The grinding table is the foundation of every vertical roller mill — the rotating surface upon which grinding rollers press to comminute feed material. LIMING manufactures and refurbishes VRM grinding tables in wear-resistant materials with segmented designs for economical maintenance and extended service life.
The grinding table of a vertical roller mill is a large, horizontally rotating disc that works in concert with the grinding rollers to crush and grind material fed from above. Feed material drops onto the center of the rotating table and is distributed outward by centrifugal force. As the material passes under the grinding rollers, it is crushed between the roller and table surfaces. The continuous grinding action progressively reduces particle size until the material is fine enough to be entrained in the gas stream flowing upward through the mill.
The grinding table is subjected to extreme wear from direct contact with abrasive materials such as limestone, clinker, slag, and coal. This makes the selection of wearing surface materials and the ability to efficiently replace worn sections critical to mill availability and total grinding cost. LIMING offers grinding tables in two primary construction types — integral cast (for smaller mills) and segmented (for larger mills where in-situ replacement of individual segments is essential).
Whether you need a complete replacement grinding table or reconditioning of an existing table with new wear liners, LIMING's foundry and machining capabilities can accommodate tables for all major VRM brands and sizes.
| Material Type | Wear Resistance | Hardness | Toughness | Best For |
|---|---|---|---|---|
| Ni-Hard Cast Iron | High | HRC 55-62 | Moderate | Raw material grinding, coal grinding |
| High Chrome White Iron | Very High | HRC 58-64 | Low-Medium | Highly abrasive materials, slag grinding |
| High Chrome Overlay (Hardfacing) | Extreme | HRC 60-65 | Base: tough steel | Cement clinker grinding, longest life |
| Ceramic Composite | Maximum | HRA 85+ | Low | Extreme wear applications |
Wear protection is the most critical aspect of grinding table design. LIMING employs several strategies:
In-house foundry, precision machining, and specialized wear protection expertise.
Large-capacity foundry producing Ni-hard and high-chrome castings up to 15 tons per piece. Full metallurgical control from melt to finished product.
CNC turning and grinding ensure flatness within 0.05 mm/m and precise mating surfaces between segments for even roller-table contact.
Automated hardfacing equipment deposits uniform chrome carbide overlay layers. Re-hardfacing service extends part life by 2-3x.
We manufacture and stock individual table segments, so you only replace what's worn. Fast delivery of single segments available.
| Parameter | Specification |
|---|---|
| Table Diameter Range | 1,500 mm – 6,000+ mm (all VRM sizes) |
| Table Construction | Integral casting (small) or segmented (4-12 segments for large mills) |
| Base Material Options | Ni-hard, high-chrome white iron, alloy steel |
| Wear Surface | Through-hardened or high chrome carbide overlay (CCO) |
| Wear Layer Hardness | HRC 55-65 (HRC 60-65 for CCO) |
| Wear Layer Thickness | 5-15 mm (overlay), full depth (through-hardened) |
| Surface Flatness | ≤ 0.05 mm/m after machining |
| Segment Unit Weight | 500 kg – 5,000 kg per segment |
| Re-hardfacing | Available — extends life 2-3x |
| Lead Time (New) | 60-90 days (casting + machining) |
| Lead Time (Re-hardfacing) | 15-30 days (depending on condition and size) |