Cement industry
Grease classes for heavy, slow, dusty machines
Six grease families used in cement plants and similar heavy industry, what each is good at and where it fits.
Why NLGI 2
The families below are all NLGI 2. That grade is stiff enough to stay in a housing and soft enough to be pumped through a central system, which is why it dominates in automatic lubrication.
The families
| Grease class | Strengths | Where it fits |
|---|---|---|
| Lithium-calcium soap with solid lubricants and extremely high viscosity base oil | Protection under the harshest load, slow rotation and heavy vibration. Mechanically stable, water resistant, corrosion protective | Large spherical roller bearings under high load and slow rotation, where microslip is likely: crushers, mill and kiln rollers |
| High-viscosity calcium sulfonate complex | Excellent load capacity, oxidation and corrosion protection even with heavy water ingress. Withstands peak temperatures near 200 °C. Pumps well | Cement, mining and metals: wet, hot and heavily loaded bearings and pivots |
| Anhydrous calcium soap, high load | Water resistance, corrosion protection, mechanical stability, wear protection, pumpability. A replacement for general and EP lithium greases | General heavy-load bearings, conveyors |
| High-viscosity EP grease with solid lubricants | A film that persists on open gears and sliding contacts | Kiln tyres, riding rings, girth gears, ball mill gears |
| High-performance high-temperature and electric-motor greases | Stable at high speed and temperature, quiet in ball bearings | Motors, fans, hot ends of kilns |
| Environmentally accepted ester-based grease | Biodegradable or low-toxicity base oil | Open or environmentally sensitive areas, mobile equipment near water |
Match to the job
- Slow and heavily loaded: high-viscosity base oil with solids.
- Hot and wet: calcium sulfonate complex.
- Fast and light (fans, motors): lower viscosity high-temperature or motor greases.
- Mixed fleet: pick as few grease types as the equipment allows to cut mix-ups.
Compatibility
Do not mix thickener types without checking. When changing grease class, purge the old grease or check the compatibility chart before the change.
Takeaway. Choose the grease for the contact, not for the shelf. Heavy and slow means a high base-oil viscosity and solids. Hot and wet means calcium sulfonate.
Put it to work in the tool