MSE Soniprep 150 Plus - Probe Maintenance and Wear Guidelines; Probe Erosion and Polishing Procedures; Probe Replacement and Cleaning Advice

PROCESSING SAMPLES 16
Sometimes, when the solution is thoroughly aerated, the usual process noise
from the beaker or test tube will stop, i.e. no buzz or vibration will be heard.
Again, this is because there is little transfer of energy. When these conditions
occur, turn the power off for a few seconds and set the probe deeper. Gradually
increase the power and the solution will de-gas. The lower the power setting,
the smaller will be the quantity that may be processed without foaming the
solution. Do not allow the probe to come too close to, or make contact with, the
sides or bottom of glass containers as powdered glass may be formed in the
solution, or breakage may occur. Plastic tubes are more resistant to failure
during sonication, but the insulation properties of plastic may make it difficult to
keep the sample cool.
CAUTION
Please bear in mind that sonication can weaken glass tubes. It is
therefore, advisable that glass tubes used in sonication are not
subsequently centrifuged at high speed as failure of the tube may result.
2.5 Probe Maintenance
In use the probe will erode by the action of cavitation in the liquid. This
dissolution of the metal from the tip of the probe, which occurs, with any metal
during use at high sound intensities is, however, reduced to a minimum by the
use of titanium. The erosion shows itself in concentric rings on the radiating
face. An eroded surface transfers energy less efficiently into the liquid than a
smooth one because of the formation of a zone of cavitation adjacent to the
surface. Energy not transferred into the liquid medium will tend to heat the end
of the probe. Furthermore, erosion continues at an accelerated rate on the
probe tip surface, which is already pitted, thus reducing the useful life of the
probe. For these reasons the tip of the probe should be polished smooth by
means of a very fine emery cloth on a flat surface, but note the following two
cautions.
CAUTION:
a) Probes WEAR OUT, although probes may be polished / reground, the
length of the probe must not be shortened by more than 2mm. PROBES
SHOULD BE REPLACED ANNUALLY OR AS REQUIRED.
b) The transducer/probe mating surfaces must not be cleaned with a non
abrasive cleaner. Should the end require polishing, ONLY A LIQUID NON
ABRASIVE POLISH should be used.
The Soniprep Plus has a red Fault light on the control panel
that will come on when the probe is required to be changed