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Maintenance
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Assuming constant test conditions, the test result is evaluated based on the per-
forated surfaces of the foils. The perforated surfaces of all foils should have
approximately the same reach and distribution – they are never identical. Con-
sistency of process validations, e.g. for the treatment of medical devices, can only
be ensured through regular foil tests.
To document the test results, you can download a documentation
template here:
https://bandelin.com/folientest/
Here you will also find an application video.
Foils can also be archived if done in a suitable manner (scanning, photos, etc.).
This allows foils to be compared at any time.
Conducting the foil test
1. Fill the oscillating tank to the filling level mark with water and a suitable ultra-
sound preparation, in the concentration specified by the manufacturer.
2. Degas the sonication fluid.
3. Stretch aluminium foil (household foil, 10
μ
m to
25
μ
m thick) over the foil test frame. Depending on
the tank size, it is possible that the frame will pro-
trude outside the tank. Covering the part of the foil
test frame that is covered by the sonication fluid
will be enough.
4. Place the covered foil test frame diagonally in the
centre of the oscillating tank. Fasten it if necessary.
5. Switch on the ultrasound. Sonicate the foil for at least one
minute until visible perforations or holes are produced. With
sturdier foils (thicker or coated ones), the sonication time
may be up to 3 minutes.
6. Switch off the ultrasound. Remove the foil test frame. Remove the aluminium
foil from the foil test frame and allow it to dry.
7. The foil must be perforated, see image. Else, we
recommend having the device checked by the Ser-
vice department at BANDELIN electronic
GmbH & Co. KG: See chapter
.
8. Archive the foil with the test date and serial num-
ber of the ultrasonic bath. The foil test document
template can also be completed and archived.
9. Rinse the oscillating tank thoroughly to remove any
detached foil particles.
Suitable foil test frames can be ordered from BANDELIN electronic
GmbH & Co. KG. The foil test frames are designed for a wide range of tank dimen-
sions. Aluminium foil is also required to conduct the test, but it is not included in
the scope of delivery.
