The problems existing on fabric joints in return chute of two 300 MW CFB boilers in Datang Honghe Power Generation Co Ltd are overtemperature

burn-out of ring

and leakage etc.

the causes resulting in above-mentioned problems have been analysed

and retrofit scheme being put forward

including optimization of the sealing structure

adujustment of the reserved expansion clearance between the return chute and the furnace

and repair of abrasion-resistant refractory material inside the return chute etc..After retrofitting

the non-scheduled shutdown of units due to above-mentioned problems occurred on fabric expansion joints in return chute has been fundamentally resolved

enhancing safety and economic efficiency of the boilers.