What is Ultrasonic Cleaning?

Ultrasonic cleaning is the rapid and complete removal of contaminants from objects, achieved by immersion in a tank of liquid which is then flooded with high frequency sound waves.

These non-audible sound waves create a scrubbing action within the fluid, brought about by high frequency electrical energy that is converted by a transducer into high frequency sound waves – ultrasonic energy.

How does it work?

Ultrasonic energy enters the liquid within the tank and causes the rapid formation and collapse of minute bubbles; a phenomenon known as cavitation. The bubbles travel at high speed within the tank, causing them to implode against the surface of the immersed item with an enormous release of energy. This gently lifts contaminants from both the surface and innermost recesses of intricately shaped parts.

As the bubbles implode and cavitation occurs, the cleaning solution rushes into the gap left behind by the bubbles. When the cleaning solution makes contact with the item in question, any contaminants, dirt and tarnishing which are present simply falls away.

Choosing the right ultrasonic cleaning system

Size

Ultrasonic cleaners come in a wide range of dimensions and capacities. You need to consider how large the items are that will be cleaned and how many items on average will be cleaned during one cycle.

Ultrawave manufacture ultrasonic cleaners ranging from small baths of less than one litre to larger multistage systems.

Tank Specification

The specification and thickness of the tanks in ultrasonic cleaners can vary. For light and infrequent use, Benchtop ultrasonic baths have a pressed tank of 0.6-0.8mm thick stainless steel.

For applications where the machine is to be used more regularly, an Industrial grade tank of 2mm thick stainless steel is always recommended.

In many cases, 316 stainless steel tank is specified for cleaning medical device components with radius corners. This prevents trapped dirt and facilitates easy cleaning.

Control

Entry level ultrasonic baths have an analogue dial for simple time and/or temperature control. For more advanced applications, ultrasonic systems incorporate a menu-driven digital control allowing more accurate and precise

programming of the system functions.

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Transducer Efficiency

The efficiency of the transducer used in your ultrasonic cleaning tank will affect both the cleaning time and efficiency achieved during the cycle. A poor quality transducer will use more power and take longer to clean items than an advanced transducer.

Ultrawave have invested a significant amount of time and money into the design and development of our transducers, providing you with superior cavitation performance.

Ultrasonic Power

The level of ultrasonic power is commonly referred to in ultrasonic Watts per litre capacity. For example a 30 litre tank with 600W of ultrasonics will give 20W/litre.

In general, the level of ultrasonic power should not be less than 8W/litre although this can sometimes be reduced for very large tanks.

Ultrawave measure the power of our ultrasonic systems in RMS. This gives the total power of the transducers. Some manufacturers measure the ultrasonic power in “peak to peak” which doubles this value so it is important to compare the same measurements

when purchasing an ultrasonic system.

Contributing Factors

Timer

Different applications will require different cycle times, depending on type and level of contamination.ultrasonic systems incorporate a timer which allows

the cycle time to be programmed to within one minute.

Temperature

Ultrasonic cleaning is commonly most effective at temperatures

between 50 and 65°C. Heat acts as a catalyst for all cleaning

applications but the level of ultrasonic activity will actually begin

to decrease above 80°C.For validated processes where accurate and precise

temperature requirements exist, ultrasonic cleaning systems can incorporate multi temperature programme to ensure that components are not processed outside these parameters.

Detergents

The detergent is an essential component in the overall cleaning process. Different detergents will provide different results depending on the item to be cleaned and the contamination to be removed.

In addition to their cleaning properties, ultrasonic detergents optimise ultrasonic activity by reducing the surface tension of the fluid.

What should I look for in my ultrasonic cleaning system?

Drain valve

The fluid in ultrasonic cleaners needs to be changed on a periodic basis.

A drain valve will allow easy emptying of the tank.

Level Protection

Operating an ultrasonic cleaner without liquid in the tank will cause

damage to the heaters, transducers and tank. A level sensor or float

switch ensures that the system cannot be operated without enough

liquid in the tank.

Basket

It is essential that items being processed in the ultrasonic cleaner do

not rest on the base of the tank. Components should be placed in the

supplied basket or if necessary, suspended within the cleaning fluid.

When an item is in contact with the base of the tank, damage will be

caused and the efficiency of the ultrasonics will be significantly reduced.

Lid

The lid will help to minimise evaporation, aid in the heating of the

cleaning fluid and reduce the noise levels of the ultrasonic cleaner.

Ultrasonic Cleaners Application

Ultrasonic Cleaners in Scientific Labs:
• Eyeglass Frames
• Lab Glassware
• Optical & Contact Lenses
• Pipettes
• Scientific Instruments
• Test Tubes

Ultrasonic Cleaners in Industrial Manufacturing:
• Assemblies
• Gears
• Metal & Plastic Parts
• Precision Bearings
• Relays & Motors
• Switches

Ultrasonic Cleaners in Electronics Manufacturing:
• Capacitors
• Ceramic Substrates
• PC Boards
• Packaging Components
• Quartz Crystals
• SMDs

Ultrasonic Cleaners in Medical & Dental Lab:
• Burs
• Blood Oxygenators
• Cannulae
• Dental Instruments
• Syringe Parts
• Surgical Instruments

Ultrasonic Cleaners in Jewelry Manufacturing:
• Chains
• Charms
• Coins
• Intricate Settings
• Precious Metals & Gemstones
• Watches

Ultrasonic Cleaners in Auto Industry:
• Carburetor
• Castings
• Fuel Injectors
• Machined Parts
• Stamped Parts
• Switches