Seals
Cement plant seal map: what each stage asks of its seals
Quick answer
A one-page map from quarry to dispatch with the main seal duty at every stage: dust, oil, heat, big shafts, hydraulics and mobile equipment.
How to read the map
Each box is a stage of the process, and the numbered dots show which seal duties matter most there. The first dot is usually the most demanding. The map is a guide to where to look first, not a specification: sizes, speeds and conditions differ from plant to plant.
Stage by stage: seal duty and what usually goes wrong
| Stage | Main seal duty | What usually goes wrong | What helps |
|---|---|---|---|
| Quarry operations | Hydraulics, wheel hubs, track pins, dust | Rod seals scored by dirt, hub seals worn by fine dust | Good wipers, wear-resistant materials, cassette or metal face seals on hubs |
| Crushers, screens, conveyors | Keep abrasive dust out of bearings and gearboxes | Lips wear through, grease purges out and dirt enters | Labyrinth or multi-lip protection and V-rings over the main seal, purge with fresh grease |
| Raw mill and silos | Oil retention in gear drives, dust exclusion on roller bearings | Oil weeps past worn lips, dust enters the roller housing | Right lip material for the oil, clean breathers, air purge where fitted |
| Preheater and kiln line | Heat, fine hot dust and large rotating parts | Rubber hardens and cracks, shafts wear under the lip | High-temperature materials, wear sleeves, split seals for big shafts |
| Clinker cooler | Heat, hydraulics and fan bearings | Grate drive and ram seals age quickly in the heat | Heat-rated seal materials, shielding from radiant heat |
| Roller press and cement mill | Heavy shock, oil retention and dust exclusion | Seal lips overloaded by shaft movement and vibration | Seal types that tolerate shaft run-out, split designs for mill trunnions |
| Separator, silos, packing | Fine dust everywhere | Dust packs behind seals and wears the shaft | Dust seals plus V-rings, regular cleaning, correct relubrication |
| Dispatch and loaders | Mobile equipment hubs and hydraulics | Wash-down and weather damage | Tough hub seals, covers and sealed connectors |
Where seals usually repay the effort first
- Kiln line and cooler: heat shortens seal life, so material choice matters most
- Mills and roller press: big shafts, so split or weldable seals avoid long strip-downs
- Conveyor and crusher drives: dust exclusion decides bearing life
- Mobile fleet: hubs and hydraulic cylinders take the most abuse per year
Link to bearings
On the Equipment Anatomy plant map every machine shows its bearing positions. Use the two together: the bearing page tells you what is inside the housing, and this map tells you what is keeping the dust out.
Takeaway. Every stage has a main seal duty. Match the seal to that duty first, then to size and speed.
Put it to work in the tool