Ultrasonic cleaning  is a process that uses  ultrasound  (usually from 20–40  kHz ) to agitate a fluid. The ultrasound can be used with just water, but use of a solvent appropriate for the object to be cleaned and the type of soiling present enhances the effect. Cleaning normally lasts between three and six minutes, but can also exceed 20 minutes, depending on which object has to be cleaned. [1] Ultrasonic cleaners are used to clean many different types of objects, including  jewelry ,  lenses  and other optical parts,  watches ,  dental  and  surgical instruments ,  tools ,  coins ,  fountain pens ,  golf clubs ,  fishing reels ,  window blinds ,  firearms , car  fuel injectors , musical instruments,  gramophone records ,  industrial machine parts and electronic equipment. They are used in many jewelry workshops,  watchmakers ‘ establishments, and electronic repair workshops