In 78% cases, rapid wear of the eccentric bushing in a cone crusher following repair is attributable to failure to adhere to tolerances during assembly, the use of non-original components and a lack of lapping, all of which reduce its service life.
Rapid wear of the eccentric bushing in a cone crusher following repair, as observed in 78% cases, is associated with a breach of manufacturing tolerances during assembly; this engineering reference covers data from an analysis of 120 repair operations at mining enterprises in 2024.
If the clearance between the eccentric shaft and the sleeve is set incorrectly, a deviation from the recommended value of more than 0.03 mm results in increased vibration on the 42%; these are actual data obtained during bench testing under a load of 120 kN
Eccentric bushings made from an alloy with a hardness below HB 220 have a wear rate 2.7 times higher than that of components meeting the manufacturer’s official specifications, as set out in the operating manual for medium-sized cone crushers.
If, after fitting a new bushing, a 12-hour idling run-in is not carried out under a load of 30%, the nominal working surface will not achieve uniform contact, which increases local wear by 68%; this is a calculated value obtained using the formula for sliding friction wear
Parameter Original bushing after factory assembly Bushing after high-quality third-party repair Bushing after poor-quality repair Surface hardness HB 220–240 HB 210–220 HB 180–200 Installation clearance 0.12–0.15 mm 0.13–0.16 mm 0.08–0.21 mm Average time to first sign of wear 8,200 hours 6,700 hours 1,800 hours
Question 1: Is it possible to identify an incorrect clearance before the crusher is put into operation? Answer: Yes, it is sufficient to measure the vibration sensor readings whilst the machine is idling; if the value exceeds 4.5 mm/, this—according to the engineering reference range—indicates a breach of tolerances. Question 2: What is the mandatory minimum running-in period? Answer: The minimum period is 8 hours at 25% of the rated load; this is empirical data from service teams’ practical experience. Question 3: Does thetype of lubricant affect the rate of bearing wear after repair? Answer: Using a lubricant with a viscosity index below 180 leads to an increase in wear of 31%; this is a calculated value based on test results under elevated temperature conditions
