nord MAXXDRIVE Product guide

B 2050 – en
Explosion-protected industrial gear units
Operating and Assembly Instructions

Explosion-protected industrial gear units – Operating and Assembly Instructions
2 B 2050 en-3023

Documentation
B 2050 en-3023 3
Read document and keep for future reference
Read this document carefully prior to performing any work on or putting the device into operation. It is
essential to read and observe the instructions in this document. They serve as the prerequisite for
smooth and safe operation and the fulfilment of any warranty claims.
Contact Getriebebau NORD GmbH & Co. KG if your questions regarding the handling of the device are
not answered in this document or if you require further information.
The German version of this document is the original. The German document is always decisive. If this
document is available in other languages, this will be a translation of the original document.
Keep this document in the vicinity of the device so that it is available if required.
Use the version of this documentation that is valid for your device at the time of delivery. You can find
the currently valid version of the documentation under www.nord.com.
Please also note the following documents:
• Gear unit catalogues,
• Documentation for the electric motor,
• Documentation for equipment which is attached or provided,
• Special documentation according to details on the name plate.

Explosion-protected industrial gear units – Operating and Assembly Instructions
4 B 2050 en-3023
Documentation
Designation:
B 2050
Part no.:
6053002
Series: Gear units and geared motors
Type series: SK 5207 to SK 15507,
SK 5217 to SK 11217,
SK 5321 to SK 15421,
SK 5418 to SK 12418
Gear unit types: Industrial gear units

Version list
B 2050 en-3023 5
Version list
Title,
Date
Order
number /
Version
Remarks
Internal code
B 2050,
February
2013
6053002 / 06
13
-
B 2050,
Septembe
r 2014
6053002 / 38
14
• General corrections
B 2050,
April 2015
6053002 / 19
15
• General corrections
B 2050
,
March
2016
6053002
/ 09
16
• Revision of ATEX documentation / extension of options,
• Extension of the series,
• New Declarations of Conformity,
• General corrections
B 2050,
May 2017
6053002 /
1817
• Revision
B 2050,
May 2019
6053002 /
1819
• Revision of ATEX documentation,
• Extension of the MAXXDRIVE®XT series,
• New Declarations of Conformity,
• General corrections
B 2050,
October
2019
6053002 /
04419
• Extensive revision of the safety and warning information,
• Removal of the Declaration of Conformity according to
DIN EN 13463-1.
• Revision of the description for Options MS and MF
• SAFOMI option added
• SK 5217 to 11217 added
• Sound Emission chapter added
• Supplements to Service and Maintenance Intervals
chapter
• General corrections

Explosion-protected industrial gear units – Operating and Assembly Instructions
6 B 2050 en-3023
Title,
Date
Order
number /
Version
Remarks
Internal code
B 2050,
November
2020
6053002 /
4620
• Descriptions for Options DB and VL/KL 2/3/4/6 added
• OH option added
• Revision of tables for lubricants and minimum starting
temperatures
• General corrections and amendments
B 2050,
Septembe
r 2021
6053002 /
3921
• Editorial revision
• General corrections and amendments
32535
B 2050,
July 2023
6053002 /
3023
• General corrections and amendments
• Extension of the gear unit types
• Change to name plate
• Additions to the SAFOMI option
• Change to the shrink disc assembly
• Specification of the length of the cooling hoses
• Change to the torque arm sketch
• Assembly note for the input flange (option F1)
• Addition to the oil changing interval for the intermediate
flange (option WX)
• Revision of lubricants
• Removal of EAC Ex
36367
Table 1: Version list B 2050

Copyright notice
B 2050 en-3023 7
Copyright notice
As an integral component of the device described here, this document must be provided to all
users in a suitable form.
Any editing or amendment or other utilisation of the document is prohibited.
Publisher
Getriebebau NORD GmbH & Co. KG
Getriebebau-Nord-Straße 1 •22941 Bargteheide, Germany •http://www.nord.com
Fon +49 (0) 45 32 / 289-0 •Fax [phone]
Member of the NORD DRIVESYSTEMS Group

Explosion-protected industrial gear units – Operating and Assembly Instructions
8 B 2050 en-3023

Table of Contents
B 2050 en-3023 9
Table of Contents
1Safety information.....................................................................................................................................14
1.1 Intended use ....................................................................................................................................14
1.2 Safety information for explosion protection ......................................................................................14
1.2.1 Field of use.........................................................................................................................15
1.2.2 Attachments and equipment...............................................................................................15
1.2.3 Lubricants...........................................................................................................................15
1.2.4 Operating conditions...........................................................................................................15
1.2.5 Radial and axial forces .......................................................................................................16
1.2.6 Assembly, installation and commissioning .........................................................................16
1.2.7 Service and maintenance ...................................................................................................16
1.2.8 Protection against electrostatic charging ............................................................................16
1.3 Applied ignition protection classes according to DIN EN ISO 80079-37 ..........................................17
1.4 Do not make any modifications. .......................................................................................................17
1.5 Performing inspection and maintenance work .................................................................................17
1.6 Personnel qualification.....................................................................................................................17
1.7 Safety for particular activities ...........................................................................................................17
1.7.1 Check for transport damage ...............................................................................................17
1.7.2 Safety information for installation and maintenance ...........................................................18
1.8 Hazards............................................................................................................................................18
1.8.1 Hazards when lifting ...........................................................................................................18
1.8.2 Hazards due to rotating parts .............................................................................................18
1.8.3 Danger on entry..................................................................................................................18
1.8.4 Hazards due to high or low temperatures...........................................................................19
1.8.5 Hazards due to lubricants and other substances................................................................19
1.8.6 Hazards due to noise..........................................................................................................19
1.8.7 Hazards due to pressurised coolants .................................................................................19
2Description of gear units ..........................................................................................................................20
2.1 Gear unit types and type designations .............................................................................................20
2.2 Name plate.......................................................................................................................................25
3Transport, storage, assembly ..................................................................................................................27
3.1 Transporting the gear unit................................................................................................................27
3.1.1 Transport of standard gear units.........................................................................................28
3.1.2 Transport of gear units with motor adapter.........................................................................29
3.1.3 Transport of gear units with auxiliary drives or first stage gear units (Option: WG, WX) ....30
3.1.4 Transport of gear units with V-belt drives ...........................................................................31
3.1.5 Transport of agitator version gear units..............................................................................32
3.1.6 Transport of gear unit with motor swing base or base frame..............................................33
3.2 Storage and downtimes ...................................................................................................................34
3.2.1 General measures ..............................................................................................................34
3.2.2 Storage and downtimes in excess of 3 months ..................................................................34
3.2.3 Storage and standstill periods of more than 9 months........................................................34
3.3 Checking the version........................................................................................................................35
3.4 Preparing for installation ..................................................................................................................36
3.4.1 Check for damages ............................................................................................................36
3.4.2 Remove corrosion protection agents ..................................................................................36
3.4.3 Check rotational direction ...................................................................................................36
3.4.4 Check ambient conditions ..................................................................................................36
3.4.5 Installing the oil reservoir tank (Option OT) ........................................................................36
3.4.6 No-seal adapter for vertical gear units (option : SAFOMI)..................................................36
3.5 Installing the gear unit......................................................................................................................37
3.6 Installation of a hub on solid shaft (option: V, L) ..............................................................................38
3.7 Assembly of gear units with hollow shaft (option A, EA) ..................................................................40
3.7.1 Fitting a hollow shaft with fastening element (option B)......................................................41
3.7.2 Fitting a hollow shaft with shrink disc (Option: S) ...............................................................42
3.8 Installing a flange version gear unit (Option: F, FK, VL2/3/4/5, KL2/3/4)..........................................45
3.8.1 Agitator version (Option: VL2, KL2)....................................................................................45
3.8.2 Agitator version with Drywell (Option: VL3, KL3)................................................................46
3.8.3 Agitator version with True Drywell (Option: VL4, KL4)........................................................46

Explosion-protected industrial gear units – Operating and Assembly Instructions
10 B 2050 en-3023
3.8.4 Extruder flange version (Option: VL5) ................................................................................46
3.8.5 Agitator version with True Drywell and foot mounting (Option: VL6, KL6)..........................47
3.9 True Drywell version gear units (Option: VL4, KL4, VL6, KL6, DRY)...............................................47
3.10 Motor base frame (Option: MF)........................................................................................................48
3.11 Motor swing base (Option: MS)........................................................................................................49
3.12 Installing the cover cap, air baffle (Option: H, H66, FAN, MF.., MS…).............................................50
3.13 Fitting a standard motor (option IEC, NEMA, SAFOMI, F1) .............................................................50
3.13.1 Fitting a motor with standard claw coupling (option IEC, NEMA)........................................52
3.13.2 Fitting a motor with standard claw coupling (option SAFOMI) ............................................53
3.14 Installing the drive coupling..............................................................................................................53
3.14.1 Dog coupling.......................................................................................................................53
3.14.2 Turbo coupling....................................................................................................................53
3.14.3 Dog coupling.......................................................................................................................54
3.15 Installing the output coupling............................................................................................................54
3.16 Connecting a cooling coil (option CC)..............................................................................................55
3.17 Installation of an external cooling system (Option: CS1-X, CS2-X)..................................................57
3.18 Installing a fan (Option: FAN-A, FAN-R) ..........................................................................................58
3.19 Installation of the lubricant circulation (Option: LC, LCX).................................................................59
3.20 Gear unit monitoring sensors (option: MO) ......................................................................................59
3.21 Attaching the temperature sticker.....................................................................................................59
3.22 Installing the torque arm (option D, ED, MS)....................................................................................60
3.23 Connecting the oil heater (Option: OH)............................................................................................62
3.24 Subsequent painting ........................................................................................................................62
4Commissioning .........................................................................................................................................63
4.1 Checking the oil level .......................................................................................................................63
4.2 Activating the vent............................................................................................................................63
4.3 Process heat due to hollow output shaft ..........................................................................................64
4.4 Lubricant circulation (Option: LC, LCX)............................................................................................65
4.5 Gear unit cooling with fan (Option: FAN-A, FAN-R) .........................................................................66
4.6 Cooling coil (Option: CC) .................................................................................................................67
4.7 External cooling system (option CS1-X, CS2-X) ..............................................................................68
4.7.1 Oil / water cooler (Option: CS1-X) ......................................................................................68
4.8 Oil heater (Option: OH) ....................................................................................................................69
4.9 Temperature monitoring (Option: PT100) ........................................................................................69
4.10 Backstop/Auxiliary drive (Option: R, WX).........................................................................................70
4.11 Temperature measurement..............................................................................................................73
4.12 Test run............................................................................................................................................74
4.13 Checklist ..........................................................................................................................................75
4.13.1 Mandatory...........................................................................................................................75
4.13.2 Optional ..............................................................................................................................76
5Service and maintenance .........................................................................................................................77
5.1 Inspection and maintenance intervals..............................................................................................77
5.2 Service and maintenance work ........................................................................................................80
5.2.1 Visual inspection for leaks ..................................................................................................80
5.2.2 Check for running noises....................................................................................................80
5.2.3 Check fan and spaces between the ribs (Maxxdrie XT) (Option: FAN-A, FAN-R)..............81
5.2.4 Cleaning the heat exchanger (Option: CS2-X) ...................................................................81
5.2.5 Device category 2D: Cleaning the cover cap (Option: H) and the motor adapter (Options:
IEC, NEMA)........................................................................................................................81
5.2.6 Oil level...............................................................................................................................81
5.2.6.1 Oil level screw 82
5.2.6.2 Oil inspection glass/oil level glass (Option: OSG), Oil level indicator (Option: OST) 83
5.2.6.3 Oil dipstick (Option: PS) 83
5.2.6.4 Oil level tanks (Option: OT) 83
5.2.6.5 Checking the leak indicator (Option: VL3, KL3 with Drywell) 84
5.2.6.6 Auxiliary drive (option WX), first-stage gear unit (option WG), fluid coupling 84
5.2.6.7 No-seal adapter for vertical gear units (option SAFOMI) 85
5.2.7 Visual inspection of the rubber elements of the elastic torque arm (Option: ED)................85
5.2.8 Visual inspection of cables .................................................................................................86
5.2.8.1 Piping (Option: LC, LCX, OT) 86
5.2.8.2 Hose lines (Option: LC, LCX, CS1-X, CS2-X, OT) 86

Table of Contents
B 2050 en-3023 11
5.2.9 Oil filter (Option: CS1-X, CS2-X, LC/LCX)..........................................................................86
5.2.10 Remove dust ......................................................................................................................86
5.2.11 Oil change ..........................................................................................................................86
5.2.12 Checking the cooling coil for deposits (Option: CC) ...........................................................87
5.2.13 Cleaning or replacing the vent............................................................................................88
5.2.13.1 Vent filter (Option: FV) 88
5.2.13.2 Cellulose filter (Option: EF) 88
5.2.13.3 Drying agent filter / Wet air filter (Option: DB) 88
5.2.13.4 Pressure venting (Option: DR) 90
5.2.14 Replacing the shaft sealing ring..........................................................................................90
5.2.15 Re-lubrication of bearings in the gear unit ..........................................................................91
5.2.16 Re-lubricating the bearing in the output flange (Option: VL2/3/4/6, KL2/3/4/6)...................91
5.2.17 Check the gear unit monitoring (only for 2G / 2D) ..............................................................92
5.2.17.1 Resistance thermometer 92
5.2.17.2 Pressure switch 92
5.2.18 Inspection cover .................................................................................................................93
5.2.19 General overhaul ................................................................................................................94
6Disposal .....................................................................................................................................................96
7Appendix....................................................................................................................................................97
7.1 Versions and mounting position .......................................................................................................97
7.1.1 Parallel gear units...............................................................................................................97
7.1.2 Helical bevel gear unit ........................................................................................................97
7.2 Standard positions of the oil drain, vent and oil level .......................................................................98
7.3 Lubricants ......................................................................................................................................116
7.3.1 Roller bearing greases .....................................................................................................116
7.3.2 Gear oils ...........................................................................................................................117
7.3.3 Minimum starting temperatures ........................................................................................118
7.3.4 Lubricant quantities ..........................................................................................................119
7.4 Screw tightening torques................................................................................................................119
7.5 Tolerances for bolting surfaces ......................................................................................................120
7.6 Troubleshooting .............................................................................................................................120
7.7 Leakage and leak-tightness ...........................................................................................................122
7.8 Noise emissions.............................................................................................................................122
7.9 Declaration of Conformity...............................................................................................................123
7.9.1 Explosion protected gear units and geared motors, Category 2G and 2D........................123
7.9.2 Explosion protected gear units and geared motors, Category 3G and 3D........................124
7.10 Repair information..........................................................................................................................125
7.10.1 Repairs .............................................................................................................................125
7.10.2 Internet information...........................................................................................................125
7.11 Warranty ........................................................................................................................................125
7.12 Abbreviations .................................................................................................................................125

Explosion-protected industrial gear units – Operating and Assembly Instructions
12 B 2050 en-3023
List of illustrations
Figure 1: MAXXDRIVE®XT 2-stage helical bevel gear unit .................................................................................. 22
Figure 2: Name plate............................................................................................................................................. 25
Figure 3: Transport of standard gear unit .............................................................................................................. 28
Figure 4: Transport of gear units with motor adapter............................................................................................. 29
Figure 5: Transport of gear units with auxiliary drives or first stage gear units ...................................................... 30
Figure 6: Transport of gear units with V-belt drives ............................................................................................... 31
Figure 7: Transport of agitator version gear units.................................................................................................. 32
Figure 8: Transport of gear unit with motor swing base or base frame.................................................................. 33
Figure 9: Example of a simple pulling device ........................................................................................................ 38
Figure 10: Permissible application of force to drive and driven shafts................................................................... 39
Figure 11: Applying lubricant to the shaft and the hub........................................................................................... 40
Figure 12: Assembly and disassembly of the fixing element (schematic diagram)................................................ 41
Figure 13: Fixing element (example) ..................................................................................................................... 42
Figure 14: Machine shaft assembly for special hollow shafts with shrink discs ..................................................... 43
Figure 15: Fitted shrink disc................................................................................................................................... 44
Figure 16: VL2 Option ........................................................................................................................................... 45
Figure 17: Option VL3/KL3 and VL4/KL4 .............................................................................................................. 46
Figure 18: Option VL6/KL6 .................................................................................................................................... 47
Figure 19: Schematic diagram (Option: DRY) ....................................................................................................... 47
Figure 20: Centre of gravity of motor..................................................................................................................... 51
Figure 21: Fitting the coupling to the motor shaft................................................................................................... 52
Figure 22: Fusible plug with separate mechanical switch...................................................................................... 54
Figure 23: Cooling cover with cooling coil fitted (schematic diagram) ................................................................... 56
Figure 24: Industrial gear unit with CS1-X and CS2-X cooling systems ................................................................ 58
Figure 25: Hydraulic plan of industrial gear units with CS1-X and CS2-X cooling systems ................................... 58
Figure 26: Temperature sticker position for helical and bevel helical gear units.................................................... 60
Figure 27: Permissible installation tolerances of the torque arm (option D and ED) (schematic diagram) ............ 61
Figure 28: Activation of the pressure vent ............................................................................................................. 64
Figure 29: Industrial gear unit with back stop (schematic diagram) ....................................................................... 70
Figure 30: ATEX labelling...................................................................................................................................... 73
Figure 31: Temperature sticker.............................................................................................................................. 74
Figure 32: Checking the oil level with a dipstick .................................................................................................... 82
Figure 33: Checking the oil level with an oil dip-stick............................................................................................. 83
Figure 34: Illustration air space.............................................................................................................................. 85
Figure 35: Vent filter (Option FV)........................................................................................................................... 88
Figure 36: Cellulose filter (Option EF) ................................................................................................................... 88
Figure 37: Drying agent filter, example version ..................................................................................................... 89
Figure 38: Installing the drying agent filter............................................................................................................. 89
Figure 39: MSS7 seal ............................................................................................................................................ 90
Figure 40: Examples of inspection covers............................................................................................................. 93
Figure 41: Helical gear unit installation positions with standard mounting surface ................................................ 97
Figure 42: Bevel gear unit installation positions with standard mounting surface.................................................. 97
Figure 43: Numbering of oil screw holes on SK 5207 – SK 10507 ...................................................................... 105
Figure 44: Numbering of oil screw holes on SK 11207 – SK 15507 .................................................................... 111
Figure 45: Numbering of oil screw holes on SK 5217 – SK 11217 ...................................................................... 115
Figure 46: Declaration of Conformity for Category 2G / 2D, labelling according to DIN EN ISO 80079-36 ......... 123
Figure 47: Declaration of Conformity for Category 3G / 3D, labelling according to DIN EN ISO 80079-36 ......... 124

List of tables
B 2050 en-3023 13
List of tables
Table 1: Version list B 2050..................................................................................................................................... 6
Table 2: Gear unit overview MAXXDRIVE®Standard – Parallel gear units........................................................... 20
Table 3: Gear unit overview MAXXDRIVE®Standard – Right-angle gear units..................................................... 20
Table 4: Gear unit overview MAXXDRIVE®XT – Right-angle gear units .............................................................. 20
Table 5: Gear unit overview MAXXDRIVE®XD – Parallel gear units .................................................................... 21
Table 6: Gear unit overview MAXXDRIVE®XJ – Right-angle gear units............................................................... 21
Table 7: Gear unit overview MAXXDRIVE®special version .................................................................................. 21
Table 8: Versions and options ............................................................................................................................... 24
Table 9: IEC and NEMA motor weights ................................................................................................................. 51
Table 10: Transnorm motor weights ...................................................................................................................... 51
Table 11: Oil spaces as delivered.......................................................................................................................... 63
Table 12: Back stop lift-off speeds SK 5..07 – SK 10..07 ...................................................................................... 71
Table 13: Back stop lift-off speeds SK 11..07 – SK 15..07 .................................................................................... 72
Table 14: Back stop lift-off speeds SK 5..17 – SK 11..17 ...................................................................................... 73
Table 15: Mandatory checklist for commissioning ................................................................................................. 75
Table 16: Optional checklist for commissioning..................................................................................................... 76
Table 17: Inspection and maintenance intervals.................................................................................................... 78
Table 18: Grease quantities for re-greasing the lower output shaft bearing .......................................................... 92
Table 19: Materials ................................................................................................................................................ 96
Table 20: Position of housing options on oil screw holes (standard installation positions) .................................... 99
Table 21: Roller bearing greases......................................................................................................................... 116
Table 22: Gear oils .............................................................................................................................................. 117
Table 23: Minimum starting temperatures for mineral oils (guideline values for the ambient temperature)......... 118
Table 24: Minimum starting temperatures for synthetic oils (guideline values for the ambient temperature)....... 118
Table 25: Screw tightening torques ..................................................................................................................... 119
Table 26: Overview of malfunctions..................................................................................................................... 121
Table 27: Definition of leakage according to DIN 3761........................................................................................ 122

Explosion-protected industrial gear units – Operating and Assembly Instructions
14 B 2050 en-3023
1 Safety information
1.1 Intended use
These gear units are used to transmit rotary movements. They convert velocity and torque. They are
intended for use as part of a drive system in commercially used plant and machinery. The gear units
must not be operated until it has been established that the plant or machinery can be safely operated
with the gear unit. Suitable protective measures must be provided if failure of a gear unit or a geared
motor could result in a risk to persons. The plant or machinery must comply with local legislation and
directives. All applicable health and safety requirements must be met. In particular, the Machinery
Directive 2006/42/EC and UKCA "Supply of Machinery (Safety) Regulations 2008" must be especially
observed in the relevant areas of application.
The gear units are suitable for use in explosion hazard areas according to the category stated on the
name plate. For the category stated on the name plate, they comply with the explosion protection
requirements of the 2014/34/EU and the "Equipment and Protective Systems Intended for Use in
Potentially Explosive Atmospheres Regulations 2016: Great Britain" directives. The gear units may only
be operated with components which are intended for use in explosion hazard areas. During operation,
no mixture of atmospheres with gases, vapours and aerosols (Zone 1 or 2, IIG labelling), and dusts
(Zone 21 or 22, IID labelling) may be present. In case of a hybrid mixture, the approval of the gear unit
is void.
Structural modifications to the gear units are not permitted and result in the approval for the gear unit
becoming void.
The gear units may only be used according to the information in the technical documentation from
Getriebebau NORD GmbH & Co. KG. Damage to the gear unit may result if the gear unit is not used as
intended and according to the information in the operating and installation manual. This may also result
in personal injury.
The base or the gear unit mount must be appropriately dimensioned for the weight and torque. All of the
fastenings provided must be used.
Some gear units are equipped with a cooling coil/cooling system. These gear units may only be operated
if the cooling circuit is connected and in operation.
1.2 Safety information for explosion protection
The gear units are suitable for use in explosion hazard areas. The following information must be
observed in order to ensure adequate explosion protection.
Note all technical data stated on the name plate and comply with them. Observe the special
documentation stated in field "S" of the name plate as well as instructions for equipment and
attachments.

1 Safety information
B 2050 en-3023 15
1.2.1 Field of use
• Gear units must be properly designed. Overloads may result in breakage of components. This may
cause sparks. Carefully fill in the enquiry form. Getriebebau NORD GmbH & Co KG designs gear
units according to the details in the enquiry form. Please note the information for gear unit selection
in the enquiry form and in the catalogue.
• Explosion protection only applies for areas which correspond to the device category and the type of
explosive atmosphere according to the labelling on the type plate. The type of gear unit and all
technical data must comply with the planning details for the plant or machinery. If there are several
operating points, the maximum drive power, torque or speed must not be exceeded in any operating
point. The gear unit may only be operated in the installation position which complies with the version.
Carefully check all details on the type plate before installing the gear unit.
• All work, e.g. transportation, storage, installation, electrical connection, commissioning, servicing and
maintenance must be performed in a non-explosive atmosphere.
• The atmospheric conditions, in which the drive is commissioned, must be within an ambient pressure
range from 80 kPa to 110 kPa and an oxygen content of approx. 21 % according to DIN EN ISO
80079-36.
1.2.2 Attachments and equipment
• Gear units with a cooling system for oil cooling must not be commissioned without lubricant cooling.
The function of the lubricant cooling must be monitored. If the permissible temperature is exceeded,
the drive must be shut down. Check for leaks at regular intervals.
• Equipment attached to the gear unit such as couplings (that can be mounted on input and output
shafts), pulleys, cooling systems, pumps, sensors, etc., as well as drive motors must also be suitable
for use in the zone with an explosive atmosphere. The ATEX labelling must conform to the details of
the system and/or machine design.
• Couplings for the IEC or NEMA adapters described in this manual have no separate ATEX labelling.
1.2.3 Lubricants
• Unsuitable oils can cause an explosion risk. Therefore only use oils which correspond with the details
on the name plate. Recommended lubricants can be found in the appendix to these operating and
installation instructions.
1.2.4 Operating conditions
• If the gear unit is equipped with a back stop, note the minimum speed for releasing the back stop as
well as the maximum speed. Gear units with a back stop on the drive shaft may only be operated
with a minimum drive shaft speed of 900 min-1. Speeds which are too low cause increased wear and
temperature increases. Excess speeds will damage the back stop.
• If the gear unit is exposed to direct sunlight or comparable radiation, an installation-specific heat
balance examination of the gear unit must be carried out by Getriebebau NORD. Impermissible
temperatures are very likely without this validation.
• Even small changes to the installation conditions can have a significant effect on the temperature of
the gear unit. Gear units with temperature class T4 or with a maximum surface temperature of 135 °C
or less must be provided with a temperature label. The dot in the middle of the temperature label
turns black if the surface temperature is too high. Take the gear unit out of service immediately if the
dot has turned black.

Explosion-protected industrial gear units – Operating and Assembly Instructions
16 B 2050 en-3023
1.2.5 Radial and axial forces
• Drive and driven elements may only be subjected to the maximum permitted radial forces FR1 and
FR2 and axial forces FA2 indicated on the name plate (see Section 2.2 "Name plate").
• Observe the correct tension, particularly for belts and chains.
• Additional loads due to unbalanced hubs are not permitted.
1.2.6 Assembly, installation and commissioning
• Incorrect installation results in stresses and impermissibly high loads. This causes increased surface
temperatures. Note the installation and assembly instructions in these operating and installation
instructions.
• Before commissioning, carry out all of the checks which are prescribed in these operating and
maintenance instructions in order to detect faults which could increase the risk of explosion in good
time. Do not commission the gear unit if abnormalities are found during the checks. Contact
Getriebebau NORD.
• For gear units with temperature class T4 or with a maximum surface temperature of less than 200 °C,
carry out a measurement of the surface temperature of the gear unit before commissioning. Take
the gear unit out of service if the measured surface temperature is too high.
• The gear unit housing must be earthed in order to prevent electrostatic charging.
• Defective lubrication causes temperature increases and sparks. Check the oil level before
commissioning.
1.2.7 Service and maintenance
• Perform all of the inspection and maintenance work specified in these operating and installation
instructions with great care, in order not to increase the risk of explosion due to functional faults and
damage. The drive must be shut down if any abnormalities are detected. Contact Getriebebau NORD.
• Defective lubrication causes temperature increases and sparks. Check the oil level at regular
intervals according to the details in these operating and installation instructions.
• Dust and dirt deposits cause temperature increases. Dust may also be deposited inside covers which
are not dust-proof. Remove deposits at regular intervals according to the details in these operating
and installation instructions.
1.2.8 Protection against electrostatic charging
• Non-conducting coatings, or low pressure hoses may become electrostatically charged. Sparks may
be produced on discharge. Such components must not be used in areas in which processes that
cause charging are to be expected. Oil reservoir tanks may only be located in areas with the gas
group IIC.
• Having a suitable, electrostatically tested paint finish, the gear units are designed for Categories 2G
Group IIC (Zone 1 Group IIC) and 2D Group IIIC (Zone 21 Group IIIC).
• In case of subsequent painting, it must be ensured that the paint used cannot become
electrostatically charged.
• To prevent electrostatic charging, surfaces may only be cleaned with a damp cloth.

1 Safety information
B 2050 en-3023 17
1.3 Applied ignition protection classes according to DIN EN ISO 80079-37
The following ignition protection types are used:
• Measures to ensure constructional safety "c"
– Strength and thermal calculations for all applications,
– Selection of suitable materials and components,
– Calculation of a recommended interval for general overhaul,
– Inspection interval for lubricant level, therefore ensuring lubrication of bearings, seals and gears,
– Requirement for thermal check during commissioning.
• Measures to ensure encapsulation with liquid "k"
– The gears are lubricated with a suitable lubricant,
– Statement of approved lubricants on the name plate,
– Statement of lubricant fill levels.
• Measures to ensure monitoring of sources of ignition "b"
– Use of temperature monitoring for oil cooling systems as ignition protection system b1.
1.4 Do not make any modifications.
Do not make any structural modifications to the gear unit. Do not remove any protective guards. Do not
change the original coating / paint or apply additional coatings / paints.
1.5 Performing inspection and maintenance work
Due to lack of maintenance and damage, malfunctions may occur which can result in personal injury.
• Carry out all servicing and maintenance work at the specified intervals.
• Also note that servicing is necessary after long storage periods prior to commissioning.
• Do not operate damaged gear units. The gear unit must not have any leaks.
1.6 Personnel qualification
All transport, storage, installation, commissioning and maintenance work must be carried out by qualified
specialist personnel.
Qualified specialist personnel are persons who have the training and experience to recognise and avoid
any possible risks.
Repairs may only be done by Getriebebau NORD GmbH & Co. KG or by a person authorised in
accordance with the statutory regulations of explosion protection.
1.7 Safety for particular activities
1.7.1 Check for transport damage
Transport damage may cause malfunctions of the gear unit, which may cause personal injury. Oil which
escapes due to leaks may cause a slipping hazard.
• Check the packaging and the gear unit for transport damage.
• Do not operate damaged gear units.

Explosion-protected industrial gear units – Operating and Assembly Instructions
18 B 2050 en-3023
1.7.2 Safety information for installation and maintenance
Before starting work on the gear unit disconnect the drive from the power supply and secure it against
accidental switch-on. Allow the gear unit to cool down. Depressurise the cooling circuit lines.
Damaged or defective components, attachment adapters, flanges and covers may have sharp edges.
Wear work gloves and work clothing.
1.8 Hazards
1.8.1 Hazards when lifting
Persons may be injured by falling or swinging gear units. Therefore also observe the following
information:
• Cordon off a wide area around the hazard area. Take care that there is adequate space to avoid
swinging loads.
• Never stand under suspended loads.
• Use adequately dimensioned means of transport which are suitable for the purpose. The weight of
the gear unit can be obtained from the type plate.
• Gear units may only be transported with shackles and lifting straps/chains at an angle of 90° to 70°
to the horizontal. Do not use the eye bolts on the motor for lifting if a motor is fitted to the gear unit.
The eye bolts are not designed for lifting the motor with heavy attachments. Pay attention to the
section 3.1 "Transporting the gear unit".
1.8.2 Hazards due to rotating parts
Rotating parts cause a risk of entanglement. This may lead to severe injuries such as crushing or
strangling.
• Provide contact protection. In addition to shafts, this also applies to fans as well as drives and driven
elements such as belt drives, chain drives, shrink discs and couplings. Take possible run-on of the
machine into consideration for the design of protective devices.
• Do not operate the drive without covers or hoods.
• Secure the drive to prevent activation during installation and maintenance work.
• For test operation do not switch on the drive without an installed driven element or secure the motor
shaft key.
• Also observe the safety information in the operating and installation instructions provided by
manufacturers of components supplied.
1.8.3 Danger on entry
Persons may fall and be seriously injured when standing on the gear unit.
• Only stand on the gear unit for maintenance and repair work and only when the gear unit is at a
standstill.
• Never stand on shaft journals, protective covers, attachments and piping.

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B 2050 en-3023 19
1.8.4 Hazards due to high or low temperatures
The gear unit may heat up to 90 °C during operation. Touching hot surfaces or contact with hot oil may
result in burns. At very low ambient temperatures freezing may occur on contact.
• Only touch the gear unit when wearing gloves after operation or at very low ambient temperatures.
• Before starting maintenance work, allow the gear unit to cool down sufficiently after operation.
• Provide a contact guard if there is a risk that persons may touch the gear unit when it is in operation.
• Bursts of hot oil mist may be emitted from the pressure vent screw during operation. Provide a
suitable guard so that persons cannot be injured by this.
• Do not place any flammable materials on the gear unit.
1.8.5 Hazards due to lubricants and other substances
Chemical substances which are used with the gear unit may be toxic. Eye injuries may result if these
substances enter the eyes. Lubricants and adhesives may cause skin irritation.
Oil mist may escape when vent screws are opened.
Due to lubricants and conservation materials, gear units may be slippery and slip out of the hands. There
is a slipping hazard from spilled lubricants.
• When working with chemical substances wear chemical-resistant gloves and work clothing. Wash
your hands after working.
• Wear protective goggles if there is a possibility of splashed chemicals, for example when filling oil or
during cleaning work.
• If chemicals enter the eyes, rinse with large amounts of cold water immediately. Consult a physician
in case of symptoms.
• Observe the safety data sheets for the chemicals. Keep the safety data sheets in the vicinity of the
gear unit.
• Collect spilled lubricants immediately with a binding agent.
1.8.6 Hazards due to noise
Some gear units or attached components may cause hazardous noise levels during operation. Wear
hearing protection if work has to be carried out close to such gear units.
1.8.7 Hazards due to pressurised coolants
The cooling system is under high pressure. Damage or opening a cooling line which is under pressure
may result in injury. Depressurise the cooling circuit before working on the gear unit.

Explosion-protected industrial gear units – Operating and Assembly Instructions
20 B 2050 en-3023
2 Description of gear units
2.1 Gear unit types and type designations
2-stage 3-stage
SK 5207
SK 5307
SK 6207
SK 6307
SK 7207
SK 7307
SK 8207
SK 8307
SK 9207
SK 9307
SK 10207 SK 10307
SK 11207
SK 11307
SK 12207
SK 12307
SK 13207 SK 13307
SK 14207
SK 14307
SK 15207
SK 15307
Table 2: Gear unit overview MAXXDRIVE®Standard – Parallel gear units
3-stage 4-stage
SK 5407
SK 5507
SK 6407
SK 6507
SK 7407
SK 7507
SK 8407
SK 8507
SK 9407
SK 9507
SK 10407
SK 10507
SK 11407 SK 11507
SK 12407
SK 12507
SK 13407
SK 13507
SK 14407 SK 14507
SK 15407
SK 15507
Table 3: Gear unit overview MAXXDRIVE®Standard – Right-angle gear units
2-stage
SK 5217
SK 6217
SK 7217
SK 8217
SK 9217
SK 10217
SK 11217
Table 4: Gear unit overview MAXXDRIVE®XT – Right-angle gear units