Switching to Aqueous Cleaning
Aqueous and organic solvent cleaning are commonly taking the place of solvent vapor degreasing in metalworking shops, mainly because they are safer for the environment and for workers in the shop where they are used. If your shop is in need of making the switch to aqueous cleaning, there are several articles on Production Machining’s website that can help.
According to “Choosing an Aqueous Parts Washing System,” the first step in choosing any cleaning system should start with understanding the soil to be removed as well as the parts from which that soil needs to be removed. You should know how clean the parts need to be and what the measure of cleanliness is.
Next, a test cleaning machine should be brought in on the shop floor by a supplier found here at productionmachining.com, if you don’t already have a supplier. Test data will gather specific information about temperature, operating concentration, the mechanical energy and more importantly, the length of time required for effective cleaning.
The type of cleaning equipment needed should also be determined. According to “Fast Track to Rugged Aqueous Cleaning,” the three cleaning stages—wash, rinse and dry—aren’t always necessary for every operation. You should determine whether or not you need the rinse and dry cycles, and set a budget.
The cleaning chemistry and cleaning equipment have to be considered in parallel. The appropriate chemical blend for your process also depends on the soil being removed and on the surface being cleaned.
To read about a shop’s process of moving from an old chlorinated solvent cleaning machine to aqueous cleaning, read “Moving Away from Solvent Vapor Degreasing.”
A turbine manufacturing plant phases out an obsolete vapor degreasing system, making the change to aqueous-based cleaning.
Parts cleaning, like most metalworking processes, is experiencing ever tightening specifications. Shops must continuously evaluate whether to clean parts in-house or use a supplier. This article looks at current aqueous cleaning processes and suggests criteria for the make or buy decision.
For precision parts that need to have some type of finish applied to them, inadequate cleaning and pretreatment is the biggest cause of defective painting or plating.