Immersion

Immersion is the most versatile of the cleaning methods, particularly for cleaning irregular shapes, box sections, tube and cylindrical configurations that cannot be penetrated using spray systems. The operation may vary from hand dipping a single part or agitating a basket containing several parts in an earthenware crock at room temperature to a highly automated installation operating at elevated temperature and using controlled agitation.

The types of cleaner used in immersion systems are often chemically similar to spray cleaners but due to lack of impingement are generally run at higher concentrations. Efficient cleaning by immersion depends on placing work pieces in baskets or on racks to avoid entrapment of air or nesting of parts.

As the cleaner acts on the parts, convection currents (due to heating or mechanical agitation) help to lift and remove soils from the metal surface. The efficiency of removal by the soak cleaner is greatly enhanced by agitation.

There are several approaches to immersion cleaning:
- Barrel cleaning is often used for large quantities of small parts which are agitated inside a barrel that rotates in the cleaner solution. In some instances, a medium such as stones is added to the charge, frequently comprising up to two-thirds of the total load.
- Moving conveyor cleaning in which solution flow is created as parts are dragged through the cleaner.
- Mechanical contact in which the cleaner is applied with external forces such as brushes or squeegees.
- Mechanical agitation in which the cleaner is circulated using pumps, mechanical mixers, or ultrasonic waves.
This can be realised by flooding the empty bath, which contains the component already. The to be cleaned parts are flooded with high velocity. An additional cleaning effect is realised by the vacuum effect of the liquid flowing past blind holes flushing out the dirt. When using very high velocity it can also come to tiny gas bubbles as in ultrasonic cleaning. Another advantage is that the created turbulence will not allow the building up of oily layers on the bath surface, so parts cannot be resoiled while they are moved out.
High pressure agitation (German: Druckumfluten) is suitable for deep and blind holes as well as for pipes, tubes or bundles of pipes and tubes with a small diameter. A wide range of different types can be used as agents.

	Prevention, SDS, column-model, etc.
	Producers, suppliers
	Optimisation potential
	References

back	List of all database-processes with this method	forward