Danfoss BOCK F User manual

AQ449946687878en-000201
F2, F3 F2 NH3, F3 NH3
F4, F5 F4 NH3, F5 NH3
F14/1166, F14/1366 F14/1166 NH3, F14/1366 NH3
F16/1751, F16/2051 F16/1751 NH3, F16/2051 NH3
FX2, FX3
FX4, FX5
FX14/1166, FX14/1366
FX16/1751, FX16/2051
BOCK
®
F/F-NH3
Operating guide
Translation of the original instructions

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About these instructions
Read these instructions before assembly and before using the compressor. This will avoid misunder-
standings and prevent damage. Improper assembly and use of the compressor can lead to serious
or fatal injury.
Observe the safety instructions contained in these instructions.
These instructions must be passed onto the end customer along with the unit in which the compres-
sor is installed.

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Contents Page
1 Safety 4
1.1 Identication of safety instructions
1.2 Qualications required of personnel
1.3 General safety instructions
1.4 Additional safety instructions NH3
1.5 Intended use
2 Product description 6
2.1 Short description
2.2 Name plate
2.3 Type code
3 Areas of application F, F-NH39
3.1 Refrigerants
3.2 Oil charge F
3.3 Oil charge NH3
3.4 Operating limits
4Compressor assembly 11
4.1 Storage and transport
4.2 Setting up
4.3 Maximum permissible inclination
4.4 Pipe connections
4.5 Pipes
4.6 Laying suction and discharge lines
4.7 Operating the shut-off valves
4.8 Operating mode of the lockable service connections
4.9 Drive
4.10 Oil sump heating
5 Commissioning 17
5.1 Preparations for start-up
5.2 Pressure resistance test
5.3 Leak test
5.4 Evacuation
5.5 Refrigerant charge
5.6 Shaft seal
5.7 Shaft seal change
5.8 Start-up
5.9 Avoiding slugging
6 Maintenance 20
6.1 Preparation
6.2 Work to be carried out
6.3 Spare parts recommendation / accessories
6.4 Lubricants / oil
6.5 Decommissioning
7 Technical data F2-F16 22
8 Technical data F2 NH3-F16 NH323
9 Dimensions and connections F 24
10 Dimensions and connections F-NH332
11 Declaration of incorporation 40

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1|Safety
1.2 Qualications required of personnel
INFO! This operating manual describes compressors that are suitable
for both F-gases and for NH3.
Specic information and characteristics for using NH3are
indicated at the corresponding location with the following
symbols:
NH3
NH3
1.1 Identication of safety instructions
DANGER!
WARNING!
CAUTION!
ATTENTION!
INFO!
Indicates a dangerous situation which, if not avoided,
will cause immediate fatal or serious injury.
Indicates a dangerous situation which, if not avoided,
may cause fatal or serious injury.
Indicates a dangerous situation which, if not avoided,
may cause fairly severe or minor injury.
Indicates a situation which, if not avoided,
may cause property damage.
Important information or tips on simplifying work.
WARNING! Inadequately qualied personnel poses the risk of accidents, the
consequence being serious or fatal injury. Work on compressors is
therefore reserved for personnel with the qualications listed
below:
• For example, a refrigeration technician, refrigeration mechatronic
engineer. As well as professions with comparable training, which
enables personnel to assemble, install, maintain and repair refrigeration
and air-conditioning systems. Personnel must be capable of assessing
the work to be carried out and recognising any potential dangers.

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1|Safety
These assembly instructions describe the standard version of the compressor named in the title
and NH3manufactured by Bock. The Bock refrigerating compressor are intended for installation in a
machine (within the EU according to the EU Directives 2006/42/EC Machinery Directive, 2014/68/EU
Pressure Equipment Directive).
Commissioning is permissible only if the compressor has been installed in accordance with these as-
sembly instructions and the entire system into which it is integrated has been inspected and approved
in accordance with legal regulations.
Only the refrigerant specied in these instructions may be used.
Any other use of the compressor is prohibited!
1.5 Intended use
WARNING! The compressor may not be used in potentially explosive
environments!
1.4 Additional safety instructions NH3
NH3ATTENTION! • High toxicity, intense odour (MAK 50 ppm)
• Explosive between 15 and 30 vol. % in the air. Due to the high
ignition energy and temperature, the risk of explosion, however,
is rated as low. So there are no special explosion protection
measures are required.
• However, the national safety regulations, accident prevention
regulations, technical regulations as well as specific regulations
(EN 378 etc.) must be observed.
• NH3steam is lighter than air and therefore disperses upwards.
• All key directives are summarised in the area for the AiF research
project 9404B "Safety of ammonia refrigeration systems".
• NH3corrodes copper materials and non-ferrous metals and is
incompatible with a number of plastics.
• Proof of personnel's specific expertise for installation,
commissioning, operation and service.
1.3 General safety instructions
DANGER! • Refrigerating compressors are pressurised machines and as such
call for heightened caution and care in handling.
The maximum permissible overpressure must not be exceeded,
even for testing purposes.
WARNING! • Risk of burns! Depending on the operating conditions, surface
temperatures of over 60°C on the discharge side or below 0°C on
the suction side can be reached.

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2|Product description
Open type compressors for external drive (V-belt or coupling)
with oil pump lubrication
2.1 Short description
Dimension and connection values can be found in Chapter 9
Based on the F compressor series, a specially modied selection of compressors is
available for use with the refrigerant R 717.
Important differences from the basic compressor F:
Pistons with three-ring assembly
Con-rod with additional oil supply oil to the small end
Valve plate with optimised pressure unit
Shut-off valve with steel connector for welded joints
All connections are designed as compression joints for steel pipes
F14 NH3and F16 NH3with increased oil volume due to the higher base plate
Special oil lling for NH3: Fuchs Reniso KC 68
Short description NH3
F2, F3
F2
Suction
shut-off valve
Cylinder cover
Valve plate
Shaft seal
Shaft end
Compressor housing
Base plate
Discharge shut-off valve
Fig. 1
Oil sightglass

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2|Product description
F4, F5
Dimension and connection values can be found in Chapter 9
F5
F16
F14, F16
Fig. 2
Suction
shut-off valve
Valve plate
Base plate
Name plate
Cylinder cover
Discharge
shut-off valve
Shaft seal
Shaft end
Compressor housing
Fig. 3
Transport eyelet
Discharge shut-off valve
Cylinder cover
Compressor housing
Base plate
Valve plate
Suction
shut-off valve
Leak oil drain hose
Shaft seal
Shaft end
Transport eyelet

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2|Product description
/
F14 1166 NH3 X
Fig. 4
2.2 Name plate (example)
2.3 Type code (example)
¹) X - Ester oil charge (HFC refrigerant R134a, R404A/R507, R407C)
²)Indication only at F14, F16
NH3version
Swept volume ²)
Size
Oil charge ¹)
Series
1
2
3
4
5
6
FX16/2051
BOCK lub E55
19/28
1 Type designation
2 Machine number
3 Rotation speed minimum with a corresponding displacement
4 Rotation speed maximum with a corresponding displacement
5 ND(LP): Max. admissible operating pressure Suction side
HD(HP): Max. admissible operating pressure
High-pressure side
6 Oil type charged at factory
Observe the limit of
application diagrams!
Bock GmbH, Benzstr. 7
72636 Frickenhausen, Germany
BOCK

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3|Areas of application F, F-NH3
The compressors are lled with the following oil type at the factory:
- for R134a, R404A/R507, R407C BOCK lub E55
- for R22 BOCK lub A46
Compressors with ester oil charge (BOCK lub E55 ) are marked with an X in the type designation
(e.g. FX16/2051).
3.1 Refrigerants
• HFKW: R134a, R404A/R507, R407C
• (H)FCKW: R22
NH3:R717
3.2 Oil charge
INFO! For refilling, we recommend the above oil types.
See also chapter 6.4
The oil level must be in the visible
part of the sight glass; damage
to the compressor is possible if
overfilled or underfilled!
ATTENTION!
Fig. 5
max. oil level
min. oil level
The compressors are lled with the following oil type at the factory:
- for R717: Fuchs Reniso KC 68
3.3 Oil charge NH3

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3|Areas of application F, F-NH3
Permissible rotation speeds:
F2, F3: 960 - 1800 rpm
F4, F5: 500 - 1800 rpm
F14, F16: 700 - 1800 rpm
F2 NH3, F3 NH3: 960 - 1500 rpm
F4 NH3, F5 NH3: 500 - 1500 rpm
F14 NH3, F16 NH3: 700 - 1500 rpm
ATTENTION! Compressor operation is possible within the operating limits.
These can be found in Bock compressor selection tool (VAP)
under vap.bock.de. Observe the information given there.
- Max. permissible discharge end temperature: 140°C
- Max. permissible switching frequency: 12x /h
- A minimum running time of 3 min. steady-state condition
(continuous operation) must be achieved.
Avoid continuous operation near the threshold.
For operation with supplementary cooling:
- Use only oils with high thermal stability.
For operation with capacity regulator:
- Continuous operation, when the capacity regulator is activated,
is not permissible and can cause damage to the compressor.
- The suction gas superheat temperature may need to be reduced
or set individually when operating near to the threshold.
- When the capacity regulator is activated, the gas velocity in
the system can not under certain circumstances ensure that
sufcient oil is transported back to the compressor.
When operating in the vacuum range, there is a danger of air
entering on the suction side. This can cause chemical reactions, a
pressure rise in the condenser and an elevated compressed-gas
temperature. Prevent the ingress of air at all costs!
3.4 Operating limits

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4|Compressor assembly
INFO! New compressors are factory-lled with inert gas. Leave this
service charge in the compressor for as long as possible
and prevent the ingress of air. Check the compressor for transport
damage before starting any work.
Setup on an even surface or frame with sufcient load-bearing
capacity. Use all 4 fastening points.
Compressors and drive motors are basically rigid and should be
mounted together on a base frame.
Correct setup of the compressor and mounting of the belt drive are
decisive for running comfort, operating safety and the service life of
the compressor.
Provide adequate clearance for maintenance work.
Provide adequate ventilation for the drive motor.
Do not use in a dusty, damp atmosphere or a combustible
environment.
Fig. 10
Fig. 11
Fig. 12
Fig. 8
F
E
D
C
B
A
1 2
3
4
F
E
D
C
4
3
2
1
A
B
Tol.-Ang. DIN ISO 2768-mK
Ra Rz
Maß Passung
Freigabe
Alternativbezug:
Baumustergeprüft
Teil inaktiv
Lieferantenzeichnung
-
-
K.-Auftrag:
PL:
Zeichnung ungültig
Entwicklungsstand
Teil keine Serie
120
400
±0.5
über 0.5
bis 6
Benzstraße 7 - 72636 Frickenhausen - Germany - www.bock.de
-
-
Unbemaßte Radien:
-
Diese Zeichnung ist unser Eigentum!
Sie darf ohne unsere Genehmigung weder nach-
gebildet, vervielfältigt, oder Dritten Personen zu-
gänglich gemacht werden. Der Nachbau nach
dieser Zeichnung, oder an Hand der nach dieser
Zeichnung hergestellten Gegenstände durch den
Abnehmer oder Dritte ist nicht gestattet.
Wir behalten uns alle Rechte, gemäß DIN ISO 16016
an dieser Zeichnung vor.
Bearb.
Datum
Änderungs-Nr.
Werkstoff:
Ausgangsteil, bzw. Rohteil:
-
-
Gepr.
Name Datum
19.04.
Werkstückkanten
DIN ISO 13715
Ersatz für:
Ersetzt durch:
Erstellt
2010
Geprüft
-
Kurz
Zone
1/x
Oberflächenbehandlung / Härte:
-
Blatt:
Änderungsbeschreibung
400
Benennung:
±0.8
1000
30 6
-
±0.3
120
30
±0.2
Zeichn.-Nr. Teile-Nr.
Oberflächenangaben ISO 1302
x.xxxx-xxxxx.x
Zust.
Gußtoleranzen:
Gewicht: (kg)
±0.1
Maßstab:
1:1
Wasserwaage
für Indesign
Der Lieferant muß sicherstellen, dass die Ware in
einwandfreiem Zustand angeliefert wird (Korrosions-
schutz, Verpackung für sicheren Transport).
Rz 25
Rz 160
s
25
z y x w u t
0,05
Rz 1,6
0,3
0,7
1,6
2
Rz 16
6,3
Rz 63
Rz 6,3
Rz 12,5
F:\user\kurz\3D Sachen\3D Teile\Zeichnungen\Wasserwaage
Transport and suspension unit on the eyebolt (Fig. 9, F14 to F16) or direct on the discharge
line valve (Fig. 8, F2 to F5).
Fig. 9
4.2 Setting up
?
4.1 Storage and transport
Use transport eyelet.
Do not lift manually!
Use lifting gear!
Storage at (-30°C) - (+70°C), maximum permissible relative humidity
10% - 95%, no condensation
Do not store in a corrosive, dusty, vaporous atmosphere or in a com-
bustible environment.
Fig. 7
Fig. 6
ATTENTION! Attachments (e.g. pipe holders, additional units, fastening parts,
etc.) directly to the compressor are not permissible!

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4|Compressor assembly
4.5 Pipes
Pipes and system components must be clean and dry inside and free of scale, swarf and layers of
rust and phosphate. Only use air-tight parts.
Lay pipes correctly. Suitable vibration compensators must be provided to prevent pipes being
cracked and broken by severe vibrations.
Ensure a proper oil return.
Keep pressure losses to an absolute minimum.
4.4 Pipe connections
The pipe connections have stepped internal diameters so that pipes with
standard millimetre and inch dimensions can be used.
The connection diameters of the shut-off valves are designed for maximum
compressor output. The required pipe cross-section must be matched
to the capacity. The same applies for non-return valves.
Fig. 14: Stepped
internal diameters
4.3 Maximum permissible inclination
ATTENTION! Poor lubrication can damage the compressor.
Respect the stated values.
Fig. 13
A A
aa
AA
aa
ATTENTION! Overheating can damage the valve.
Remove the pipe supports from the valve for soldering.
Only solder using inert gas to inhibit oxidation products (scale).
Amax. 30°,
max. 2 minutes
amax. 15°,
continuous
operation

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4|Compressor assembly
4.7 Operating the shut-off valves
4.6 Laying suction and discharge lines
INFO! Proper layout of the suction and discharge lines directly after
the compressor is integral to the system’s smooth running and
vibration behaviour.
ATTENTION! Improperly installed pipes can cause cracks and tears, the result
being a loss of refrigerant.
A rule of thumb:
Always lay the rst pipe section starting from the shut-off valve downwards
and parallel to the drive shaft.
Fig. 15
Rigid
xed point
As short as possible
Valve spindle seal
Before opening or closing the shut-off valve, release the valve spindle seal by approx. ¼ of a turn
counter-clockwise.
After activating the shut-off valve, re-tighten the adjustable valve spindle seal clockwise.
Fig. 16 Fig. 17
loosen
tighten

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4|Compressor assembly
4.8 Operating mode of the lockable service connections
Pipe connection
Fig. 18
Opening the shut-off valve:
Spindle: turn to the left (counter-clockwise) as far as it will go.
—> The shut-off valve is then fully open and the service connection is closed.
The connection which is not lockable is provided for safety devices.
Fig. 19
Opening the service connection
Spindle: ½ - 1 rotation to the right (clockwise).
—> The service connection is then open and the shut-off valve is also open.
The connection which is not lockable is provided for safety devices.
Connection
blocked
Spindle
Spindle Pipe connection
After activating the spindle, generally t the spindle protection cap again and tighten with 14-16 Nm.
This serves as a second sealing feature during operation.
Service connection
closed
Service connection
opened
Connection
open

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4|Compressor assembly
4.9 Drive
The compressors of the F series can be driven by V-belts or directly by shaft couplings.
V-belt:
Proper assembly of belt drive:
- The pulleys of compressor and drive motor must be rmly mounted and in line.
- Only use V-belts with calibrated lengths.
- Select axis spacing, V-belt length and belt pre-tension according to the instructions issued by
the V-belt manufacturer. Avoid belt uttering.
- Check belt pre-tension after running-in time.
Direct drive with shaft coupling:
Direct drive with shaft couplings demands highly precise aligning of compressor shaft and
motor shaft.
Use the Bock shaft couplings „WK“ and observe the enclosed assembly instructions.
CAUTION! Mount suitable safeguards when driving the compressor by means
of V-belts or shaft couplings!
ATTENTION! Faulty alignment results in premature failure of the coupling and
bearing damage!

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4|Compressor assembly
When the compressor is at a standstill, refrigerant diffuses into the lubrication oil of the compressor
housing, depending on pressure and ambient temperature. This reduces the lubrication capacity of
the oil. When the compressor starts up, the refrigerant contained in the oil evaporates out through
the reduction in pressure. The consepuences can be lack of lubrication, foaming and migration of the
oil, which can eventually lead to compressor damage.
To prevent this, the oil can be heated via an oil sump heater.
Operation: Oil sump heater ON at standstill of the compressor.
Oil sump heater OFF during operation of the compressor
Connection:Oil sump heater must be connected via an auxiliary contact (or parallel wired
auxiliary contact) of the motor contactor to a separate electric circuit.
4.10 Oil sump heating
WARNING! The oil sump heater must not be connected to the electrical circuit
of the safety control chain !
Oil sump heater: 230 V – 1 – 50/60Hz, IP65
Type F2 F3 F4 F5 F14 F16
Electrical power
(Watt) 40 60 80 80 140 140
INFO! Same electrical performance even on NH3compressors
NH3

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5|Commissioning
5.1 Preparations for start-up
5.4 Evacuation
INFO! To protect the compressor against inadmissible operating conditions,
high pressure and low pressure pressostats are mandatory on the
installation side.
The compressor has undergone trials in the factory and all functions have been tested. There are
therefore no special running-in instructions.
Check the compressor for transport damage!
First evacuate the system and then include the compressor in the evacuation process.
Relieve the compressor pressure.
Open the suction and discharge line valves.
Evacuate the suction and discharge pressure sides using the vacuum pump.
At the end of the evacuation process, the vacuum should be < 1.5 mbar when the pump is switched off.
Repeat the process as often as is required.
DANGER! Risk of bursting!
The compressor must only be pressurised using nitrogen (N2).
Never pressurise with oxygen or other gases!
The maximum permissible overpressure of the compressor must not
be exceeded at any time during the testing process (see name plate
data)! Do not mix any refrigerant with the nitrogen as this could
cause the ignition limit to shift into the critical range.
5.3 Leak test
Carry out the leak test on the refrigerating plant in accordance with EN 378-2 or a corresponding
safety standard, while always observing the maximum permissible overpressure for the compressor.
5.2 Pressure strength test
The compressor has been tested in the factory for pressure integrity. If however the entire system is
to be subjected to a pressure integrity test, this should be carried out in accordance with EN 378-2
or a corresponding safety standard without the inclusion of the compressor.

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5|Commissioning
CAUTION! Wear personal protective clothing such as goggles and
protective gloves!
Make sure that the suction and discharge line valves are open.
With the compressor switched off, add the liquid refrigerant directly to the condenser or receiver,
breaking the vacuum.
If the refrigerant needs topping up after starting the compressor, it can be topped up in vapour
form on the suction side, or, taking suitable precautions, also in liquid form at the inlet to the
evaporator.
5.5 Refrigerant charge
ATTENTION! Avoid overlling the system with refrigerant!
To avoid shifts in concentration, zeotropic refrigerant blends
must always only be lled into the refrigerating plant in liquid
form.
Do not pour liquid coolant through the suction line valve on
the compressor.
It is not permissible to mix additives with the oil and refrigerant.
5.6 Shaft seal
ATTENTION! Failure to observe the following instructions can cause loss of
refrigerant and damage to the shaft seal!
INFO! The shaft seal seals and lubricates with oil. An oil leakage of
0.05 ml per operating hour is therefore normal. This applies
particularly during the run-in phase (200 - 300 h).
The compressor types F14 and F16 are equipped with a leak oil
drain hose (see chapter 10 and 11). The leak oil is continually
discharged through the leak oil drain hose. To collect the leak oil,
a receptacle is to be provided by the plant operator. Dispose of
the leak oil in accordance with the valid national regulations.
The compressor shaft is sealed to outside using a shaft seal. The sealing element rotates with the
shaft.
The following is especially important to ensuring fault-free operation:
The complete refrigerant circuit must be correctly executed and clean inside.
Heavy shocks and vibrations to the shaft as well as continuous cyclic operation are to be avoided.
The sealing surfaces can stick together during prolonged downtimes (e.g. winter). Therefore, run
the system every 4 weeks for 10 minutes.

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5|Commissioning
As changing the shaft seal involves opening the refrigerant circuit, this is recommended only if the
seal is losing refrigerant. Replacing the shaft seal is described in the spare part kit concerned.
5.7 Shaft seal change
5.8 Start-up
WARNING! Ensure that both shut-off valves are open before starting
the compressor!
Check that the safety and protection devices (pressure switch, motor protection, electrical
contact protection measures, etc.) are all functioning properly.
Switch on the compressor and allow to run for a minimum of 10 min.
Check the oil level by: The oil must be visible in the sightglass.
ATTENTION! If larger quantities of oil have to be topped up, there is a risk of oil
hammer effects. If this is the case check the oil return!
5.9 Avoiding slugging
ATTENTION! Slugging can damage the compressor and cause
coolant to leak.
To prevent slugging:
The complete refrigeration system must be properly designed.
All components must be compatibly rated with each other with regard to output
(particularly the evaporator and expansion valves).
Suction gas superheat at the compressor input should be min. 7 - 10 K. (check the setting
of the expansion valve).
The system must reach a state of equilibrium.
Particularly in critical systems (e.g. several evaporator points), measures are recommended such
as replacement of liquid traps, solenoid valve in the liquid line, etc.
There should be no movement of coolant whatsoever while the compressor is at
a standstill.

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6|Maintenance
Available spare parts and accessories can be found on our compressor selection tool under
vap.bock.de as well as at bockshop.bock.de.
Only use genuine Bock spare parts!
6.3 Spare parts recommendation/accessories
6.2 Work to be carried out
To guarantee optimum operating safety and service life of the compressor, we recommend perfor-
ming service and checking work at regular intervals of time:
Oil change:
- In series plants produced in the factory not mandatory.
- In field installations or operating in the application limit range, first oil change after approx.
100 - 200 operating hours, then approx. every 3 years or 10,000 - 12,000 operating hours.
- for NH3plants: oil change every year or every 5.000 operating hours.
Dispose of old oil according to the regulations, observe national regulations.
Annual checks: Oil level, tightness, running noise, pressures, temperatures, function of auxiliary
devices such as a oil sump heater, pressure switch. Comply with the national regulations!
6.1 Preparation
WARNING! Before starting any work on the compressor:
Switch off the compressor and secure it to prevent a restart.
Relieve compressor of system pressure.
Prevent air from inltrating the system!
After maintenance has been performed:
Connect safety switch.
Evacuate compressor.
Release switch lock.