Ultrasonic cleaners are popular because they clean parts and equipment thoroughly and efficiently, work on a wide range of materials, and remove a tremendous variety of contaminants. With all that said, the process is not universal.
Ultrasonic cleaning times vary according to a number of variables: the type of contaminant, the cleaning detergent used, the solution temperature, and the frequency and intensity of the ultrasonic cleaners the parts are placed in.
Since ultrasonic cleaners can remove contamination from everything from a cast iron engine block to a semiconductor wafer, it only makes sense that cleaning cycles vary in duration; it really depends on what contaminants we’re trying to remove, and how clean we want the part to be when we’re done.
Without any specific knowledge, it’s hard to predict how long ultrasonic cleaning cycles may take. To help out, we’ve listed in the table below some of the parts we’ve cleaned in ultrasonic cleaners over the years, along with their cleaning times, solution temperatures, and frequencies. These can be used as a starting point when we’re looking for a new machine, or getting ready to clean a different type of part in our existing machines:
Determining how long a cleaning cycle should take in our ultrasonic cleaners is not exact when we’re cleaning a part for the first time, but is very predictable when we clean the same part over and over again if the type of contamination remains constant. Once we find the proper combination of time, temperature, and cleaning detergent, we can be very confident that the cleaning time will be the same from batch to batch. Our goal then is to begin shortening the cycle length to save time and money, and seeing just how much energy we can save yet still achieve similar results.The type of contaminant plays a significant role in the length of time needed for cleaning in ultrasonic cleaners.
Materials that are generally loose like dirt, metal shavings, and soot, can be quickly removed from a part, since there’s little interaction between the part and contaminant to hold it in place. Oil and grease contamination require much longer cleaning cycles, because oil molecules tend to bond with surfaces like plastics and metals, and the implosion forces generated in ultrasonic cleaners must break those bonds. Grease has a wax binder, and bonds well to itself in addition to bonding strongly with other materials. Carbon deposits, mill scale, and oxidation are probably the hardest contaminants to remove.
Heat and the proper detergent are keys to quickly removing these materials.Looking at the chart, we quickly see that the times, temperatures, and frequencies used to clean parts vary dramatically because the base materials of the parts and types of contaminants are so diverse. The materials range from cast iron to steel, brass, plastic, and polished stainless steel, while the contaminants vary from grease and oil to baked-on carbon, mildew, mold, solder flux, rosin, and bacteria. We ask a lot of our ultrasonic cleaners, and they perform admirably.