The old customer in Guangxi Hezhou repurchased the ultra-fine grinding machine, the customer is doing ore powder processing. Since the cooperation, Kolev after-sales service team has been maintaining good communication with customers. Train the customer operation skills, regularly visit the customer machine working situation, timely help the customer to solve the daily maintenance and other small problems. According to customer feedback, Kolev ultra-fine grinding machine high efficiency, low energy consumption, stable working state, simple operation, grinding out the finished powder state and quality are good, bring considerable economic profits to customers, so it will buy back.