HEI Standards for Steam Jet Vacuum Systems β’ ASME PTC 24
Understand ejector design principles, calculations, and industry applications
Designs steam jet ejectors per HEI Standards (5th Ed.) and ASME PTC 24 for vacuum systems, vapor recovery, and gas compression.
| Fluid | Ξ³ (k) | P*/Pβ | Notes |
|---|---|---|---|
| Steam (superheated) | 1.327 | 0.545 | Use k=1.135 for wet steam |
| Air / Nβ / Oβ | 1.40 | 0.528 | Diatomic gases |
| Natural Gas / CHβ | 1.31 | 0.544 | MW varies with composition |
| COβ | 1.30 | 0.546 | Triatomic |
Per HEI standards, motive steam should have quality β₯98% and superheat <50Β°F for optimal performance. Excessive superheat reduces entrainment capacity; wet steam causes erosion and performance loss.