For grease fills and grease life, the same information is valid for ball bearing units as it is for insert bearings.

Grease fills

Insert bearings are filled with one of the following greases (table 1):

  • bearings with zinc-coated rings and stainless steel bearings
    → food-grade grease GFM, registered by NSF as category H1
    The NSF registration confirms the grease fulfils the requirements listed in the US Food and Drug Administration's guidelines under 21 CFR section 178.3570 (lubricant acceptable with incidental food contact, for use in and around food processing areas).
    Additional certifications for the grease have been secured for use in halal and kosher food production processes.
  • all other bearings
    → standard grease VT307

Grease life for insert bearings

Grease life for insert bearings:
  • is presented as L10, i.e. the time period at the end of which 90% of the bearings are still reliably lubricated.
  • depends on the load, operating temperature and the ndm value (diagram 1)

The indicated grease life is valid for the following combination of operating conditions:

  • horizontal shaft
  • very light to moderate loads (P ≤ 0,05 C)
  • stationary machine
  • low vibration levels

Where the operating conditions vary, the grease life obtained from the diagrams should be adjusted as follows:

  • vertical shafts → 50% of the obtained value
  • heavier loads (P > 0,05 C) → apply reduction factor (table 2)

The values for adjusting the grease life are estimates. Vibration can have a negative influence on grease life. The extent cannot be quantified, and the influence increases with increasing operating temperature.

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