4 Tank ultrasonic cleaning equipment

Four-tank lines add a stage that three tanks cannot provide: either a spray station or a second rinse, both aimed at what remains after the main wash.
The spray stage matters for parts with blind holes, deep bores and internal passages, where immersion alone leaves liquid sitting in features that never fully drain. Directed spray flushes those out before drying. The double-rinse configuration takes a different approach: two rinses in series dilute residual chemistry much further than one, which is what hydraulic components and medical parts need when there is a specified residue limit rather than a visual standard.
Both variants exist because the requirement is measurable. If your specification states a residual limit, a particle count or a cleanliness class, that number should drive the tank count — not the other way round.