Design surface Type LP and HP heater should be described with reference to sectional arrangement drawings. These drawings should be representative in terms of heater disposition, channel division plate details, baffling arrangements, the location of any de-superheating and drain cooling sections arid their shrouding, etc.
The design surface Type LP and HP heater must be performed by manufacturer which has relevant and successful experience with the type of heaters being proposed. Heaters are required to last the life of the station with minimal maintenance. The design surface Type LP and HP heater should therefore describe the design features incorporated into the design of the feed water heaters to minimize or eliminate problems of:
- Tube vibration and corrosion
- Tube fretting at baffles and shroud plates
- Tube erosion and fretting adjacent to bled steam and flash drain inlets
- Distortion and cracking at the tube plate
- Stagnant pockets of non-condensable gases.
- Division plate cracking and damage