Chemical Compositions
Grade | Mfg. Process | Chemical composition(%) | |||||||||
C | Si | Mn | P | S | Ni | Cr | Mo | Others | |||
St30Si | S | 0.10Max | 0.30Max | 0.55Max | 0.040Max | 0.040Max | - | - | - | - | |
St30A1 | S | 0.10Max | 0.05Max | 0.55Max | 0.040Max | 0.040Max | - | - | - | Al deoxydized | |
St35 | S | 0.17Max | 0.35Max | 0.40Max | 0.050Max | 0.050Max | - | - | - | - | |
St45 | S | 0.21Max | 0.35Max | 0.40Max | 0.050Max | 0.050Max | - | - | - | - | |
St52 | S | 0.22Max | 0.55Max | 1.60Max | 0.050Max | 0.050Max | - | - | - | - | |
Mechanical Properties(Mpa)
Grade | Material number | Tensile Test MPa or N/mm2 | Remaks (Similar to JIS) | Possibility Temperature | |
Min Yield point | Tensile Strength | ||||
St30Si | 1.0211 | - | 400Min | (STKM11) | |
- | 355Min | ||||
- | 285Min | ||||
215 | 295~420 | ||||
St30Al | 1.0212 | - | 400Min | (STKM11) | |
- | 355Min | ||||
- | 285Min | ||||
215 | 295~420 | ||||
St35 | 1.0308 | - | 440Min | (STC38) | |
- | 370Min | ||||
- | 315Min | ||||
235 | 340~470 | ||||
St45 | 1.0408 | - | 540Min | (STKM13) | |
- | 470Min | ||||
- | 390Min | ||||
255 | 440~570 | ||||
St52 | 1.0580 | - | 590Min | (STKM19) | |
- | 540Min | ||||
- | 490Min | ||||
350 | 490~630 | ||||
Delivery Condition
Term | Symbol | Explanation |
| Cold-finished/hard (cold-finished as-drawn) | BK | No heat treatment after the last cold-forming process. The tubes therefore have only low deformability. |
| Cold-finished/soft (lightly cold-worked) | BKW | After the last heat treatment there is a light finishing pass (cold drawing) With proper subsequent processing, the tube can be cold-formed (e.g. bent, expanded) within certain limits. |
| Annealed | GBK | After the final cold-forming process the tubes are annealed in a controlled atmosphere or under vacuum. |
| Normalized | NBK | The tubes are annealed above the upper transformation point in a controlled atmosphere or under vacuum. |
