Fan Bearing Grease Quantity Calculator

G = 0.005 × D × B grams. The defaults model a 22310 spherical roller in a fan plummer block (OD 110 mm, width 40 mm → 22 g) — measure or look up your bearing's OD and width and the tool recomputes instantly. This is the replenishment charge, not the initial fill (which is 30–50% of the free space for most speeds).

A short spike is physics (fresh grease churning and purging — settles in 30–60 min); a persistent rise is a mistake: too much quantity, blocked relief path, or incompatible thickener stiffening in place. Verify with this calculator's grams (large rollers feel like they want more — they don't), make sure old grease can exit (clean the relief port), and check compatibility if the grease brand changed. If temperature stabilises above the pre-greasing baseline, purge the housing properly at the next stop.

The rolling elements churn through excess grease, temperature climbs sharply (often 10–30 °C), the thickener shears down and bleeds oil, and pressure can lip the seals open — after which contaminants walk in. Electric motors suffer the extra failure mode of grease forced into the windings. If you see grease purging from seals and a temperature spike after lubing, you found the cause.

Interval depends on speed factor (n·dm), temperature, load and orientation — use the OEM's table or SKF's relubrication chart as your starting point, then halve it for every 15 °C the bearing runs above 70 °C, for vertical shafts, or for wet/dusty service. Enter that interval here and pair this tool with a bearing-temperature trend to validate it.