Wireless grinding jar cover, 12 wet grinding with highly flammable materials – Retsch PM GrindControl User Manual
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Wireless Grinding Jar Cover
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Risk of burning your hands.
It is essential to wear safety gloves when removing or opening the heated grinding
jar.
Pos : 8.23 /00020 BDA Softwar e/20005 PMGC Kapitels ammlung/Ü bersc hriften/1.1 Übersc hriften/11 N ass ver mahlungen mit leic ht e ntz ündlic hen M aterialien @ 0\mod_1216805932680_9.doc @ 2060 @ @ 1
6.12 Wet Grinding with Highly Flammable Materials
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Wet grinding using easily inflammable materials is admissible providing certain
precautions are taken.
When using highly flammable materials as grinding aids, such as for example,
hexane, isopropanol, ethanol, benzene and suchlike, it must be assumed that the
inside of the grinding jar is classifiable as zone 0 with a continually present
explosive mixture.
It must therefore be ensured that the explosive vapours that arise during the
grinding process, in particular because of the heating that occurs then, cannot
escape from the clamped-in grinding jars or reach areas that contain the required
ignition energy.
We therefore urgently recommend that before using such solvents the operator
(employer) of the planetary ball mill should assess the existing hazards and draw
up a coherent explosion protection policy, taking account of local conditions and, if
necessary, providing written definitions of supplementary organisational measures
in an explosion protection document.
In the EU, this procedure is regulated by articles 118 and 118a of EC Directive
89/391/EEC.
Please observe comparable regulations in countries outside the EU.
For this purpose, assume the following prerequisites for the PM100/200:
•
Only type “C” grinding jars are admissible for wet grinding with highly
flammable materials.
•
When selecting solvents, the O-rings’ resistance must be taken into account.
The following are therefore permissible: alcohol (apart from methanol and
ethanol), isopropanol, diisopropylether.
•
Once the grinding jars have been filled, seal them with the clamping rings
included in the scope of supply.
Tighten the camping screws on the clamping ring securely!
Tighten the clamping screws on the clamping ring securely.
Only then are inside pressures up to a max. 5.5 bar permissible.
•
Please note that depending on the size of the grinding jar, the ball filling,
speed and grinding time, the grinding jar can by all means reach a
temperature of over 100°C.
•
The PM100 and PM200 are fitted with a fan which extracts only directly from
the grinding chamber. The extraction volume per hour is more than 20 times
the volume of the grinding chamber. The fan has a standstill monitor with an
acoustic alarm.
•
The air stream produced by the fan during grinding must be conducted to an
extractor.