In order to reduce the water-side pressure in high-pressure heaters

and decrease their number of leakage times

a tentative idea for enhancing the high-pressure heaters’ reliability for large-scale units has been put forward

changing the feed-water pump from connecting now on the inlet side of high-pressure heater No.3 to connecting on the outlet side of high-pressure heater No.1

making the feed-water after coming out from the pre-set feed-water pump to enter into high-pressure heater No.3

No.2

No.1 and the main feed-water pump consecutively

enabling the defferential pressure between steam side and water side of the said high-pressure heaters to be greatly lowered

and the leakage times to be decreased. At the same time

the problems may be encountered in realization of the said idea are discussed

and methods of their solution are given