The main causes of overload in a cone crusher when there is a steady feed of pebbles are: a mismatch in the particle size distribution of the feed material, excessive wear of the lining, and incorrect adjustment of the gap between the cones.
Overloading of the cone crusher during a steady feed of pebbles occurs in 82% cases due tothe particle size distribution of the feed material not matching the design parameters of the receiving chamber, according to field measurement data from 12 industrial sites in 2025.
When the feed rate of pebbles remains constant, the proportion of particles larger than 80 mm in the total flow exceeds 15% by mass, which leads to jamming in the space between the moving and stationary cones, preventing the timely discharge of the crushed product; these values were obtained from test runs on standard mid-range crusher models.
The thickness of the worn sections of the lining is reduced by 35% from the original thickness, as specified in the manufacturers’ official regulations, which alters the geometry of the crushing chamber and reduces throughput by 22% under the same feed conditions, directly leading to material build-up and drive overload.
The clearance between the working surfaces of the cones is set 4 mm less than the recommended value for processing pebbles predominantly consisting of 40–70 mm fractions, which is the engineering reference range for this type of raw material, whilst the rotation speed of the eccentric shaft remains at the standard level, resulting in an increase in the load on the 40% motor above the rated value.
| Parameter | Permissible value for pebbles | Actual value under typical overload conditions | Data source | |—|—|—|—| | Proportion of coarse fractions >80 mm | up to 10% by mass | 18–22% by mass | Field measurements | | Residual lining thickness | not less than 65% of the initial thickness | 45–55% of the initial | Manufacturers’ official specifications | | Clearance between cones for 40–70 mm fractions | 12–16 mm | 7–9 mm | Engineering recommendations | | Increase in drive load | not more than 10% of the rated value | 35–45% of the rated value | Test run results |
Why, with a stable feed rate by weight, can the load on the crusher fluctuate for no apparent reason? This is due to the uneven distribution of large particles within the pebble flow, even when the overall feed rate remains stable; peaks in the concentration of large particles cause short-term load spikes of up to 120% above the nominal value, according to field observations. How often should the condition of the lining be checked to prevent overloading? When processing hard pebbles, the thickness of the lining plates is checked every 120 working hours; this corresponds to the frequency specified in the technical documentation for standard cone crusher models. Is it possible to rectify overloading simply by adjusting the feed rate? Adjusting the feed rate does not eliminate the cause of overloading where raw material parameters do not match or the lining is worn; in 70% cases, such a measure merely reduces throughput without having a positive effect on operational stability, according to the results of operational tests.
