What Is Cavitation in Ultrasonic Cleaning?
Cavitation is a physical phenomenon caused by the formation and rapid collapse of very small bubbles within the ultrasonic cleaning liquid. In ultrasonic cleaning systems, this process helps remove contaminants and production residues from the surfaces of parts.
When vibrations generated by the ultrasonic generator and transducer system are transferred into the liquid, pressure variations occur. The collapse of the microscopic bubbles created by these pressure changes produces a mechanical cleaning effect on the surfaces being cleaned.
How Does Cavitation Provide Cleaning?
In conventional mechanical cleaning methods, brushes or similar equipment need to come into direct contact with the surface. In ultrasonic cleaning, however, the cleaning effect is generated through cavitation within the liquid.
This characteristic makes ultrasonic cleaning particularly useful for cleaning recesses, holes, channels and areas that are difficult to reach manually.
However, effective cleaning requires more than simply generating cavitation. Ultrasonic energy must also be distributed appropriately throughout the working volume of the tank.
What Is an Ultrasonic Transducer and What Does It Do?
An ultrasonic transducer is a system component that converts electrical energy from the ultrasonic generator into high-frequency mechanical vibrations. These vibrations are then transferred into the cleaning liquid inside the tank.
Transducers are therefore among the key components responsible for creating cavitation in an ultrasonic cleaning system.
Why Is Transducer Placement Important?
High ultrasonic power alone does not guarantee uniform cleaning performance. How the ultrasonic energy is transferred into the working area of the tank is also important.
The position of the transducers should be determined by considering the width, length and depth of the tank, the geometry of the parts being cleaned and their placement within the tank.
Bottom-Mounted Transducers
Placing transducers on the bottom surface of the tank is one of the commonly used configurations in ultrasonic cleaning machines. In this arrangement, ultrasonic energy is transferred into the liquid from the bottom of the tank.
Bottom-mounted transducers can be suitable for many standard applications with appropriate tank geometry. However, as tank depth and part complexity increase, the overall system design should be evaluated accordingly.
Side-Mounted Transducers
When transducers are positioned on the side walls of the tank, ultrasonic energy can be transferred into the liquid from the sides.
Side-wall placement may be considered especially for deep tanks, long components or applications where the surfaces to be cleaned are positioned closer to the sides of the tank.
What Is Opposing Transducer Placement?
In some systems, transducers may be positioned on two opposing sides of the tank. This allows ultrasonic energy to be introduced into the working area from more than one direction.
This configuration may be suitable for processes involving large, densely loaded or geometrically complex parts. However, it is not necessary for every application and should be selected according to process requirements.
Does Tank Geometry Affect Cavitation Distribution?
Yes. Two tanks with the same volume may have different widths, lengths and depths. These differences can affect how ultrasonic energy is distributed throughout the working volume.
For this reason, an ultrasonic cleaning system should be evaluated not only according to tank capacity but also according to tank geometry.
Is the Position of Parts Inside the Tank Important?
Placing parts too close together or allowing them to block one another can reduce the effectiveness of ultrasonic cleaning on certain surfaces.
Basket design, spacing between parts and the position of the components in relation to the transducers should also be considered as part of the ultrasonic cleaning process.
Do More Transducers Always Provide Better Cleaning?
No. A higher number of transducers does not automatically mean better cleaning performance.
The important point is to generate the required ultrasonic power and distribute that energy appropriately throughout the working area of the tank.
What Factors Affect Cavitation?
- Ultrasonic frequency
- Ultrasonic power
- Number and placement of transducers
- Tank geometry
- Properties of the cleaning liquid
- Cleaning temperature
- Position of the parts inside the tank
Cavitation and Transducer Design in Plussonic Systems
In Plussonic ultrasonic cleaning systems, tank structure, characteristics of the parts to be cleaned, process capacity and required cleaning performance are evaluated together to determine the appropriate system configuration.
Determining ultrasonic frequency, power and transducer placement in harmony with each other is important for achieving an efficient ultrasonic cleaning process.
Frequently Asked Questions
What is cavitation?
Cavitation is the physical effect created when microscopic bubbles form and collapse in a liquid as a result of ultrasonic vibrations.
What does an ultrasonic transducer do?
A transducer converts electrical energy from the ultrasonic generator into mechanical vibrations and transfers them into the cleaning liquid.
Where are ultrasonic transducers installed?
Depending on system design, transducers can be installed on the bottom, side walls or opposing surfaces of the cleaning tank.
Does increasing the number of transducers improve cleaning?
Not necessarily. Total ultrasonic power, transducer placement, tank geometry and energy distribution should all be evaluated together.
Does ultrasonic frequency affect cavitation?
Yes. Ultrasonic frequency is one of the main parameters that affects the characteristics of cavitation generated within the cleaning liquid.