Troubleshooting and maintenance tips for chain grates and cross-beam grates

Faults on chain grates and cross-beam grates concentrate on the grate bars, pins and chains. Correct handling and maintenance can avoid most unplanned downtime.

Common faults and remedies

When a grate bar breaks or a pin falls out, the bars press on each other and jam. After long service, grate bars under high temperature and mechanical stress tend to fracture. For handling, stop the boiler and check where the break is, replace the broken bar and the lost pin, and confirm that the neighbouring bars sit level. A loose or broken chain is also fairly common: check the tension regularly and adjust the tensioning device so that the chain keeps suitable tension; when the chain has already broken, fit a new chain and make sure it is installed correctly and meshes well with the sprockets.

Maintenance practice

Check grate bars, pins and chains regularly for wear and looseness, and deal with any problem promptly. Chains, sprockets and bearings need regular lubrication with high-temperature grease chosen as the equipment requires, generally once a week, with more frequent application under high temperature or heavy load. When lubricating, apply the lubricant evenly to the points that need it and avoid excess running into the furnace.

After every shutdown, clear ash and unburned fuel from the grate in good time, using a scraper, brush or similar tool to work the ash out from between the bars. Clean the grate air boxes regularly so that dust and debris do not block the air ports and reduce the ventilation effect.