The grate is a core component of coal-fired and biomass boilers, responsible for feeding fuel and discharging ash and slag. If the grate malfunctions, it can prevent normal fuel feeding, lead to incomplete combustion, prevent the discharge of ash and slag, and cause the boiler to malfunction. Many people encounter grate malfunctions but don’t know how to handle them. Below, we’ll provide a detailed explanation of emergency response methods—be sure to read on.
Problem 1: The grate is jammed and won’t rotate. Symptoms include the grate failing to rotate normally, fuel piling up on the grate and failing to be conveyed, and incomplete combustion. Causes: Large debris (such as rocks or metal pieces) blocking the grate; loose or detached grate chains; worn or under-lubricated grate bearings; or a motor malfunction. Solution: Immediately shut down the furnace and cut off power to the grate; remove large debris from the grate; inspect the grate chain—if loose, tighten it promptly; if detached, reattach it immediately; inspect the grate bearings and replenish lubricant; if severely worn, replace them promptly; inspect the motor, repair any faults, restart the grate, and observe whether it returns to normal operation.
Fault 2: Grate deviation. This manifests as the grate shifting to one side during operation, causing friction with the furnace wall, producing abnormal noises, and potentially damaging the grate. Causes: Uneven tension in the grate chains, uneven wear on the grate rollers, and deformation of the guide rails on both sides of the furnace. Solution: Shut down the furnace and disconnect the power supply; adjust the tension of the grate chains to ensure they are equally tight on both sides; inspect the grate rollers and replace them promptly if they show uneven wear; inspect the furnace guide rails and repair any deformation immediately; adjust the grate position to ensure normal operation and prevent deviation.
Fault 3: Grate fracture or damage. Symptoms include broken or detached grate bars, fuel leakage, failure to properly discharge ash and slag, and impaired combustion. Causes: Prolonged use leading to severe component wear; impact from hard objects (stones, metal) in the fuel; substandard grate material. Solution: Immediately shut down the furnace; replace broken or damaged grate bars and tighten grate components; Remove any hard objects from the grate to prevent further impact; if the grate is severely damaged, replace the entire grate to ensure normal operation.
Fault 4: Abnormal grate speed. Symptoms include the grate rotating too fast or too slow, affecting fuel combustion and ash discharge. Causes: Abnormal motor speed, malfunctioning speed control mechanism, or excessive grate load. Solution: Shut down the furnace and disconnect power; check the motor speed and repair any motor faults; Inspect the speed control mechanism and adjust the grate speed to ensure it meets specifications; remove accumulated ash and debris from the grate to reduce the load and ensure normal grate speed.
Fault 5: Coal and ash leakage from the grate. This manifests as excessive gaps between grate bars, causing fuel and ash to leak out, which affects combustion efficiency and contaminates the boiler room environment. Causes: Wear or deformation of grate bars, excessive gaps between grate bars, or loose grate fastenings. Solution: Shut down the boiler, replace worn or deformed grate bars, adjust the gaps between grate bars, and tighten grate components to prevent coal and ash leakage; regularly clean accumulated ash and debris from the gaps between grate bars to ensure a good seal.
Note: When addressing grate malfunctions, you must first shut down the boiler and disconnect the power supply to ensure safety; wear appropriate protective gear when clearing debris or replacing parts to avoid burns; if you are unable to repair the issue yourself, contact professional maintenance personnel promptly to prevent equipment damage or safety incidents.
