The HEI Standards for Closed Feedwater Heaters (9th Edition) is the definitive industry manual for the design, construction, and operation of high-pressure and low-pressure shell-and-tube heat exchangers used to preheat boiler feedwater.
In a power plant cycle, these heaters use "extraction steam" from the turbine to warm up the water returning to the boiler. This significantly increases the overall thermodynamic efficiency of the plant. The 9th Edition (released in 2017) remains the current global benchmark for ensuring these massive components can withstand extreme pressures and thermal cycling.
Technical Scope & Content
Unlike a surface condenser (which operates under vacuum), a closed feedwater heater often operates at very high pressures. The HEI standard provides rigorous guidelines for:
Key Improvements in the 9th Edition
This edition introduced several critical updates to address common failure points in aging power plants:
| SDO | HEI: Heat Exchange Institute |
| Document Number | 2622 |
| Publication Date | Jan. 1, 2015 |
| Language | en - English |
| Page Count | 84 |
| Revision Level | 9 |
| Supercedes | |
| Committee |