In a grease-lubricated bearing, the desirable behavior where the rolling elements cut a path through the grease and push it to the sides, where it stays as a reservoir and seal and bleeds oil back to the track. Channeling greases run cool, while non-channeling greases slump back into the path, churn and run hot. In cold gear oils the same word means the bad case: oil so thick the gear cuts a groove through it and picks nothing up.
Bearing's running hot because that grease won't channel, it keeps slumping back into the balls and churning.
Also heard as
- channelling
Related terms
Overgreasing
Pumping more grease into a bearing than it needs, causing churning, heat and blown seals.
Bleed
Separation of oil from a grease, either as a storage problem or as the intended release of oil to a bearing.
NLGI grade
Number from 000 to 6 describing grease stiffness, based on cone penetration after working.
Running hot
Shop phrase for a bearing, gearbox or motor operating above its normal temperature.