Abstract: Ultrasonic wire cleaning apparatus in which elongated strands of wire are advanced continuously through a bath of acid contained in a tank. Ultrasonic transducers are located in the tank and produce ultrasonic energy which coacts with the acid to effect cleaning of the wire. The transducers are submerged in and are cooled by a separate bath of water located in the tank beneath the acid and are protected against erosion by a rigid plastic plate which separates the acid from the water. Water-filled chambers at the sides of the tank keep the head of the water bath greater than the head of the acid bath in order to prevent the acid from leaking downwardly into the water and contacting the transducers.