FRITSCH PULVERISETTE 2 - Manual (Page 24)

6.4 Setting the grinding pressure
NOTICE!
Before commissioning, it is necessary to adjust (zero posi-
tion) the pressure scale (see Ä Chapter 6.5.1 ‘Adjusting’
on page 25).
The contact pressure of the pestle against the wall and bottom of the
mortar must be adjusted in two directions.
The contact pressure is adjusted with the lid and latch closed.
6.4.1 Positioning the pestle against the bottom of the mortar
The desired contact pressure is set by turning the adjusting nut (c), and
its value is read on the scale (d). If the bottom edge of the black
adjusting nut (c) is above the Gap (mm) 0 display, the pestle is lifted from
the mortar according to the number (6 = 66 mm in the illustration). This
is only required for pre-crushing of coarse samples (see Ä Chapter 6.4.3
‘Pre‐crushing settings for coarse samples’ on page 25). For comminution,
the adjusting nut is usually set to a contact pressure [daN Downforce]
between 2.5 and 17.5 daN.
6.4.2 Positioning the pestle against the mortar wall
It is positioned radially in relation to the main rotation of the mortar. The
desired contact pressure is built up by turning the adjusting screw (e). To
do so, turn the screw (e) to the right until the display cylinder is visible
(f). The contact pressure can be read on the display cylinder (f). For most
applications, the lateral contact pressure is set so that the 1st ring or the
2nd ring is visible.
1. Ring visible ~ 16.5 daN (kg)
2. Ring visible ~ 20 daN (kg)
3. Ring visible ~ 23.8 daN (kg)
4. Ring visible ~ 27.3 daN (kg)
Read the grinding pressures as follows:
Using the device
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