Bath Temperatures can Drastically Affect Cleaning Performance.

The temperature at which an ultrasonic cleaning system operates plays a role in the distribution of ultrasonic cleaning action, the power of the ultrasonic cleaning action, and the effectiveness of the detergents being used.

Traditional ultrasonic theory suggests that the best temperature for use in an ultrasonic cleaning system is typically 65% of the boiling point of the solution. Although this formula has been used as a general guideline to determine optimum temperatures for decades, it rarely plays a role in determining optimum temperatures for any given application. Temperatures are usually related more to the effectiveness of the cleaning agent in use rather than the effectiveness of the ultrasonic cleaning system. Each cleaning fluid may have an optimum temperature at which it performs best. This is the temperature that is normally used for a given ultrasonic cleaning application.

Increases in fluid temperatures will improve the distribution of ultrasonic cleaning action in the tank but can also REDUCE the scrubbing force. As temperatures increase above 80°F, you will find that the scrubbing action is more evenly distributed and less powerful than at higher frequencies. Simple tinfoil tests can be used to confirm this information. as temperature increases, holes in pieces of aluminum foil take longer to produce. However, the foil will appear to be more evenly attacked by the ultrasonic energy present. Large holes in the foil are replaced by smaller more evenly distributed holes, and dents are visible in between the holes produced by the standing waves in the ultrasonic cleaning tank.

Although the physical scrubbing force of the ultrasonic cavitation is reduced at elevated temperatures, the improvement in the effectiveness of the cleaning agent can overcome the reduction in ultrasonic power. Some cleaning agents work best at elevated temperatures. By operating the ultrasonic cleaner at these temperatures, the cleaning agent has an improved ability to loosen the bond strength between the parts being cleaned and the contaminant in question to a point where existing ultrasonic energy can remove it from the surface, even with reduced scrubbing power.

Acidic cleaning agents should not be heated excessively, as many of these fluids can attack the stainless steel that the tank is manufactured of. When using these fluids, it is best to use as low a temperature as possible to avoid such potential damage.

Temperature Effects:

  • Best Ultrasonic Performance is roughly 65% of the Boiling Point of the Fluid in Use
  • Temperature Above 65% of the Boiling Point will Decrease Scrubbing Force of the System, but will Improve Distribution of that Force.
  • Most Ultrasonic Cleaners Utilize Temperatures between 130 and 180 degrees F.
  • When Using Acidic Materials, Use the Lowest Temperature Possible to Reduce Potential Damage to the Stainless-Steel Tank.