After the ore-ressing plant in a gold mine from Zhaoyuan introduced Metso mining machinery company HP400 multi-ank cone crusher to replace domestic PYD1650 short-ead spring cone crusher,the crushing system incurs the problems that the grain size of the crushing product and the crushing capacity fail to meet expectations and production materials consumption is huge.Therefore,the problems are analyzed and secondary renovation is implemented.The maximum run-of-mill ores feed grain size is controlled below 500 mm,the crushing and screening process flow is adjusted into 3 stages and 1 closed circuit,and the double-layered round vibration screen is changed.After that,the capacity of crushing system is improved by 10.70 % to 2 380 t/d; the load rate of double-ayered round vibration screen is down to 74.78 %;the grain size -5 mm in the crushing products accounts for as high as 59.79 %.The steel ball consumption in the ball mill system is down by 0.16 kg/tore,the power consumption is down by 1.24 kW·h/tore.The outcome of more crushing less grinding,and energy conservation is achieved.