IKA A 11 basic - Manual (Page 14)

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The analytical mill A 11 basic may not been used in explosive atmospheres or
under water. Do not crush explosive, toxic or noxious substances. Please observe
the relevant safety instructions and guidelines regarding dust explosions.
Always wear suitable protective equipment when embrittling the mill feed with
coolants (liquid nitrogen or dry ice), (see laboratory guidelines and accident
prevention regulations applicable to the laboratory).
Ensure that pressure does not build up in the grinding chamber (particularly when
using coolants).
Caution: When using liquid nitrogen, you must only screw on the grinding beaker
and begin the grinding process when the liquid nitrogen is completely vaporized.
Caution: Appliance parts may still be extremely cold for some time after cooling
with liquid nitrogen and should only be handled whilst wearing protective
equipment.
The A 11 basic analysis mill is a batch mill that allows for two different grinding
procedures.
The grinding container closes airtight. This means that the loss of ground material
is equivalent to practically zero.
Impact milling:
For useage with hard, brittle grinding material, dried material or material that is
brittle because of cold (for example grain, coffee, etc.).
Here the grinding material is reduced by means of a beating rotor. The grinding
material is thus broken up. The granularity of the final product is determined by the
duration of the grinding, the level to which the container is filled and the physical
properties of the material being processed.
Cutting milling:
For usage with soft, fibrous grinding material (for example hay, paper, etc.).
Here the grinding material is cut by means of a rotating blade. In thise case as well,
the granularity of the final product is determined by the duration of the grinding,
the level to which the container is filled and the physical properties of the material
being processed. Using the cutting method makes it possible to introduce less
energy into the grinding material, which results in less heating up. In this case as
well, because of the closed design, the loss of ground material is equivalent to
practically zero.
Please unpack the equipment carefully and check for any damages. It is important
that any damages which may have arisen during transport are ascertained when
unpacking. If applicable a fact report must be set immediately (post, rail or
forwarder).
The delivery includes:
The analysis mill A 11 basic with the grinding container A 11.5 (effective volume
80 ml), a beater A 11.1 made of stainless steel (1.4034), a set of tools and and an
operating instructions.
The analysis mill can be used for a wide range of applications. The list of grinding
materials given above is not complete. It is possible to expand the range of appli-
cations further by means of grinding experiments with corresponding grinding
procedures and sample preparations.
Impact milling:
The A 11 basic with a beater reduces soft, medium-hard and brittle materials with
a Mohs’ hardness of up to 6 (felsite: 6 Mohs; quartz: 7 Mohs). For greater levels
of hardness, the wear and tear on the pulverization tool is very high and grinding
therefore becomes uneconomical. If the A 11 basic is used for grinding materials
with hardnesses greater than 4 Mohs, the A 11.3 beater, which is more resistant to
wear and tear, must be used. This prevents the sample from being contaminated
by bits of the grinding tool broken off by wear and tear.
Everything that breaks, is dry, and does not have a high fat content can be ground.
Following is a list of substances that can be ground dry:
Grain, barley, corn, malt, pectin, r roasted coffee, bark, roots, nutshells, bones,
ergot, compressed materials, peat, cellulose, pharmaceutical, artificial, fertilizers,
feed materials, spices, resin, potash, seeds, salts, slag.
Tough grinding material must be cooled, for example by adding pulverized dry ice
to the grinding container.
Correct use
Unpacking
Useful facts