Pre-Operation Safety Inspections
Before starting any industrial dryer, operators must conduct a thorough inspection of all critical process points and equipment. This includes verifying that all gearboxes and transmission parts are sufficiently lubricated, checking belt tension, and ensuring the audible and visual alarm systems are functioning normally. The hot air chamber overheat alarm and all safety temperature monitoring instruments must be verified. Lightning protection grounding devices should be properly connected, and mechanical equipment bases must be stable. All bolted connections and welded joints should be confirmed firm and reliable. Operating platforms, stairway guardrails, and anti-slip steel plates must be secure. Additionally, inspect the protective mesh covers on heat exchanger cold air intakes, check power cables for corrosion, and verify electrical equipment grounding protection and insulation conditions.
In-Operation Monitoring Requirements
During drying operations, operators must closely monitor equipment operation and address any abnormal conditions immediately. Key monitoring points include checking for material blockages at prone locations, verifying conveyor belt alignment stays within allowable limits, and ensuring motor and gearbox surface temperatures remain within specified ranges. Watch for loose flange connections causing dust leakage, blockages in air ducts and chutes, and cracks or leaks in hot air ducts. Monitor equipment current and voltage readings, listen for unusual sounds or odors, and verify that post-drying product output, moisture content, and quality meet requirements. Production should only resume after all issues are resolved.
Safe Operating Procedures and Interlock Systems
The fundamental principle for industrial dryer operation is reverse process flow for startup (start downstream equipment first) and forward process flow for shutdown (stop upstream equipment first). During faults, equipment upstream of the fault point stops immediately while downstream equipment stops sequentially after complete discharge. The electrical control panel must provide both interlock and interlock release functions. Critical interlock relationships include dryer material level with infeed conveyors, furnace chamber temperature with the hot air blower, and the induced draft fan with the blower. The recommended startup sequence is: furnace ignition, grain loading, grain discharge, hot air fan activation, furnace temperature ramp-up, process parameter adjustment, then normal production.
Shutdown Procedures by Duration
For temporary shutdowns under 20 hours, stop equipment before the fault point, cease feeding, and turn off the blower. When flue gas temperature drops below 300 degrees Celsius, turn off the induced draft fan and hot air fan. After shutdown, discharge material for 20 to 30 minutes every 2 hours to prevent bridging. During power outages, immediately open all furnace doors and cold air dampers for natural ventilation. For extended shutdowns of 20 hours to 10 days, follow specific cooldown protocols. For end-of-season shutdowns exceeding 10 days, sequentially shut down all equipment, extinguish the furnace completely, thoroughly remove all debris from inside the dryer, and run cold air fans to ensure complete cleaning.
Personnel Safety Regulations
All personnel must complete safety technique and operating procedure training before starting work. Operators must wear proper safety protective equipment including anti-slip gear and falling object protection. Electrical safety procedures must be strictly followed, and non-electricians are forbidden from performing electrical work. Fire safety regulations must be observed when using fire on site. Alcohol consumption during shifts is strictly prohibited. Troubleshooting or removing faults while machinery is running is forbidden. Night operations require adequate lighting. Warning signs must be clearly visible on all moving screens, fan inlets and outlets, and high-speed rotating mechanisms.
