How to Grease Bearings Correctly: A Step-by-Step Guide for Mechanics

The search query “how to grease bearings” sounds simple. In the field, this is where most lubrication programs fail — not because of “bad grease,” but because of dirty nipples, closed drains, and extra pumps “just in case.”

Before the first pump

1. Correct grease grade — the one in the asset datasheet or plant lube map. Do not mix “similar” tubs.
2. Clean gun and clean grease nipple. Dirt on the fitting goes straight into the raceway.
3. Open the drain when the housing design allows it. Without an exit path, new grease builds pressure.
4. Know the dose ceiling — formula or map value is a cap, not a target to empty the cartridge.

Step-by-step procedure

1. Clean the point

Wipe the nipple and surrounding area. One abrasive particle costs more than a minute with a rag.

2. Open the drain

Remove the drain plug or open the valve so old grease and excess can leave.

3. Add grease in small shots

Pump slowly, 1–2 strokes, then pause. Do not force the handle: gun pressure can reach hundreds of bar and blow a seal before you feel “resistance.”

4. Stop when “enough” shows up

Stop if fresh grease appears at the drain, temperature behavior is normal after running, or acoustic friction drops and stabilizes. If the formula ceiling is near and there is no stop signal — do not add “a little more.”

5. Close, clean, record

Refit the drain, wipe residue, log date, point, grease grade, and approximate volume.

Typical expensive mistakes

Mistake	Result
Calendar greasing with no check	Some points overfilled, others already dry
Closed drain	Seal blow-out, temperature rise
Mixing greases	Softening/hardening, dry contact
Dirty nipple	Abrasive wear
“One more pump for luck”	Churning, overheating, seal failure

See also over-greasing consequences and how often to lubricate.

How to know the dose without guessing

Q ≈ D × B × 0.005 (g, mm) is a starting ceiling. It does not know dust, temperature, or residual grease in the cavity. Mature plants use it as a limit and decide lubricate / skip / stop by condition.

Ultrasound hears friction rise earlier than temperature or classic vibration — see condition-based lubrication and grease quantity norms.

Where LUBExpert fits

Once the procedure is correct, the bottleneck is human variation across shifts. LUBExpert measures acoustic friction during greasing and shows the stop point — an objective “enough” for the whole route.

KEG TRK supplies LUBExpert and trains teams in Kazakhstan. Request a consultation.

Shift checklist

1. Right grade, clean nipple, open drain.
2. Small shots with pauses — never “to the stop.”
3. Stop at drain / acoustics / dose ceiling — whichever comes first.
4. Log the point.
5. If temperature rises after greasing — do not add more; investigate (often already over-greased).

Next: plant lubrication point map and what acoustic lubrication is.