Retsch AS300 User manual

Operating instructions for sieving machine
type AS300 control
Retsch GmbH, 42781 Haan, Retsch-Allee 1-5, Germany, 07/02/2012 0002

07/02/2012 Retsch GmbH 2
Information on these operating
instructions
The present operating instructions for the model AS300
control analytical sieving machine provide all the neces-
sary information on the headings contained in the table
of contents.
They act as a guide for the reader(s) defined for each
topic necessary for safe use of the AS300 control in ac-
cordance with its intended purpose. Familiarity with the
applicable chapters on the part of each target group of
readers is essential for the safe and proper use of the
equipment.
The present technical documentation has been designed
for use both as a learning tool and a source of reference.
Each chapter is a self-contained unit.
These operating instructions do not contain any instruc-
tions on repairs. Should repairs ever become necessary,
please contact your supplier or talk directly to Retsch
GmbH.

07/02/2012 Retsch GmbH 3
Information on these operating instructions................ 2
Safety .......................................................................... 4
Safety instructions.................................................... 4
Warnings................................................................. 5
Repairs ................................................................... 5
Confirmation............................................................ 5
Technical specifications ............................................... 6
Intended use ........................................................... 6
Emissions ................................................................ 7
Maximum loading ..................................................... 7
Protection systems ................................................... 7
Equipment dimensions .............................................. 7
Base area required ................................................... 7
Transport and assembly ............................................... 8
Packaging................................................................ 8
Transport ................................................................ 8
Temperature fluctuations........................................... 8
Intermediate storage ................................................ 8
Requirements for the assembly site ............................ 9
Assembly / transport fastening................................... 9
Re-using the transport fasteners ................................ 9
Electrical connection ................................................. 9
Operation..................................................................... 10
Operating elements and their use ............................... 10
Installing and tensioning the analytical sieves .............. 11
Operating the AS300 control...................................... 12
Switching on and off ................................................. 12
Start - Interrupt - Stop ............................................. 12
Setting the time ....................................................... 12
Intermittent –continuous operation............................ 13
Memory –saving and calling-up sieve parameters ........ 13
Vibration height in "mm" ........................................... 14
Sieve plate acceleration in "g".................................... 14
Setting the sieve plate acceleration in "g".................... 14
Signal tone for the end of sieving ............................... 14
Operating hours display ............................................ 15
Information on “memory” display ............................... 15
Information on sieve plate acceleration mode .............. 16
Time correction ........................................................ 17
Acceleration guidelines.............................................. 17
Retsch Analytical sieves............................................... 18
Sieve accessories ..................................................... 18
Working instructions.................................................... 19
Sieving aids ............................................................. 19
Sieving material quantities ........................................ 19
Wet sieving .................................................................. 20
Required accessories ................................................ 20
Preparations ............................................................ 20
Operation ................................................................ 20
EasySieve ................................................................... 22
Control, evaluation, documentation. ........................... 22
Serial PC connection ................................................. 22
General ........................................................................ 23
Cleaning.................................................................. 23
Maintenance ............................................................ 23
Replacing fuses ........................................................ 23
Accessories.............................................................. 23
Copyright ................................................................ 23
Safety regulations (table) for the AS300 control from the
chapters.................................................................. 24
Changes.................................................................. 24
Parts subject to wear and tear ..................................... 25
Appendix ............................................... following pages

07/02/2012 Retsch GmbH 4
Safety
The AS300 control is a modern, high-performance prod-
uct manufactured by Retsch GmbH. It incorporates the
latest technology. It is entirely safe in operation when
used for the intended purpose and in accordance with the
present technical documentation.
Safety instructions
You, as the owner/operator must ensure that the persons
who are entrusted to work with the AS300 control:
have read and understood all the regulations contained
in the chapter on safety,
have made themselves familiar, prior to starting work,
with all the operating instructions and regulations rele-
vant to that particular target group,
have complete, immediate and unrestricted access to the
technical documentation for this machine,
new personnel must have familiarised themselves with
the safe use of the AS300 control and its intended pur-
pose before starting work with the machine, either
through verbal instruction by a competent person and /
or with the help of the present technical documentation.
Incorrect operation can result in injuries to persons and
damage to property. You bear the responsibility for your
own safety and that of the rest of your staff.
Ensure that no unauthorised persons have access to the
AS300 control.
As a precaution, have your staff certify in writing that
they have received instruction in the operation of the
AS300 control. A draft for such a form can be found at
the end of the chapter on safety.
We reject herewith any and all claims relating to personal
injury or material damage which results from failure to
comply with the following safety instructions.

07/02/2012 Retsch GmbH 5
Warnings
The following signs are used to warn of hazards:
Personal injuries
Material damage
Repairs
These operating instructions do not contain any repair in-
structions. In the interests of your own safety, repairs
should only performed by Retsch GmbH or an authorised
representative (service technician).
In this case, please notify the following:
Your local Retsch representative
Your supplier
Retsch GmbH direct
Your address for service:
Confirmation
I have read and understood the foreword and the
chapter on safety.
__________________________________
Signature of owner/operator
__________________________________
Signature of service technician

07/02/2012 Retsch GmbH 6
Technical specifications
Machine designation:
AS300 control
Intended use
The AS300 control has been specially designed for analytical
sieves with a diameter of 305 mm (12“) to 315mm. This makes
the available sieving area 2.5 times greater than sieves with a
200 mm diameter. The AS300 control thereby allows the average
sieving times to be shortened.
A further benefit is the very high working quantity of material
to be screened (6 kg) which can be separated in one work proc-
ess. In case of frequently repeated sieve analyses made under the
same conditions, work is considerably simplified by the option of
storing up to 9 parameter combinations direct in the sieving
machine.
To ensure perfectly reproducible results, the AS300 control natu-
rally allows the power frequency independent control drive to
be specified instead of the vibration height. All sieving parameters
are set, displayed and monitored digitally. The amplitude is regu-
lated by a microprocessor-controlled measurement control unit
and is automatically re-adjusted if the loading or voltage changes.
The AS300 control can naturally be calibrated and can be there-
fore deployed as test equipment for quality control action under
DIN EN ISO 9000 ff. As with all "control" devices, the AS300 con-
trol also has an integrated interface.
The sieve can be actuated and adjusted by means of the
EasySieve®evaluation software. EasySieve®displays all sieving
parameters on the screen before and during the sieving process.
This machine is not intended as a production machine nor de-
signed for continuous operation, but rather as laboratory equip-
ment intended for one-shift, 8-hour per day operation.
The AS300 control is suitable for dry sieving of pourable, disperse
products with an input grain of max. 40 mm.
Do not make any modifications to the machine and only use
Retsch approved spares and accessories.
The conformity to the European guidelines declared by
Retsch otherwise loses its validity.
It furthermore leads to the nullification of all warranty
claims.

07/02/2012 Retsch GmbH 7
Emissions
Characteristic noise values :
Noise measurement according to DIN 45635-031-01-KL3
The characteristic noise values are determined primarily by the
set amplitude width or sieve plate acceleration, the number of
sieves deployed and the nature of the material to be screened.
Example :
Sound power level LWA = 64 dB(A)
Workplace-related emission value LpAeq = 59 dB(A)
Operating conditions :
Material to be screened = quartz sand, grain size <1mm, 5
sieves
Amplitude width = 1.5 mm
Maximum loading
Max. quantity of material to be screened = 6 kg
max. sieve stack mass = 10 kg
Protection systems
IP54 or IP20 around the sieve carrier passage
Equipment dimensions
Height: up to approx. 850 mm, Width: 400mm, Depth : 400mm
Weight: approx. 35 kg without sieve stack and
without sieve clamping device
Base area required
400 mm x 400 mm; no safety clearances required.

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Transport and assembly
Packaging
The packaging used is selected with the shipping mode in
mind. It complies with the generally applicable packaging
guidelines.
Please retain the packaging for the duration of the war-
ranty since, in case of a complaint, returning in unsuit-
able packaging can jeopardize your warranty claims.
Transport
During transportation, do not subject the AS300 control
to impacts, jolts or vibrations. The electronic and me-
chanical components could otherwise be damaged.
Temperature fluctuations
In case of wide temperature fluctuations (during ship-
ment by air, for instance), protect the AS300 control
from condensation. The electronic components could
otherwise be damaged.
Intermediate storage
Ensure that the AS300 control is stored in a dry place,
including intermediate storage.

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Requirements for the assembly site
Ambient temperature :
5°C to 40°C
When the ambient temperature exceeds or falls below that
specified, the electrical and mechanical components may be
damaged, and performance data changed to an unknown
extent.
Humidity :
Maximum relative humidity 80% at temperatures up to 31°C,
linear decline down to 50% relative humidity at 40°C
At a higher humidity, the electrical and mechanical compo-
nents may be damaged, and performance data changed to an
unknown extent.
Altitude of assembly site :
Max. 2000 m above sea level
Assembly / transport fastening
SM
Install the AS300 only on a stable laboratory bench to avoid
unpleasant transmission of vibrations.
Undo the hex nut SM with an open-ended spanner until
the sieve disk can be moved freely
Undo the wing screws A (transport fastening) with hex
nuts
Install the appropriate sieve clamping unit
Retain wing screws A with hex nuts (transport fastening)
for transport at a later date.
Re-using the transport fasteners
Screw the hex nuts fully onto the wing screws
Screw the wing screw through the sieve disk into the
housing
Turn the hex nut downwards and tighten with an open-
ended spanner until the sieve disk can no longer move
Mechanical components can be damaged if operated with the
transport fasteners or transported without transport fasten-
ers.
Electrical connection
Refer to the data plate for the voltage and frequency at
which the AS300 control is to be operated.
Ensure that the values shown there correspond to those
for the local power supply.
Use the supplied power cord to connect the AS300 con-
trol to the power supply.
When plugging the power cord into the power source,
use an external fuse corresponding to the local regula-
tions.
Failure to observe the values on the data plate can cause
damage to the electrical and mechanical components.

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Operation
Operating elements and their use
A Cold device plug combination
C Fuse drawer with glass fuses
B Serial connection
D Protective cap for the serial connection
E ON / OFF switch, left bottom
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16
1
PROG –button for calling preset sieving parameters P1-P9 or on and for ending pro-
gramming without storing the parameters.
2
Display memory shows the selected programme P1-P9 or on. If the AS 200 is driven by
the EasySieve®softwear programme ES appears in the display.
3
SET –button for activating the setting mode for the preselected programme positions P1-
P9 and for storing the parameters after programming.
4
▬button reduces the amplitude 0.20 –2.20mm, precision ±0.1mm, or sieve bottom
acceleration in „g“
5
Display amplitude shows the amplitude (2 x amplitude) of 0.20 –2.20mm or sieve bot-
tom acceleration in „g“.
6
+button increases the amplitude, 0.20 –2.20mm, precision ±0.1mm, or sieve bottom
acceleration in „g“.
7
▬button reduces the interval time, 10 –99sec.
8
Display interval shows the preselected interval time, 10 –99sec.
9
+ button increases the interval time, 10 –99sec.
10
Button switches interval operation ON, left LED lights up.
11
Button switchces interval operation OFF, right LED lights up.
12
▬button reduces the sieving time, 1 –99min.
13
Display time shows the preselected sieving time, 1 –99min.
14
+ button increases the sieving time, 1 –99min.
15
START button starts the sieving process and the green LED lights up.
16
STOP button stops and ends the sieving process and the red LED lights up.

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Installing and tensioning the analytical sieves
The AS400 control is suitable for use with analytical sieves
with outer diameters of 305-315mm.
Up to 8 analytical sieves plus base pan can be clamped in.
A clamping unit and cover are available for this purpose (see
the accessories listing).
G
F
H
I
Screw the threaded rods Hinto the sieve disk screws and
lock with the hex nuts I.
Center the selected sieve stack on the sieve disk
Lay the clamping cover F over the threaded rods on the top
sieve.
Tilt the clamping nuts G to slide them over the stand thread
and down to the clamping cover and fasten securely by
hand.
We recommend the use of talcum powder if the base pan sticks
to the smooth surface of the sieve carrier when removing the
sieve stack.
Shorter rods for the sieve clamping unit are available for
clamping in a maximum of 5 analytical sieves and a base pan
(see accessories.

07/02/2012 Retsch GmbH 12
Operating the AS300 control
Switching on and off
E
The main switch E is located at the left front of the AS300 control
under the operating element.
Turn the main switch on
On illuminates in the memory display
1,00 illuminates in the amplitude display
The interval off LED illuminates
Two bars illuminate in the time display (- -)
The AS300 control is now ready for operation, without intermittent
mode, in continuous duty, with a vibration height of 1.00mm.
Start - Interrupt - Stop
5 15 16
Start:
Press START / key 15
The green LED above key 15 illuminates
Display 5 shows the run-up of the machine to the preset value.
During the sieving time, the vibration height or sieve plate accel-
eration are kept constant within the stipulated tolerances.
Interrupt (pause function) :
Press STOP / key 16 once
The red LED above key 16 illuminates
The values remain visible
Press START / key 15
The sieving process is resumed
Stop (standby function) :
Press STOP / key 16 twice
The red LED above key 16 illuminates
The entire display goes out
Activate the LED displays = press key 15 once
New values can now be entered
Press START / key 15 a 2nd time
The function as with Start is executed.
Setting the time
12 13 14
When the AS300 control is switched on, the sieving time is still
undetermined = 2 bars in display 13.
Switch on time 1 –99 min. :
Key 12 reduces the time down to 1 min.
if undershot, two bars appear = undetermined sieving time
Key 14 increases the time up to 99 min.
if overshot, two bars appear = undetermined sieving time

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Intermittent –continuous operation
7 8 9 10 11
When the AS300 control is switched on, intermittent operation is ini-
tially disabled.
Enabling intermittent mode of 10-99 sec. :
Press key 10
The LED above key 10 illuminates
Display 8 shows 10 sec.
Pressing key 9 raises the interval period up to 99 sec.
If 99 sec is overshot, start again with 10 sec.
Key 7 reduces the interval period down to 10 sec.
If 10 sec. is undershot, start again with 99 sec.
Disabling intermittent mode :
Press key 11
The LED above key 11 illuminates
Display 8 is extinguished
Memory –saving and calling-up sieve parameters
2 5 8 10 11 13
The memory function, thus saving or calling-up preselected sieve pa-
rameters, is only available in standby mode. You are able to change
and overwrite program places P1 to P9 at any time.
After the AS300 control has been turned on, display 2shows "on".
The next program place P1 to P9 is reached by pressing the PROG
key. on reappears in the display after program place P9.
on = the sieve parameters 5/8/10-11 and 13 can be freely
set here.
or
P1 to P9 = sieve parameters can be stored and called-up here
Start = sieving process is started with the sieve parameters
stored in program place P1 to P9.
Occupying storage space
Press the PROG key until the required storage place P1-P9
has been reached.
Press the SET key, all displays flash
Set sieve parameter 5/8/10-11/13
The programming mode can be aborted by pressing the PROG button
–the values are not stored.
Press SET button –the values are stored
Flashing of the display stops, the adjusting interlock is activated, the
sieving parameters are stored.
If the AS300 control is actuated with a PC and the "EasySieve®"
sieve software, display 2shows "ES". No manual changes to the sieve
parameters are possible in this mode.

07/02/2012 Retsch GmbH 14
Vibration height in "mm"
A value twice the amplitude is shown as the measured value in dis-
play 5 marked amplitude. We refer to this measured value
throughout these instructions as the vibration height.
When the AS300 control is switched on, the vibration height is
preset to 1.00 mm.
Setting the vibration height from 0.20 –2.20mm :
4 5 6
Reduce :
Key 4 reduces the vibration height down to 0.20 mm
Hold down key 4, after 5 sec. the rapid adjustment function will
commence
If 0.20 mm is undershot, 2.20 mm appears again
Increase :
Key 6 increase the vibration height up to 2.20 mm
Hold down 6, after 5 sec. the rapid adjustment function will com-
mence
If 2.20 mm is overshot, 0.20mm appears again
Sieve plate acceleration in "g"
When the AS300 control is switched on, the vibration height is
preset to 1.00 mm and can be switched to sieve plate accelera-
tion mode by simultaneously pressing and holding down
keys 4+6 for 2s
After switchover, display 5still does not show any values, this
only happens after the START has been pressed.
The display 5 marked as amplitude mm will show a multiple of
the Earth's gravity "g" as the measured value.
( 1g = 9,81m/s2 )
Setting the sieve plate acceleration in "g"
from 1 –approx.17g
Naturally, your AS300 control can only achieve the sieve
plate acceleration at which, in dependence on the inherent fre-
quency, an amplitude of 2.2 mm is not overshot.
4 5 6
Reduce :
Key 4 reduces the sieve plate acceleration down to 1g
Hold down key 4, after 5 sec. the rapid adjustment function
will commence
Increase :
Key 6 increase the sieve plate acceleration up to approx. 17g
Hold down 6, after 5 sec. the rapid adjustment function will
commence
Signal tone for the end of sieving
11 15 16
If the sieving process runs to the end without interruption, the end
is then signalled by an acoustic tone sounding 5 times.
Disabling the signal tone :
Press keys 11 and 16 simultaneously
confirmed by a signal.
Enabling the signal tone :
Press keys 11 and 15 simultaneously
confirmed by a signal.

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Operating hours display
3 9
If the buttons described below are pressed, the complete running
time of the machine in hours and minutes can be displayed.
Displaying the operating hours:
Press buttons 3 and 9 simultaneously and keep pressed
The indication “bS” appears in the „memory“ display.
hhh hh min 16
Passing out of the operating hours:
Press button 16, STOP.
Information on “memory” display
The following abbreviations can appear:
Display
Description
Button combinations
on
Normal mode –all parame-
ters can be adjusted –also
during sieving.
P1 –P9
Calling and indication of
stored programmes.
Press button „PROG“
ES
Operation with software
EasySieve®
Automatic when start-
ing from EasySieve
bS
Operating hours display
Button combination
“SET” and interval time
„+”
S
Softwear version display
Button combination
“SET” and interval time
„ -”

07/02/2012 Retsch GmbH 16
Information on sieve plate acceleration mode
The AS300 control is a throw sieve which allows you to set
both the amplitude and the sieve plate acceleration as
sieving parameters.
Throw sieves such as the AS300 control are generally based
on a spring/mass system which is exited in inherent frequency.
This means that in contrast to machines exited at mains power
frequency which always oscillate at 50 or 60 Hz, varying sieve
frequencies set in here when loaded with different numbers of
sieves and sieve weights. However, the spring/mass system
has been designed in such a way that the inherent frequency
range is always kept somewhere near 50 and 60 Hz.
As long as sieve analyses are only to be compared with each
other or reproduced within the respective inherent frequency
ranges, setting the same amplitudes and sieving times will
naturally produce comparable results.
However, the increasing globalisation of production processes
nowadays often requires sieve analyses made in both mains
power frequency ranges 50/60Hz to be compared with each
other, and naturally also with the results of your AS300 con-
trol exited at inherent frequency. Even if these sieve analyses
are conducted with the same amplitude and sieving time, the
disparate sieve frequencies are likely to adversely affect the
comparability of results at reasonably short sieving times.
The reason for these differences lies in the fact that the essen-
tial parameter in throw sieve analyses is not amplitude, but
rather the sieve plate acceleration, which is crucially influ-
enced by frequency as well as amplitude. Provided that siev-
ing is only carried out at the same frequency, e.g. with the
same mains power frequency, varying the amplitude is natu-
rally the only means of varying the sieve plate acceleration!
In order to take account of these physical facts, your new
AS300 control enables not only the amplitude to be set, dis-
played and regulated, but also the sieve plate acceleration.
The sieve plate acceleration is shown as a multiple of the
Earth's gravity "g" ( 1g = 9.81 m/s2). The functional principle
is based on our German patent No. 19 522 987.
See the chapter on "Operating the AS300 control" and the
paragraph "Sieve plate acceleration" for more details on op-
eration.
Comparative sieve analyses in acceleration mode with direct in-
feed nevertheless require that the sieve plate acceleration of
the comparative machine (e.g. a AS200 control or another
AS300 control) is known.
If the sieve plate acceleration is unknown, our EasySieveR
evaluation software enables you to input comparative data both
much more simply and in a greater scope, thus, for example,
there is also the option of time correction.

07/02/2012 Retsch GmbH 17
Time correction
Our investigations have shown that the switch to specifying the
sieve plate acceleration instead of the amplitude is the
most significant influencing variable when sieving at varying
frequencies. Nevertheless, it is clear that an equal sieving time
at 60Hz will involve 20% more sieve strokes than at 50Hz,
which basically is on a par with an extension to the sieving
time. Especially when short sieving times are selected, we ac-
cordingly recommend that the sieving time is corrected with
the help of EasySieve®
Acceleration guidelines
The relevant specialist textbooks, e.g. "Zerkleinerungs- und
Klassiermaschinen" (Crushers and Classifiers) by Prof. Dr. Karl
Höffl, designate sieve plate acceleration in "g" with the letter K
and describe the relationship between this and the sieving ef-
fect as follows:
K
(„g“)
Movement of charge
Sieve performance
Associated
amplitude at
50 Hz
Associated
amplitude at
60 Hz
1,0
No throw, flow or slip
Very sluggish,
sieve plate clogs up quickly
0.2 mm
0.14 mm
1,5
Gradual lift
Sluggish,
sieve plate clogs up slowly
0.3 mm
0.21mm
1,8
Very flat throw
Very gentle action for material
which is easy to screen
0.36 mm
0.25mm
2,3
Flat to slightly steep
throw
Gentle action for material which is
less easy to screen
0.46 mm
0.32mm
3,5
Steep throw
Brisk action
0.7 mm
0.5 mm
4
Very steep throw
Very brisk action with strong
separation
0.8 mm
0.55 mm
We have added the last two columns to show the associated
amplitudes for the two most common mains power frequencies
in the world.
These particulars should only be regarded as rough values ap-
plicable to small charges, when the material to be screened can
generally move around the sieve plate as discrete grains due to
its distribution.
In the laboratory, however, the pulse transmitted by the sieve
plate are usually muffled by thick layers of charge and the
sieve plate of the analytic sieve itself vibrates. Accordingly,
higher K-factors are required in everyday laboratory practice
than those resulting from the dynamics of individual grains.
Thus for everyday practice, the aforesaid recommendations
need to be multiplied by a factor of 1.5 - 2.

07/02/2012 Retsch GmbH 18
Retsch Analytical sieves
The highest precision for exact results
The accuracy and the reliability of the analysis result are decisively
dependent not only on the sieving machine delivering reproducible
results, but also on the quality of the analytical sieves.
Retsch analytical sieves are high quality measuring instruments for
which only the fabrics and screens which comply with the relevant
standards are used.
Analytical sieves with 305 (12“) and 315mmØ
Sieve plates, frame and labelling executed in compliance with
standards
Tested 5-times with quality certification to DIN ISO, ASTM, BS
On request, with an individual test certificate for control of
test and measuring equipment as per ISO 9000 ff
Sieve plates made of non-rusting wire mesh fabric, 20µm to
125mm
Also available in round or square perforated sheet
Sieve accessories
There are base pans, base pans with discharge, intermediate
pans, intermediate rings and sieve covers available which are
compatible with the different analytical sieves. Sieving aids and
sieve stands complete the range of accessories.
Please refer to our price list for details on how to order the ana-
lytical sieves and the other available accessories.
Tested quality –black on white
RETSCH certificates
Before being delivered, each
sieve is optically gauged and
provided with a works' cer-
tificate.
On request, you receive a
protocol with the acceptance
test certificate which docu-
ments the measurement re-
sults in tabular form and in
graphics, or a calibration
certificate with more detailed
statistics.
Calibration service
As a special service we
offer to calibrate your
analytical sieve. In doing
so, we record all the rele-
vant information for the
sieve according to stan-
dardised gauging methods,
and confirm these in the
requested certificate.

07/02/2012 Retsch GmbH 19
Working instructions
Sieving aids
When dealing with material that is difficult to separate, we rec-
ommend the additional use of sieving aids in the individual sieve
fractions. Depending on the width of the sieve meshing and the
preselected vibration intensity, pearls made of agate, rubber, por-
celain or nylon bristles and Vulkollan cubes may be used. Also re-
fer to the table below.
Ensure that the fabric of the sieve is not overstretched by over-
loading with sieving aids as this would have a detrimental effect
on the precision of your analytical sieve.
Overview table
Sieving aids
Quantity per
sieve or charge
Supplier
Area of use
Caution !!
Rubber pearls
5 pcs, Ø20 mm
RETSCH, Haan
Materials to be screened
are fine, dry,
difficult to separate and
throw sieves are used
When using mechanical sieving aids, there
is the danger that soft materials can disin-
tegrate and fine sieve fabrics can be dam-
aged!
Agate pearls
10 pcs, Ø10 mm
RETSCH, Haan
Hard porcelain pearls
approx. 10gr., Ø2
mm
RETSCH, Haan
Vulkollan cubes
5 pcs, 12x12
RETSCH, Haan
Planetary sieving ma-
chines
Bristles
3 pcs
RETSCH, Haan
Plastic rings
3 pcs, various Ø
Brushes
Manual sieving
Highly dispersed silicic acids
0.5 to 2%
Degussa, Ffm
Materials to be screened
are fine, sticky, fatty
and electrostatically
charged
Check applicability and compatibility before
adding!
- - Aluminium oxide
0.5 to 1%
Degussa, Ffm
- - active carbon
- - talcum
Latex and rubber pow-
der
Remove grease
Materials to be screened
are very fatty
The granularity of the material to be
screened may not be altered by the solvent
used to remove grease or by the tempera-
ture and air used in drying.
Dry
Materials to be screened
are very wet or damp
Guide dry, warm air through the
sieve set
Hygroscopic materials to
be screened
Cleanse with steam
Materials to be screened
are coarse and electro-
statically charged
First sieve of the fine sieve then
the coarse sieve
If contamination from
other mechanical aids,
such as rubber pearls, is
to be avoided
The coarse material functions like a me-
chanical sieving aid (pearls) on the fine
sieves.
Intermittent sieving
RETSCH, Haan
Materials to be screened
are fine, stick easily, or
only fall through the
mesh with difficulty
Intermittent switching is built into the
majority of throw sieves and can be
switched on, if required.
Sieving material quantities
The sieve stack required for sieve analyses is composed of ana-
lytical sieves arranged one above the other, with progressively
larger holes towards the top, plus the base pan.
To ensure fast separation with exact results, the quantity of the
material to be screened should be adapted to the sieve diameter
and the nominal size of the openings.
The relevant standards on sieve analysis state guideline values in
this context.
In the case of sieving processes with only 1 to 3 sieves, we rec-
ommend the use of short threaded rods ( available as accesso-
ries ).
Overly long, protruding rods interfere with the material to be
screened due to their inherent vibration characteristics.

07/02/2012 Retsch GmbH 20
Wet sieving
Target group: Owner, operator
Dry sieving will be possible in the large major-
ity of cases. There are, however, some mate-
rials in which the adhesive forces between the
individual particles can cause difficulties.
These problems can be eliminated by adding
liquid, preferably water, during the sieving op-
eration (in so far as the additives mentioned in
the chapter on “sieving aids” were not suc-
cessful). One pre-condition for wet sieving,
however, is that the substances to be sepa-
rated will not swell, dissolve or otherwise in-
teract with the liquid.
Required accessories
Clamping cover with spray nozzle, matching
the sieve diameter.
Base pan with water drain, matching the
sieve diameter.
Preparations
Position your AS200 control “g” near a water
drain.
Use a hose to connect the spray nozzle in
the clamping cover to a water faucet.
Connect the drain from the base pan with
the drain or a suitable container to receive
the liquid.
Operation
Apply the solid in the form of a suspension.
Set the liquid (water) supply rate so that the
spray just covers the sieve surface com-
pletely.
Using dispersion agents is advisable. They
reduce the surface tension of the sieve liq-
uids.
When dealing with goods which resist form-
ing a slurry or where more exact separation
is required, spray each individual fraction,
one after the other.
Following the sieving process, the fractions
are to be transferred from the individual
sieves to suitable filters (e.g. filter paper)
and dried in a drying cabinet at 80°C.
Then clean the sieves in an ultrasonic bath
and dry them, too, in the drying cabinet
(without the gaskets).
Do not exceed a maximum drying tempera-
ture of 80°C.