Retsch Autofill 50 l User manual

© Retsch GmbH, 42781 Haan, Retsch-Allee 1-5, Germany | 26.04.2022 Version 0002
Manual
Manual
Liquid nitrogen tank Autofill 50 l/150 l
Translation

2
Copyright
© Copyright by
Retsch GmbH
Retsch-Allee 1-5
42781 Haan
Germany

3
Table of Contents
1Notes on the manual............................................................................................................................. 5
1.1 Explanations of the Safety Instructions ............................................................................................. 5
1.2 General Safety Instructions ............................................................................................................... 6
1.3 Repairs............................................................................................................................................... 7
1.4 Confirmation Form for the Managing Operator.................................................................................. 7
1.5 Type Plate Description....................................................................................................................... 8
2Safety and occupational health instructions...................................................................................... 9
2.1 General.............................................................................................................................................. 9
2.2 Safety instructions on the handling of liquid nitrogen...................................................................... 10
2.3 Safety instructions on the handling of liquid nitrogen (Oxygen deficiency)..................................... 10
2.3.1 Dangers ....................................................................................................................................... 10
2.3.2 Causes......................................................................................................................................... 10
2.3.3 Recommendations....................................................................................................................... 10
2.3.4 General conduct in the case of an accident ................................................................................ 11
2.4 Safety instructions on the handling of liquid nitrogen (Cryogenic burns) ........................................ 11
2.4.1 Dangers ....................................................................................................................................... 11
2.4.2 Causes......................................................................................................................................... 11
2.4.2.1 Burns through splashes....................................................................................................... 11
2.4.2.2 Burns through contact.......................................................................................................... 11
2.4.3 Recommendations....................................................................................................................... 11
2.4.4 General rules of conduct for splashes with liquid nitrogen.......................................................... 12
2.4.4.1 To the eyes.......................................................................................................................... 12
2.4.4.2 On the skin........................................................................................................................... 12
2.5 Danger of explosion......................................................................................................................... 12
2.5.1 Dangers ....................................................................................................................................... 12
2.5.2 Causes......................................................................................................................................... 12
2.5.3 Recommendations....................................................................................................................... 12
2.5.4 General conduct in the case of an accident ................................................................................ 12
2.6 Oxygen enrichment.......................................................................................................................... 13
2.6.1 Dangers ....................................................................................................................................... 13
2.6.2 Causes......................................................................................................................................... 13
2.6.3 Recommendations....................................................................................................................... 13
2.7 Surrounding area of the machine .................................................................................................... 13
2.7.1 Rooms.......................................................................................................................................... 13
3Operating the Device .......................................................................................................................... 14
3.1 Views of the device.......................................................................................................................... 14
3.2 Overview table of the parts of the device ........................................................................................ 15
3.3 Technical Data................................................................................................................................. 16
3.4 Vacuum closure and safety device.................................................................................................. 16
3.5 Level Display ................................................................................................................................... 17
3.6 Filling the vessel .............................................................................................................................. 19
3.7 Pressure build-up............................................................................................................................. 20
3.8 Withdrawal of liquid nitrogen............................................................................................................ 20
3.9 Pressure relief.................................................................................................................................. 20
3.10 Transport.......................................................................................................................................... 20
3.11 Maintenance .................................................................................................................................... 21
3.12 Admitting the test pressure.............................................................................................................. 22
3.13 Checking the seat tightness............................................................................................................. 22
3.14 Checking the response pressure..................................................................................................... 22
4Index ..................................................................................................................................................... 23

Notes on the manual
4

Notes on the manual
5
1 Notes on the manual
This operating manual is a technical guide on how to operate the device safely and it contains
all the information required for the areas specified in the table of contents. This technical
documentation is a reference and instruction manual. The individual chapters are complete in
themselves.
Familiarity (of the respective target groups defined according to area) with the relevant chapters
is a precondition for the safe and appropriate use of the device.
This operating manual does not contain any repair instructions. If faults arise or repairs are
necessary, please contact your supplier or get in touch with Retsch GmbH directly.
Application technology information relating to samples to be processed is not included but can
be read on the Internet on the respective device’s page at www.retsch.com.
Changes
Subject to technical changes.
Copyright
Disclosure or reproduction of this documentation, use and disclosure of its contents are only
permitted with the express permission of Retsch GmbH.
Infringements will result in damage compensation liability.
1.1 Explanations of the Safety Instructions
The following warnings in this manual warn of possible risks and damage:
WARNING
W1.0000
Type of danger / personal injury
Source of danger
−Possible consequences if the dangers are not observed.
•Instructions and information on how the dangers are to be avoided.
Serious personal injuries may result from disrespecting the warning notice. There exists an
elevated risk of an accident or severe injury to personnel. Additionally, in continuous text or
action instructions the signal word WARNING is used.
CAUTION
C1.0000
Type of danger / personal injury
Source of danger
−Possible consequences if the dangers are not observed.
•Instructions and information on how the dangers are to be avoided.
Moderate or mild personal injuries may result from disrespecting the safety instruction for
caution. There exists a medium or low risk of an accident or injury to personnel. Additionally, in
continuous text or action instructions the signal word CAUTION is used.
NOTICE
N1.0000
Type of property damage
Source of property damage

Notes on the manual
6
−Possible consequences if the notices are not observed.
•Instructions and information on how the property damages are to be
avoided.
Property damages may result from disrespecting the notice. However, there exists no risk of
an injury to personnel. Additionally, in continuous text or action instructions the signal word
NOTICE is used.
1.2 General Safety Instructions
CAUTION
Read the Operating Manual
Non-observance of these operating instructions
–The non-observance of these operating instructions can
result in personal injuries.
•Read the operating manual before using the device.
•We use the adjacent symbol to draw attention to the
necessity of knowing the contents of this operating
manual.
Target group : All persons concerned with the machine in any form
This machine is a modern, high performance product from Retsch GmbH and complies with the
state of the art. Operational safety is given if the machine is handled for the intended purpose
and attention is given to this technical documentation.
You, as the owner/managing operator of the machine, must ensure that the people
entrusted with working on the machine:
•have noted and understood all the regulations regarding safety,
•are familiar before starting work with all the operating instructions and
specifications for the target group relevant for them,
•have easy access always to the technical documentation for this machine,
•and that new personnel before starting work on the machine are familiarised
with the safe handling of the machine and its use for its intended purpose,
either by verbal instructions from a competent person and/or by means of
this technical documentation.
Improper operation can result in personal injuries and material damage. You are
responsible for your own safety and that of your employees.
Make sure that no unauthorised person has access to the machine.
CAUTION
Changes to the machine
–Changes to the machine may lead to personal injury.
•Do not make any change to the machine and use spare parts and
accessories that have been approved by Retsch exclusively.

Notes on the manual
7
NOTICE
Changes to the machine
–The conformity declared by Retsch with the European Directives will lose
its validity.
–You lose all warranty claims.
•Do not make any change to the machine and use spare parts and
accessories that have been approved by Retsch exclusively.
1.3 Repairs
This operating manual does not contain any repair instructions. For your own
safety, repairs may only be carried out by Retsch GmbH or an authorized
representative or by Retsch service engineers.
In that case please inform:
The Retsch representative in your country
Your supplier
Retsch GmbH directly
Your Service Address:
1.4 Confirmation Form for the Managing Operator
This operating manual contains essential instructions for operating and maintaining the device
which must be strictly observed. It is essential that they be read by the operator and by the
qualified staff responsible for the device before the device is commissioned. This operating
manual must be available and accessible at the place of use at all times.
The user of the device herewith confirms to the managing operator (owner) that
(s)he has received sufficient instructions about the operation and maintenance of
the system. The user has received the operating manual, has read and taken note
of its contents and consequently has all the information required for safe operation
and is sufficiently familiar with the device.
As the owner/managing operator you should for your own protection have your
employees confirm that they have received the instructions about the operation of
the machine.

Notes on the manual
8
I have read and taken note of the contents of all chapters in this operating
manual as well as all safety instructions and warnings.
User
Surname, first name (block letters)
Position in the company
Signature
Service technician or operator
Surname, first name (block letters)
Position in the company
Place, date and signature
Bestätigung
1.5 Type Plate Description
Fig. 1: Type plate marking
1 Instrument name
2 Year of manufacture
3 Article number
4 Serial number
5 Manufacturer’s address
6 CE marking
7 Waste disposal marking
8 Barcode
When making enquiries, please quote the name of the instrument (1) or the article number (3)
and serial number (4) of the instrument.
1
2
3
4
5
6
7
8

Safety and occupational health instructions
9
2 Safety and occupational health instructions
CAUTION
Danger of injury to eyes and skin
Frostbites through liquid nitrogen
–Liquid nitrogen has a temperature of –196 °C and may cause
injuries similar to burns on skin or eye contact or cause frostbite.
•Always use goggles and wear protective gloves when
opening the cooling casing and the grinding jar.
CAUTION
Use of liquid nitrogen
–Retsch GmbH rules out any liability claims that may arise in the
use of liquid nitrogen or similar cooling agents.
•Please observe the safety regulations of the cooling liquid
supplier.
2.1 General
This section summarises the general occupational health and safety guidelines for the handling
of liquid nitrogen.
CAUTION
Handling liquid nitrogen
General hazardous situations
–The following hazardous situations may arise in the handling of liquid
nitrogen: oxygen deficiency situations, cryogenic burns, danger of
explosion, oxygen enrichment
•All users must be informed about the dangers of working with liquid
nitrogen in order to be able to work safely.

Safety and occupational health instructions
10
2.2 Safety instructions on the handling of liquid nitrogen
2.3 Safety instructions on the handling of liquid nitrogen (Oxygen deficiency)
The main components of air according to volumes are as follows:
–Oxygen O2 21 %
–Nitrogen N2 78 %
–Argon Ar 1 %
The gases contained in the atmosphere are not toxic. However, a change in concentration (in
particular changes to the oxygen concentration) may have effects on life and burns. It is
therefore essential for the air breathed in to contain sufficient oxygen (> 19 %).
Humans cannot detect changes in the composition of air within the time that will actually be
necessary because the components are colourless and odourless.
2.3.1 Dangers
A danger of suffocation exists as a result of the normal evaporation of the liquid nitrogen that
pushes out the oxygen in the air. An oxygen deficiency is dangerous and can cause death
through suffocation. The reaction of the organism to oxygen deficiency will differ greatly
depending on the individual. It is not possible to provide precise and generally applicable
information on the symptoms of an oxygen deficiency.
Example: under normal conditions (20° C; 1013 mbars) 1 l liquid nitrogen evaporates to produce
680 l nitrogen gas.
2.3.2 Causes
An oxygen deficiency may arise during the following work or in the following conditions:
–Nitrogen as liquid or gas
–Natural evaporation of liquid nitrogen
–Refilling of liquid nitrogen
–Leaks in containers for liquid or gaseous nitrogen
–Defect in the air feed or outlet
–Tipping over of the container
This list is not complete.
2.3.3 Recommendations
In order to prevent the danger of an oxygen deficiency, the following measures must be taken.
The vessel:
•must be kept in a vertical position.
•must be provided with a suitable insulating lid.
•must be protected from direct sunlight and may not be set up near heat
sources.
•may not be transported in vehicles in filled state.
•must be protected from impact, knocks and rapid movements.
•Ventilate all installation rooms constantly and appropriately.
•Wear protective clothing (suitable gloves, goggles or face protection and
safety shoes).
•Check the oxygen content of the room constantly.
•Always carry an oxygen metre.
•Only trained personnel may work with liquid nitrogen.

Safety and occupational health instructions
11
This list is not complete.
2.3.4 General conduct in the case of an accident
In the case of an accident from oxygen deficiency the following regulations should be observed.
•Secure the surrounding area to avoid any subsequent accidents.
•Act quickly.
•The rescuers must take measures to protect themselves (respiratory protection device).
•Move the injured persons from the hazardous area.
•Observe the company instructions for emergencies.
•Ventilate the rooms affected sufficiently.
•Investigate the cause of the accident.
This list is not complete.
2.4 Safety instructions on the handling of liquid nitrogen (Cryogenic burns)
Liquid nitrogen is very cold (-196 °C).
The surfaces of vessels that were in contact in liquid nitrogen (in particular during the filling
process) may cause skin burns on contact.
2.4.1 Dangers
Cryogenic liquids may:
–bring about burns to the human body
–make specific materials (metal and plastic) that are not suitable for low temperatures brittle
–generate strong misting depending on atmospheric humidity
2.4.2 Causes
There are two types of cryogenic burns:
2.4.2.1 Burns through splashes
When handling samples and in general when handling liquid nitrogen, personnel must protect
themselves from splashes. They can cause cryogenic burns with serious consequential
damage, in particular to eyes and face.
2.4.2.2 Burns through contact
Contact of the skin with cold material causes frostbite or cryogenic burns.
The interior of vessels or the samples may never be touched or held with bare hands.
2.4.3 Recommendations
In order to prevent the danger of burning the following points must be observed:
•Never bring cryogenic liquids in contact with the skin.
•Never touch the cold non-isolated or iced walls of a vessel.
•Wear personal protective equipment (suitable gloves, goggles or face
protection and safety shoes).
•Keep the vessel upright.
•Use suitable material (e.g. metal hose or PTFE hose) to refill.
•Train personnel.
This list is not complete.

Safety and occupational health instructions
12
2.4.4 General rules of conduct for splashes with liquid nitrogen
2.4.4.1 To the eyes
•Rinse eyes with much water for 15 min.
•Follow the company instructions for emergencies.
•Consult a doctor
2.4.4.2 On the skin
•Do not rub.
•If possible remove or loosen clothing.
•Slowly and gradually warm the parts affected.
•Do not apply anything to the burnt area.
•Follow the company instructions for emergencies.
•Consult a doctor.
Both lists are not complete.
2.5 Danger of explosion
2.5.1 Dangers
The evaporation of liquid nitrogen may lead to an overpressure in the vessel.
2.5.2 Causes
An increase in the vessel may be attributable to:
–incorrect set-up (use of a closable lid)
–icing on the neck and on the insulating lid
This list is not complete.
2.5.3 Recommendations
To avoid the danger of explosion:
•Always use suitable insulating lids (pay attention to waste gas opening).
•Observe filling levels to avoid the formation of ice on the insulating lid.
•Set up the vessel in dry and roofed rooms.
•Monitor atmospheric humidity in the installation room.
•Check vessel regularly for the collection of condensed water.
•Check vessel regularly for damage to surface or material damage
This list is not complete.
2.5.4 General conduct in the case of an accident
In the case of an accident from oxygen deficiency the following regulations should be observed.
•Secure the surrounding area to avoid any subsequent accidents.
•Act quickly.
•The rescuers must take measures to protect themselves (respiratory
protection device).
•Move the injured persons from the hazardous area.
•Observe the company instructions for emergencies.

Safety and occupational health instructions
13
•Ventilate the rooms affected sufficiently.
•Investigate the cause of the accident.
This list is not complete.
2.6 Oxygen enrichment
2.6.1 Dangers
Oxygen enrichment may increase the danger of explosion and fire.
2.6.2 Causes
Oxygen may be condensed from the air if liquid nitrogen is used and similarly be liquefied
because the boiling point of oxygen (approx. -183° C) is above that of nitrogen (-196° C).
2.6.3 Recommendations
The following points must be considered in the case of oxygen enrichment:
•Do not smoke.
•Where possible, keep easily inflammable materials away from the vessel.
•Remove all sources of fire (naked flame and light, spark producers, matches,
lighters etc.).
•Ventilate installation rooms constantly and appropriately.
•Clean floor regularly.
•Train personnel.
•Wear personal protective equipment.
•Check oxygen content constantly.
•Always carry an oxygen metre.
This list is not complete
2.7 Surrounding area of the machine
2.7.1 Rooms
The room in which the machine is located must:
•permit operation without danger to the employees
•have a constantly running and appropriate ventilation system
•have a level and non-porous floor that is also able to bear the load of the
vessel
•have safety datasheets on liquid nitrogen visible for all to see
•prevent unauthorised access
•permit the safe filling of the vessel
•permit accessibility to the vessel for inspection, cleaning and maintenance
This list is not complete.

Operating the Device
14
3 Operating the Device
The Autofill 50 l/150 l vessel is a vacuum super-insulated pressure vessel made of corrosion-
resistant stainless steel for storing refrigerated liquid nitrogen in conformance to the European
Pressure Equipment Directive 97/23/EG, Category I module A, with CE marking.
3.1 Views of the device
Fig. 2: Front view Autofill 50 l
Fig. 3: Rear view Autofill 50 l
V1
PSV
CSV
DM
FA
V3
V2
FA
CSV
PSV
ZF
V3
VV
DM
V1
V2
ZF
KS
KS

Operating the Device
15
Fig. 4: Front view Autofill 150 l
3.2 Overview table of the parts of the device
Element
Description
Function
V1
Withdrawal valve
Valve for taking out liquid nitrogen
V2
Pressure build-up valve
Valve for building up working pressure quickly
V3
Waste gas valve
Valve for draining liquid nitrogen
CSV
Overflow valve
Safety valve for the feed line to the CryoMill
DM
Pressure indicator
Gas pressure display
PSV
Dewar flask pressure relief valve
Safety valve 1.3 bar of the Dewar flask
KS
Quick-release clamp
Sealing and attachment of the siphon to the Dewar
flask.
VV
Vacuum closure and safety device
Sealing of high vacuum in the intermediate hollow
space
ZF
Withdrawal hose
Liquid nitrogen supply line to the CryoMill
FA
Level display
Shows the liquid nitrogen level
V1
PSV
CSV
DM
V3
V2
ZF
KS

Operating the Device
16
3.3 Technical Data
Autofill 50 l
Autofill 150 l
Overall height:
80cm
160 cm
Outside diameter:
50cm
50 cm
Overall width:
76cm
76 cm
Immersion depth
58.5cm
122 cm
Neck diameter:
5.0cm
5 cm
Weight empty:
44kg
79 kg
Weight full:
85 kg
204 kg
Geometrical capacity:
49.5 litres
149,5 litres
Stat. rate of evaporation:
2% / day
2% / day
Operating pressure:
max. 1.3 bar
max. 1,3 bar
3.4 Vacuum closure and safety device
Fig. 3: Vacuum closure and safety device
WARNING
The vacuum closure and the safety device protect the vacuum space from positive pressure .
Only the manufacturer’s qualified staff may conduct the re-evacuation .
CAUTION
The protective cap (2) retains the valve insert (1) if excessive pressure builds up in the vacuum
space.
• Do not remove the protective cap (2).
• Protect the valve from heat or cooling because embrittlement can lead to the loss
of operating vacuum.

Operating the Device
17
3.5 Level Display
Fig. 1: Filling level indicator Autofill 50 l
Determination of the tank filling level of Autofill 50 l
• Read the level of Autofill 50 l on the scale of the filling level indicator.
The black area on the scale of the level indicator marks 25% of the remaining content.
• Alternatively, you can also determine the filling level by using a dipstick and compare it with
the filling level curve (see graphic “filling level curve”).
Fig. 2: Filling level indicator Autofill 150 l
Determination of the tank filling level of Autofill 150 l
• Read the filling level of the Autofill 150 l on the digital filling level indicator.
• Alternatively, you can also determine the filling level by using a dipstick and compare it with
the filling level curve (see graphic “filling level curve”).

Operating the Device
18
Fig.5: Filling level curve

Operating the Device
19
3.6 Filling the vessel
CAUTION
A pressure relief must be carried out for safety reasons prior to the removal of the supply line for
the liquid nitrogen.
•Close the tap on the liquid nitrogen tank and start the connected device. Wait until the
pressure has audibly dropped.
CAUTION
The liquid nitrogen tank must not be connected to any other device during the filling process.
Fig. 6: Front view
NOTICE
Damage to the device
Incorrect filling of the tank
–Foreign particles or humidity and thus the formation of ice crystals may
block the pipes and valves of the cooling system, and cause malfunctions.
•Do not remove the lever (HE) when filling.
•Adhere to the specified order when filling the tank.
•Close all valves. (V1, V2, V3)
•Remove the transfer hose (ZF) from the connector (SA).
•Connect the filling pipe to the connector (SA).
•Open the exhaust and overflow valve (V3).
•Open the extraction valve (V1).
•Fill the Dewar until liquid nitrogen escapes from the exhaust and overflow valve (V3).
•Close the extraction valve (V1).
•Close the exhaust and overflow valve (V3).
V1
V3
V2
ZF
SA

Operating the Device
20
3.7 Pressure build-up
•Close the withdrawal valve (V1) and the waste gas / overflow valve (V3).
•Open the pressure build-up valve (V2).
•Watch the pressure indicator (DM).
•Close the pressure build-up valve (V2) as soon as the needle reaches the
red marking or nitrogen comes out of the pressure relief valve (PSV).
Fig. 6: Pressure gauge
3.8 Withdrawal of liquid nitrogen
•Connect the liquid nitrogen line to the device which shall be supplied with
liquid nitrogen and to the connection (SA) of the Autofill.
•Open the filling and withdrawal valve (V1).
•After taking the liquid, close the filling and withdrawal valve (V1) again.
3.9 Pressure relief
•Close the pressure build-up valve (V2).
•Open the waste gas valve (V3).
3.10 Transport
CAUTION
Risks of liquid or gaseous nitrogen
Positive pressure in the vessel
–The introduction of energy during transport can cause a sudden surge in
pressure. Nitrogen is blown off then and this can cause a lack of oxygen,
cryogenic burns, oxygen enrichment and associated risks.
•Make sure the vessel is depressurised before you transport it,
•Remove the siphon and put in the transport plugs.
•Transport the vessel only in an upright position.
•Avoid impacts and vibrations.
•Secure the vessel against falling down, rolling away and damage.
DM