Evidence-first editorial standard
This guide separates observed facts, engineering assumptions and data that still require confirmation. It does not promise a universal service life or replace the exact product data and project specification.
A separator wears by erosion, and erosion follows the gas
In high-efficiency separators of cement mills and in the classifiers of vertical roller mills, ground material is carried by air through guide vanes into a rotating cage, where fines pass and coarse particles fall back. Wherever the dust-laden gas changes direction or speeds up, fine hard particles erode the steel. The wear is therefore predictable from the gas path, as part of the plant-wide picture in cement plant wear protection by circuit.
Guide vanes, the reject cone and the inlet are the usual hotspots
Static guide vanes take the full stream at an angle and wear at their leading edges. The reject or grit cone sees sliding abrasion by the coarse fraction falling back to the mill. Inlet ducts and volutes erode on the outer wall where the stream turns. The rotor blades wear too, but they are balanced rotating parts whose repair belongs to the separator manufacturer; lining decisions are about the static parts.
Ducts, cyclones and product lines: the second ring of wear
After the separator, the fine product is carried to cyclones or a filter; cyclone inlets, the cone of each cyclone and the ducts and bends on the way erode, particularly on the outer radius. Process fans downstream wear at the impeller and casing, as described in fan casing wear liners. Shaped segments in IC CUSTOM suit cyclone inlets and cones; tiles in IC TILE cover duct walls and the reject cone.
Temperature, weight and balance set the limits
Separators and mill classifiers often run with hot gas from the kiln or a hot-gas generator, so the steel temperature determines whether an adhesive can be used or a weld-on fixing is needed; see choosing an adhesive for ceramic tiles. Ceramic on static parts adds weight to the casing, which the structure must carry, and nothing should be added to rotating parts without the manufacturer’s approval. Clearances between rotor and static parts must be kept.
Measure wear in the same places at every stop
Thickness readings on vane edges, the reject cone, inlet and cyclone walls, recorded at the same points each outage, show where the wear rate is highest and whether a lining is working. The method in comparing wear measurements between shutdowns applies directly. Changes in fineness, throughput or the clinker or slag ground change the wear rate and must be noted with the readings.
What to send for a separator lining quote
Send the separator or classifier type and drawings of the static parts, the gas temperature at the steel, the product (raw meal, cement, slag, coal), throughput and fineness, the measured wear and the current protection, and the outage window. Induscoat then proposes the static parts to line with IC BOND or weld-on fixing. The cyclone approach is on our page on ceramic-lined cyclones and hydrocyclones, and the ducts on pneumatic conveying, fans and ducts.