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.
Pulverized coal pipes wear by erosion from fine particles, not by sliding ore
Coal ground in the mill is carried by air to the burners at a speed that keeps it suspended, and every change of direction throws the particles against the outer wall. The damage is a concentrated groove rather than a uniform loss, which is why a bend can fail while the straight pipe beside it looks almost new.
Bends take the most wear, and where they wear depends on the flow upstream
The outer radius of each bend is the obvious target, but a bend just after another bend, a damper or a splitter wears off-centre because the flow arrives uneven. The mechanism is the same as in other pneumatic lines, described in pneumatic conveying bend erosion and in dilute and dense phase bend wear.
Splitters, riffles and orifices wear on their leading faces
Wherever the coal flow is divided between burner pipes, the dividing edges and the faces facing the stream erode, and wear there also upsets the balance between burners. These are small, shaped parts that standard tiles do not fit; they are usually lined or replaced with shaped ceramic made to drawing, as with IC CUSTOM.
The mill classifier and outlet see the same fine-particle erosion at lower speed but over larger areas
Classifier cones, vanes and the mill outlet ducts lose material steadily where the flow turns. Hard alumina tiles such as IC TILE suit these larger surfaces, provided the layout keeps joints out of the main flow path and the transitions flush.
Coal service adds safety and temperature constraints to the lining choice
Mill outlet temperatures limit some adhesives, coal dust makes hot work subject to strict permits, and any loose fragment entering the burner line is a risk. That favours retention methods that suit the temperature and the site’s hot-work rules — compared in bonded versus weldable fixing — and lined pipe spools fabricated before the outage, such as IC PIPE, so that the work on site is limited to swapping spools.
The data a supplier needs for a coal system
Provide the mill type, the pipe diameters and routing with bends, splitters and dampers marked, the air velocity and coal flow, the temperature, the current materials and their life per component, photographs of worn bends, and the site’s rules for hot work. The ceramic-lined pipe specification checklist covers the spool details.