When we see an ideally worn set of lines with a utilization rate of 70 percent or a little higher, and which features a straight worn surface from the feed end to the discharge end, while producing at a uniform output rate -- we'll also see a crusher that got fed a uniformly sized range of in-feed and was run at an optimum discharge setting for the crusher model. Those are the most key factors in getting bowls and mantles to wear out right.

We've found the geometry involved goes like this: Getting the discharge match point in a cone crusher correct to its application is accomplished by aligning the discharge end of finer crushers, perpendicular to the sizing zones, near the most closed side. Coarser crushers that are run with larger discharge settings are aligned more to the vertical diameter of the B-liner. Cone crushers are designed to operate at a given setting and departures from that ideal number increasingly diminish the ability to obtain an ideal wear pattern.

The new generation of high-speed / high throw cone crushers adds another dimension to the ability to obtain an ideal discharge match point. Because of the increase in crusher head speed and eccentricity action, the ideal match point for a specific material is more difficult to identify. The ideal match point with these crushers may be at a point of alignment between the B-liner and mantle that is somewhere off the true closed side position. That means overlaying the "new gen" crushers at the closed side position for feed opening reasons will often result in discharge mismatch appearance.

When the worn mantle looks to have a hump at the big end, the B-liners discharge point is too short and is often the result of the crusher being run at a closer setting than its optimum (i.e., a 4 1/4' Symons standard being run at a .375" closed side setting, or C.S.S.) If the B-liner shows a hook at its discharge end, it's being run at too open a C.S.S. (i.e., a 4 1/4' Symons standard, being run at 1.250" C.S.S.) Either condition forms a "fence like" appearance, limiting best through-put rate. Running a cone crusher out of its ideal setting range will compromise liner performance.