1 operating principle, 3 obligations of the operator, Safety information and use – FRITSCH LABORETTE 27 User Manual

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2.2.1 Operating principle

In the LABORETTE 27, two different division principles are combined in

one device such that the advantages of both can be optimally used:
The commodity stream - guided by a funnel - impacts on a cone. By

sliding off its lateral surface, an initial division into individual streams

takes place. This process is known as "coning" and is successfully used

mainly when dividing large quantities.
In the case of the LABORETTE 27, the fanned out commodity stream is

led into individual channels at the lower end of the cone surface and col-

lected in glass laboratory bottles.
The relatively high rotational speed of the cone prevents inhomogeneity

in the commodity stream and demixing during apportionment. Through

rotation of the cone, the probability of falling into a certain bottle is

equal for all components of the commodity stream.
Additionally, the divided commodity stream is accelerated outwards

through the centrifugal force of rotation and flows more easily through

the guide channels into the collection bottles. The guide channels inter-

penetrate. The commodity stream is divided up and deposits are

reduced through the sharp lines of separation between the channels.
The high rotational speed of the turning dividing cone leads to an

extremely high division ratio, i.e. each sample consists of a very large

number of single shots. A high division ratio is, however, one of the most

important prerequisites for a good, representative sample division.

2.3 Obligations of the operator

Before using the LABORETTE 27, this manual is to be carefully read and

understood. The use of the LABORETTE 27 requires technical knowledge;

only commercial use is permitted.
The operating personnel must be familiar with the content of the oper-

ating manual. For this reason, it is very important that these persons

actually receive the present operating manual. Ensure that the operating

manual is always near the device.
The LABORETTE 27 may exclusively be used within the scope of applica-

tions set down in this manual and within the framework of guidelines

put forth in this manual. In case of non-compliance or improper use, the

customer assumes full liability for the functional capability of the LABOR-

ETTE 27 and for any damage or injury arising from failure to fulfil this

By using the LABORETTE 27 the customer agrees with this and recognizes

that defects, malfunctions or errors cannot be completely excluded. To

prevent risk of damage to persons or property or of other direct or indi-

rect damage, resulting from this or other causes, the customer must

implement sufficient and comprehensive safety measures for working

with the LABORETTE 27.

Safety information and use

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