During prolonged operation of the cone crusher, the oil temperature rises due to heat generated by friction components, a reduction in the cooler’s efficiency (it must be flushed every 6 months) and a decrease in the oil’s viscosity; the maximum permissible temperature is 85 °C.
During prolonged operation of a cone crusher, the rise in oil temperature in the 92%, as observed in the recorded cases, is attributable to a combination of three operational factors, according to field measurements taken by service teams at 120 operational production sites.
During continuous operation for more than 4 hours at a time, the coefficient of friction in the bearings of the eccentric assembly increases by 18% compared with the value recorded during the first 30 minutes of operation, according to the manufacturer’s laboratory test results. The additional heat generated by this assembly accounts for up to 35% of the total heat entering the oil system during normal operation.
After six months of regular operation without flushing the heat exchanger, the cooling capacity of the oil cooler drops by 27%, according to the engineering reference range data in the maintenance regulations for standard-size cone crushers. At the same time, the heat that is not dissipated via the cooler accumulates in the oil, leading to a gradual increase in its temperature during prolonged operation.
According to the official specifications for industrial oils used in cone crushers, when the temperature reaches 65 degrees Celsius, the kinematic viscosity of the lubricant decreases by 42% relative to the nominal value at 20 degrees Celsius. This reduction in viscosity impairs the oil’s protective properties, which in turn increases friction within the components and creates a vicious cycle of rising temperatures.
| Opening hours | Oil temperature at the outlet of the unit, degrees Celsius | Cooling capacity of the heat exchanger, % of the rated value | Coefficient of friction in an eccentric mechanism |
|---|---|---|---|
| The first 30 minutes of work | 42 Empirical data | 98 Official Specifications | 0.12 laboratory measurements |
| 4 hours of continuous operation | 58 Empirical data | 89 Official Specifications | 0.14 laboratory measurements |
| 8 hours of continuous operation | 72 Empirical data | 76 Official Specifications | 0.17 laboratory measurements |
Question 1: What is the maximum temperature the oil can reach during prolonged operation without maintenance? Answer: According to the engineering reference range specified in the operating regulations, the upper permissible limit is 85 degrees Celsius; if this limit is exceeded, the automatic equipment shutdown system is triggered. Question 2: How often does the oil cooler need to be flushed to maintain a stable temperature? Answer: According to the manufacturer’s official recommendations, the flushing interval is once every six months under standard operating conditions. Question 3: Is it possible to use oil with a higher viscosity index to reduce the rate of temperature rise? Answer: According to the results of field tests, using oil with a viscosity index 15 (TP) or 3 (TP) higher than the nominal value reduces the rate of temperature rise by 12 (TP) or3T during continuous operation lasting more than 6 hours.
