure vessel manufacture.
ASTM A285 Chemical Composition:
| ASTM A285 Chemical Composition | Grade A | Grade B | Grade C |
|---|---|---|---|
| Carbon, max | 0.17 | 0.22 | 0.28 |
| Manganese, max | 0.90 | 0.90 | 0.90 |
| Phosphorus, max | 0.035 | 0.035 | 0.035 |
| Sulphur, max | 0.035 | 0.035 | 0.035 |
ASTM A283 Chemical Composition:
| ASTM A283 Chemical Elements(max) | Heat Analysis, % | |
|---|---|---|
| Grade C | Grade D | |
| Carbon | 0.24 | 0.27 |
| Manganese | 0.90 | 0.90 |
| Phosphorus | 0.030 | 0.30 |
| Sulfur | 0.030 | 0.030 |
| Silicon | ||
| Plates 11⁄2 in. [40 mm] and under, max | 0.40 | 0.40 |
| Plates over 11⁄2 in. [40 mm] | 0.15-0.40 | 0.15-0.40 |
| Copper | 0.20 | 0.20 |
Mechanical Properties Comparision of ASTM A283 and ASTM A285
| Mechanical Property comparion of ASTM A283 and ASTM A285 | ||||||||
|---|---|---|---|---|---|---|---|---|
| Steel Grade | Tensile strength ,min Ksi Mpa | Yield strength min Ksi Mpa | Elongation in 2 inches (50 mm)% min. |
|||||
| ASTM A-36 / A-36 M | 58-80 ( 400-550 ) | 36 ( 250 ) | 23 | |||||
| ASTM A-283 / A-283 M gr A | 45-60 ( 310-415 ) | 24 ( 165 ) | 30 | |||||
| ASTM A-283 / A-283 M gr B | 50-65 ( 345-450 ) | 27 ( 215 ) | 28 | |||||
| ASTM A-283 / A-283 M gr C | 55-75 ( 380-515 ) | 30 ( 205 ) | 25 | |||||
| ASTM A-283 / A-283 M gr D | 60-80 ( 415-550 ) | 33 ( 230 ) | 23 | |||||
| ASTM A-285 / A-285 M gr A | 45-65 ( 310-450 ) | 24 ( 165 ) | 30 | |||||
| ASTM A-285 / A-285 M gr B | 50-70 ( 345-485 ) | 27 ( 215 ) | 28 | |||||
| ASTM A-285 / A-285 M gr C | 55-75 ( 380-515 ) | 30 ( 205 ) | 27 | |||||
A283 is a general low/intermediate strength structural steel, while A285 is specifically for fusion-welded pressure vessels, offering better high-temp performance (up to 900°F vs. 650°F for A283) with similar strength grades (A, B, C), making A285 superior for boilers and tanks. Key differences lie in their intended use (structural vs. pressure vessel), chemical composition controls, and maximum service temperatures, with A285 grades (A, B, C) generally having slightly better ductility.
