Question details (Performance) :
Furnace wall cracks, deformation, coking, and tilt, loose bricks, partial loss, furnace tube wall was totally stuck and rock wool sealing is burned out, and combustion chamber wall is damaged.
Answer: Fault reason:
(1) Unreasonable furnace wall and arch structure, which hinders the expansion of boiler pressure parts.
(2) Improper combustion position, so that part of the furnace wall and arch temperature is too high and burn out, which makes deformation or collapse.
(3) When the furnace wall and arch oven are newly built, the furnace wall and the ash joints of the furnace arch are put into operation without thoroughly drying, just by short time heating and the rapid temperature rise.
(4) In operation, due to improper combustion adjustment, furnace is in long-term positive pressure combustion, which keeps high temperature in the furnace, if the ash melting point is low, the furnace is easy to coking. The furnace wall is badly burnt.
(5) The heating and stopping of the furnace and the increase or decrease of the load are too fast operated, causing the furnace wall and the furnace arch to expand or shrimp suddenly, and the furnace wall or the furnace arch will be damaged due to improper methods or excessive force when manually slagging.
(6) Improper proportion of mortar and wrong maintenance.
(7) Insufficient mortar between bricks. The bad quality of refractory makes furnace wall and arch are easy to burn and deform under the action of high temperature.
(8) When the boiler is in normal operation, if the air outside the furnace enters the furnace, the carbon dioxide content in the flue gas will be decreased, the oxygen content will be increased, the combustion chamber will be under positive pressure, and the boiler bracket or wall skin will be damaged.
(1) When the furnace wall is slightly cracked, it can be filled with rock wool rope and coated with refractory cement and rock wool mortar.
(2) When the furnace wall damage area is large, the temperature of boiler bracket or furnace wall abnormally is hot, boiler steel, hollow beam is burned into red color and furnace wall are in danger of collapse, in this case, the furnace must be immediately stopped and organize people to repair.
(3) If a small amount of refractory brick falls from the furnace wall, or exterior wall there was a slight bulge, monitoring and inspection should be strengthened to keep the short run and waiting for standby furnace start up boiler overhaul or plan.
(4) The furnace arch has a large damaged area and does not work in combustion. The furnace should be stopped immediately for repair or rebuild.
(5) If the damage area of furnace wall or hoist is small and not serious, the excess air coefficient in the furnace can be appropriately reduced, and the combustion temperature can be reduced to maintain a short time running.