XUB Series Digital Ultrasonic Baths

1. What detergents should I use in my ultrasonic cleaner?
This will vary depending on your application. Medical devices should be cleaned using a pH neutral detergent. Industrial cleaning can incorporate more alkali or in some cases more acidic detergents. Special consideration should be made when cleaning aluminium or other soft metals which are more susceptible to pitting when subjected to ultrasonic cavitation.

For information on which detergent you require for your cleaning process please contact Grant on +44 (0) 1763 260 811 .

2. How long do I need to clean my components for?
Cleaning time varies depending on the performance of your ultrasonic bath and the level of contamination present. Different conditions (temperature, ultrasonic power, detergent and detergent dose) will all have an effect on the length of time required to clean a component.

3. How much can I load into my ultrasonic cleaner?
The more instruments placed into an ultrasonic bath, the less effective the cleaning cycle is going to be. It is not advisable to place instruments in the basket so that they overlap as a more effective clean will be generated if all surface areas are openly exposed to the cleaning solution. However, filling a basket so that there is clear space between instruments should lead to an effective cleaning cycle.

4. What service options are available for my ultrasonic cleaner?
Grant Instruments can provide tailored service contracts to suit your specific needs. For more information on the options available, please contact the Grant service department on +44 (0) 1763 260 811 or e-mail service@grant.co.uk

5. Why do I need to degas my ultrasonic cleaner before use?
Gases are present in tap water. To allow optimum ultrasonic activity to occur within the bath these gases need to be removed. Activating the ultrasonics, prior to initiating a cleaning cycle will remove these gases from the fluid. The period taken to degas the fluid can vary depending on the size of the bath and the hardness of the water.

6. How often do I need to change the cleaning solution?
This will vary depending on the cleaning application and the frequency with which the bath is used. When cleaning medical instruments, it is recommended that new solution is added to the bath twice a day - based on an 8 hour day i.e. once every 4 hours. Depending on the convenience and application, industrial ultrasonic tanks may require a fluid change more or less regularly. The cleaning results and fluid in the bath should be monitored for contamination after cleaning and judgment made by the operator on how often the fluid needs to be changed. Please contact Grant for guidance on this.

7. Can I remove items from the ultrasonic tank while it is in operation?
Items should not be removed from the bath during a cycle. To ensure the cleaning process is complete, items should remain in the bath until the cycle has completed. Placing hands in the ultrasonic bath while running a cycle should also be avoided.

8. Should the lid be on my ultrasonic cleaner when in operation?
The lid should be kept on the ultrasonic cleaner while in operation. The lid is for the protection of the operator and in medical applications the patients also. It prevents aerosols generated during the cavitation process from dispersing and contaminating the reprocessing environment. In addition, the lid reduces the noise levels created during the ultrasonic cycle and helps to maintain the heat of the cleaning fluid in the tank.

9. How can I test the level of ultrasonic activity within the bath?
There are a number of recommended tests for establishing levels of ultrasonic activity in the bath. The foil test involves suspending a strip of foil into various locations around the tank. The foil should not touch the base of the tank and should be held in position for around 1 minute. It should then be removed and there should be an even distribution of perforations and small holes on the surface of the foil. Another test requires the use of Brownes soil test strips. These are plastic strips which have been contaminated to simulate the contamination which might affect surgical instruments. After running an ultrasonic cycle the strips should be taken from the bath and all contamination should have been removed. An ultrasonic energy meter can also be used to test the level of ultrasonic activity within the tank.

Please contact Grant for more information on ultrasonic activity testing methods.

10. Why do I need to use a basket in my ultrasonic bath?
A basket should be used in order to protect the base of the ultrasonic tanks from damage. Placing items directly into the tank so that they are in contact with the base can cause damage to the bath. When instruments are in direct contact with the bath, the action of generating ultrasonic activity can cause excessive wear to the base of the tank. Using a Grant ultrasonic bath without a basket will invalidate your warranty. Items should be placed in a stainless steel, mesh basket so that the ultrasonic activity is not significantly reduced.

11. What is a piezo ceramic transducer?
The transducer is used to generate the ultrasonic waves in the fluid. Electrical energy is passed through the transducer which is then converted into ultrasonic energy. When bonded to a tank full of liquid, this ultrasonic energy creates the cavitation process within the bath.

12. Is it important for the liquid to have a low surface tension?
Yes it is. Low surface tension promotes the cavitational activity. Detergents act as surfactants and reduce the surface tension of the liquid in the bath. Surface tension will also reduce as the temperature of the cleaning fluid increases.

13. What temperature is best for ultrasonic cleaning?
This will vary depending on the application but in general higher temperatures lead to better cleaning results.
For industrial cleaning higher temperatures will aid the cleaning process up to around 70oC. Tests have shown that the most effective cleaning occurs between 55 and 65oC. Medical instrument decontamination should not be carried out above 40 degrees C as this can cause proteins and bioburden to coagulate and bake onto the item.

14. What is the resonant frequency of an ultrasonic transducer?
The resonant frequency is the frequency at which the transducer will operate most efficiently. Depending on the type of transducer, this is typically between 30 to 45 kHz.

15. When should a glass beaker be used?
A glass beaker should be placed in a basket and used to hold the items when very small items are being cleaned. Ultrasonic activity will pass through the glass into the liquid within the beaker, meaning that small items placed therein can still be effectively cleaned.

16. Will small or delicate items become damaged in an ultrasonic cleaner?
In general ultrasonic cleaning is a very gentle process. If damage occurs, it is more likely to be caused by the detergent used rather than the action itself. Please contact us for information on detergent selection.

17. Should I put my hands in the fluid when the ultrasonic cleaner is activated?
It is advised that no part of the operator's body be submerged into the fluid during operation of the bath. Ultrasonic energy can cause damage to joint tissue, create discomfort and skin irritation and even lead to long-term arthritic conditions.

18. Can I use water alone in my ultrasonic bath?
Ultrasonic cleaning produces significantly better results when a detergent is used. We do not advise that water alone is used within the bath. The correct detergent aids in the breakdown of decontamination while also reducing the surface tension of the bath and increasing ultrasonic activity.

19. What should I expect to see when I turn on my ultrasonic bath for the first time?
There will be a small amount of surface ripples across the liquid. No foaming will occur as ultrasonic detergents are formulated not to foam. The noise will be higher pitched than normal and will fluctuate until the liquid is degassed. Once this occurs, the noise will reduce and remain at a consistent pitch.

20. How should I clean large, dense metal objects in my ultrasonic bath?
When cleaning large, dense objects it is important that if at all possible they are submerged in the ultrasonic tank at an oblique angle. This allows the energy developed to rebound around the ultrasonic tank maximising the full potential of the cleaner. This is particularly important if the ultrasonic tank has only one radiating face, i.e. the base of the tank.

21.Why does my ultrasonic bath continue to heat beyond the set temperature?
The ultrasonic activity within the tank will increase the temperature by about 10-15°C over an hour period even if the heaters are not in operation. The cavitation creates energy which in turn creates heat.
The machine will turn the heaters off once the temperature is reached but obviously there is no way to cool down the water in the tank and there is no upper temperature cut out. Once the temperature is reached, the following 1 hour operation would see an increase in temperature.