Key Points for Daily Maintenance of DCY Gearboxes: Oil Change Cycle and Lubrication Standards

Oil change intervals: The first oil change should be performed after 300–400 hours of initial operation. Thereafter, replace the oil every 3,000–5,000 operating hours or once per year. In high-temperature, high-dust, or continuous heavy-duty environments, shorten the interval to within 2,000 hours.

Lubricant selection: Splash lubrication with natural cooling is the standard method. The recommended lubricant is medium-duty industrial gear oil (e.g., ISO VG 220 or ISO VG 320), with the specific viscosity grade chosen based on ambient temperature. The oil level should be maintained at the midpoint of the sight glass — too high causes churning and overheating, while too low results in insufficient lubrication.

Seal inspection: Regularly check shaft oil seals, housing joint faces, and drain plugs for leaks. Replace hardened or aged seals promptly to prevent oil leakage and dust ingress. Tighten housing joint bolts periodically and reapply sealant evenly if loosening is detected.

Gear and bearing inspection: Inspect gear tooth wear and pitting, as well as bearing noise and overheating, at least once every six months. Gears should be replaced when radial backlash exceeds 15% of the initial value. Bearing temperature should not exceed ambient temperature + 40°C.

Cooling system maintenance: For high-power models (DCY450 and above), cooling coils or forced oil circulation may be required when thermal capacity is insufficient. Clean dust from cooling surfaces regularly and verify that cooling lines are unobstructed. In sub-zero environments, preheat the lubricating oil to above 0°C before startup.

Breather maintenance: Keep the breather plug clear at all times. A blocked breather raises internal pressure, accelerating seal degradation and causing oil leaks.