High-Temperature Component Maintenance for Veneer Dryer

High-Temperature Component Maintenance & Detailed Cycles 

1. Special Maintenance for High-Temperature Zones

Components in high-temperature zones (e.g., roller bearings near the heating chamber, furnace grates) are exposed to prolonged high temperatures (often exceeding 200°C), making lubrication critical.

- Lubricant Requirement: Must use high-temperature resistant grease. High-temperature resistant grease maintains its lubricity and structural stability under high temperatures, preventing melting, carbonization, or loss that would expose metal surfaces to direct friction.

- Temporary Substitution: If high-temperature resistant grease is unavailable, ordinary grease can be used temporarily. However, this is only a short-term solution—once high-temperature resistant grease is procured, replace the temporary grease immediately. Prolonged use of ordinary grease in high-temperature zones will lead to rapid degradation, increasing wear and failure risks.

2. Bearing Lubrication Specifications

Bearings are key rotating components, and their lubrication quantity directly affects performance. The following rules must be followed:

- Sealed Bearings: Fill with 20%–30% grease of the inner cavity volume. Overfilling will cause excessive pressure, leading to grease leakage and increased rotational resistance.

- Low-Speed Bearings: It is recommended to fill the inner cavity completely. Low-speed operation generates less heat, and full filling ensures continuous lubrication between rolling elements and raceways.

- Medium-Speed Bearings: Fill 1/2–1/3 of the inner cavity volume. This balance reduces heat buildup from grease churning while providing sufficient lubrication.

- High-Speed Bearings: Do not exceed 1/3 of the inner cavity volume. High-speed rotation causes intense grease agitation; excessive grease will increase friction and temperature, accelerating grease degradation.

- Open Bearings: Fill 30%–50% of the inner cavity volume. Open bearings are exposed to dust and debris, and moderate filling prevents contaminants from entering while maintaining lubrication.

3. Detailed Maintenance Cycles

Regular maintenance at specified intervals is crucial to prevent unexpected failures. The cycles are determined based on daily operating hours and component characteristics:

- Reducer Gear Oil

- Initial maintenance: For equipment operating 10 hours/day, replace gear oil after 6 months; for 20 hours/day, replace after 3 months. Initial operation causes metal debris from running-in, which must be removed through oil replacement.

- Subsequent maintenance: Replace gear oil once a year, regardless of daily operating hours, to ensure lubrication efficiency.

- Exposed Friction Components (Gears, Chains):

- Generally, lubricate once a week. These components are exposed to dust and external environments, and friction increases rapidly without timely lubrication. If "metal-on-metal" friction (audible grinding sounds or visible wear) is observed, lubricate immediately, regardless of the schedule.

- Roller Bearings & Belt Bearings:

- For bearings in normal temperature zones: Lubricate once a month.

- For bearings in high-temperature zones: Shorten the cycle to once every half a month due to accelerated grease degradation under heat.