四、 Classified by boiler outlet working pressure
1. Low pressure boiler: general pressure is less than 1.275MPa;
2. medium pressure boiler: general pressure is 3.825MPa;
3. high pressure boiler: general pressure is 9.8MPa;
4. ultra high pressure boiler: general pressure is 13.73MPa;
5. subcritical Pressure boiler: general pressure is 16.67MPa;
6. supercritical pressure boiler: general pressure is 22.13MPa.
