Mae ASTM A269 yn fanyleb safonol ar gyfer tiwbiau dur di-staen austenitig di-dor ac wedi'u weldio ar gyfer gwasanaethau cyffredinol sy'n gwrthsefyll cyrydiad a thymheredd isel neu uchel. Mae ASTM A249 yn fanyleb safonol ar gyfer boeler dur austenitig weldio, superheater, cyfnewidydd gwres, a thiwbiau cyddwysydd. Mae ASTM A213 yn fanyleb safonol ar gyfer boeler aloi-dur di-dor ferritig ac austenitig, superheater, a thiwbiau cyfnewidydd gwres. Mae'r gwahaniaethau rhwng A269, A249, ac A213 yn gorwedd yn y safonau penodol y maent yn eu cynrychioli ar gyfer tiwbiau dur di-staen.
SAFON ASTMA249 ASTM A269 ASTMA270 ASTM213
| Safonol | Goddef Diamedr Allanol (mm) | Trwch wal(%) | Goddefgarwch Hyd(mm) | ||
| ASTM A249 | <25.0 | +0.10 -0.11 | ±10% | ||
| ≥25.0-≤40.0 | ±0.15 | ||||
| >40.0-<50.0 | ±0.20 | OD<50.8 | +3.0-0.0 | ||
| ≥50.0~<65.0 | ±0.25 | ||||
| ≥65.0-<75.0 | ±0.30 | ||||
| ≥75.0~<100.0 | ±0.38 | OD≥50.8 | +5.0-0.0 | ||
| ≥100 ~ ≤200.0 | +0.38 -0.64 | ||||
| >200.0-≤225.0 | +0.38 -1.14 | ||||
| ASTM A269 | <38.1 | ±0.13 | |||
| ≥38.1~<88.9 | ±0.25 | ||||
| ≥88.9-<139.7 | ±0.38 | ±15.0% | OD <38.1 | +3.2-0.0 | |
| ≥139.7~<203.2 | ±0.76 | ±10.0% | 0D ≥38.1 | +4.0-0.0 | |
| ≥203.2-<304.8 | ±1.01 | ||||
| ≥304.8-<355.6 | ±1.26 | ||||
| ASTMA270 | ≤25.4 | ±0.13 | ±10% | +10-0.0 | |
| >25.4-≤50.8 | ±0.20 | ||||
| >50.8~≤62 | ±0.25 | ||||
| >76.2- ≤101.6 | ±0.38 | ||||
| >101.6~<139.7 | ±0.38 | ||||
| ≥139.7–203.2 | ±0.76 | ||||
| ≥203 2~≤304.8 | ±1.27 | ||||
| ASTM213 | D＜25.4 | ± 0.10 | +20/0 | +3.0/0 | |
| 25.4~38.1 | ±0.15 | ||||
| 38.1 ~ 50.8 | ±0.20 | ||||
| 50.8 ~ 63.5 | ±0.25 | +22/0 | +5.0/0 | ||
| 63.5 ~ 76.2 | ±0.30 | ||||
| 76.2 ~ 101.6 | ±0.38 | ||||
| 101.6 ~ 190.5 | +0.38/-0.64 | ||||
| 190.5~228.6 | +0.38/- 1.14 | ||||
Amser postio: Mehefin-27-2023