Directing against the problems existing on heating surface in boiler of 300 MW unit

such as over-temperature in long or short time

worsening of material's behavior

failure of weld-joints between different steels

as well as wall entrance tubes' seal

worn-out

and corrosion etc.

analysis has been carried out respectively

and preventive and repair measures

i.e.preventing foreign matters lead to blockage

avoiding direct welding on sealing protective plate of the furnace wall and on heating surface tubes

liquidating deposited ash to prevent worn-out and corrosion etc.

being put forward.