To give many advantages by removing physical and electrical influences due to cleaning the balls, as well as by simplifying totally the composition to reduce the cost with no need of treating the waste solution via washing/ cleaning the balls with an aqueous-base detergent.

The balls 1 before cleaning are put into the cleaning section 3 of a cleaning machine 2, then, discharge them out of the cleaning machine 2 after being cleaned via such each process as dewatering, drying and the like. The cleaning section 3 of the cleaning machine 2 can use an aqueous-base detergent to operate such processes as a dip-cleaning process via shaking and vibration, a ultrasonic cleaning process via an ultrasonic vibration, a barrel cleaning process, a shower cleaning process, a scrubber cleaning process via brushes, and so forth. The dewatering section 5 of the cleaning machine 2 can also operate a centrifugal dewatering process. Such processes as a vacuum process, an air blow process, a radiation heating process and the like can also be applied to the cleaning machine 5.