Bosch rexroth A4VSH Series User manual

Instruction manual
RE 92110-01-B/2022-03-22, EN
Axial piston
variable pump
A4VSH series 1x and 30

© BoschRexrothAG1989. All rights reserved,
also regarding any disposal, exploitation,
reproduction, editing, distribution, as well
as in the event of applications for industrial
property rights.
The data specified within only serves
todescribe the product. No statements
concerning acertain condition or suitability
for acertain application can be derived from
our information. The information given does
not release the user from the obligation of
own judgment and verification. It must be
remembered that our products are subject to
anatural process of wear and aging.
The cover shows an example application.
The product delivered may differ from the
image on the cover.
The original instruction manual was created
in German.

RE 92110-01-B/2022-03-22, BoschRexrothAG
Contents | A4VSH series 1x and 30 3/64
1 About this documentation ������������������������������������������������������������������������ 5
1.1 Validity of the documentation ...................................................................... 5
1.2 Required and supplementary documentation............................................... 5
1.3 Representation of information...................................................................... 6
1.3.1 Safety instructions ....................................................................................... 6
1.3.2 Symbols ....................................................................................................... 7
1.3.3 Designations ................................................................................................ 7
1.3.4 Abbreviations ............................................................................................... 8
2 Safety instructions ����������������������������������������������������������������������������������� 9
2.1 About this chapter........................................................................................ 9
2.2 Intended use ................................................................................................ 9
2.3 Improper use................................................................................................ 9
2.4 Personnel qualifications ............................................................................. 10
2.5 General safety instructions ........................................................................ 10
2.6 Product-specific safety instructions ........................................................... 12
2.7 Personal protective equipment...................................................................15
3 General instructions on property damage and product damage�������������� 16
4 Scope of delivery������������������������������������������������������������������������������������ 19
5 About this product ��������������������������������������������������������������������������������� 20
5.1 Performance description............................................................................ 20
5.2 Product description ................................................................................... 20
5.2.1 Axial piston unit layout............................................................................... 20
5.2.2 Functional description ............................................................................... 21
5.3 Product identification................................................................................ 22
6 Transport and storage ���������������������������������������������������������������������������� 23
6.1 Transporting the axial piston unit............................................................... 23
6.1.1 Transport by hand ...................................................................................... 23
6.1.2 Transport with lifting devices..................................................................... 24
6.2 Storing the axial piston unit ....................................................................... 25
7 Assembly ����������������������������������������������������������������������������������������������� 27
7.1 Unpacking .................................................................................................. 27
7.2 Installation conditions................................................................................ 27
7.3 Installation position ................................................................................... 29
7.3.1 Below-reservoir installation (standard) ...................................................... 30
7.3.2 Inside-reservoir installation........................................................................ 31
7.3.3 Above-reservoir installation........................................................................ 32
7.4 Installing the axial piston unit.................................................................... 33
7.4.1 Preparation ................................................................................................ 33
7.4.2 Dimensions ................................................................................................ 34
7.4.3 General instructions................................................................................... 34
7.4.4 Installation with acoupling ........................................................................ 35
7.4.5 Installation on agearbox............................................................................ 36
7.4.6 Installation with cardan shaft..................................................................... 36
7.4.7 Completion of assembly............................................................................. 36
7.4.8 Hydraulically connecting the axial piston unit ............................................ 38
7.4.9 Electrically connecting the axial piston unit............................................... 43
7.5 Performing flushing cycle ........................................................................... 44
8 Commissioning��������������������������������������������������������������������������������������� 45
8.1 Initial commissioning ................................................................................. 45
Contents

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BoschRexrothAG, RE 92110-01-B/2022-03-22
8.1.1 Filling the axial piston unit......................................................................... 45
8.1.2 Testing the hydraulic fluid supply............................................................... 47
8.1.3 Performing afunctional test....................................................................... 47
8.2 Running-in phase ....................................................................................... 48
8.3 Recommissioning after standstill ............................................................... 48
9 Operation ����������������������������������������������������������������������������������������������� 49
10 Maintenance and repair�������������������������������������������������������������������������� 50
10.1 Cleaning and care ...................................................................................... 50
10.2 Inspection .................................................................................................. 50
10.3 Maintenance............................................................................................... 51
10.4 Repair ........................................................................................................ 51
10.5 Spare parts ................................................................................................ 52
11 Removal and replacement ���������������������������������������������������������������������� 53
11.1 Required tools............................................................................................ 53
11.2 Preparing for removal................................................................................. 53
11.3 Performing the removal.............................................................................. 53
11.4 Preparing the components for storage or further use................................. 53
12 Disposal ������������������������������������������������������������������������������������������������� 54
13 Extension and conversion����������������������������������������������������������������������� 55
14 Troubleshooting ������������������������������������������������������������������������������������� 56
14.1 How to proceed for troubleshooting........................................................... 56
14.2 Malfunction table ....................................................................................... 57
15 Technical data ���������������������������������������������������������������������������������������� 61
16 Alphabetical index ��������������������������������������������������������������������������������� 62

RE 92110-01-B/2022-03-22, BoschRexrothAG
About this documentation | A4VSH series 1x and 30 5/64
1 About this documentation
1�1 Validity of the documentation
This documentation applies to the following products:
• Axial piston variable pump A4VSH series 1x and 30
This documentation is intended for machine/system manufacturers,
assemblers and service engineers.
This documentation contains important information on the safe and proper
transport, assembly, commissioning, operation, maintenance, removal and simple
troubleshooting of the axial piston unit.
▶ Read this documentation completely, in particular chapter 2
"Safety instructions" on page 9 and chapter 3 "General instructions on
property damage and product damage" on page 16 before you start work
with the axial piston unit.
1�2 Required and supplementary documentation
▶ Only commission the axial piston unit if the documentation marked with the
book symbol is available to you and you have understood and observed it.
Table 1: Required and supplementary documentation
Title Document number Document type
Order confirmation
Contains the technical data relevant to the Axial piston variable pump A4VSH
ordered.
– Order confirmation
Installation drawing
Contains the outer dimensions, all ports and the hydraulic circuit diagram for
your Axial piston variable pump A4VSH.
Please request the
installation drawing
from your contact at
BoschRexroth.
Installation drawing
Axial piston variable pump A4VSH
Contains the permissible technical data, ports, main dimensions and circuit
diagrams of standard versions.
92110 Data sheet
Control devices DR, DP, FR and DFR
Describes the control devices pressure control, pressure control for parallel
operation, flow controller and pressure/flow controller.
92060 Data sheet
Power controller LR2, LR3 and LR2N, LR3N
Describes the power controller with hyperbolic characteristic curve,
which enables mechanical adjustment or hydraulic remote control.
92064 Data sheet
Control systems HM, HS5, HS5E, HS4 and EO
Describes the hydraulic control, volume-related and the control system with
proportional valves.
92076 Data sheet
Hydraulic control, pilot-pressure related HD
Describes the hydraulic control, pilot-pressure-related HD.
92080 Data sheet
Hydraulic fluids based on mineral oils and related hydrocarbons
Describes the requirements for mineral oil-based hydraulic fluids and related
hydrocarbons for operation with Rexroth hydraulic components and provides
support for selection of suitable hydraulic fluids for the hydraulic system.
90220 Data sheet
Environmentally acceptable hydraulic fluids
Describes the requirements for environmentally acceptable hydraulic fluids on
mineral oil basis and related hydrocarbons for operation with Rexroth hydraulic
components, and provides support for selection of suitable hydraulic fluids for
the hydraulic system.
90221 Data sheet

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6/64 A4VSH series 1x and 30 | About this documentation
Table 1: Required and supplementary documentation
Title Document number Document type
Fire-resistant, water-free hydraulic fluids (HFDR/HFDU)
Describes the requirements on fire-resistant, water-free hydraulic fluids
(HFDR/HFDU) for operation with Rexroth hydraulic components and assists you
in selecting ahydraulic fluid for your hydraulic system.
90222 Data sheet
BoschRexroth Fluid Rating List for Rexroth hydraulic components
(pumps and motors)
Contains the hydraulic fluids positively evaluated by BoschRexroth.
90245 Data sheet
Information on the application of hydrostatic drives at low temperatures
Contains additional information on the application of Rexroth axial piston units
at low temperatures.
90300-03-B Manual
Storage and preservation of axial piston units
Contains additional information on storage and preservation.
90312 Data sheet
1�3 Representation of information
Uniform safety instructions, symbols, terms and abbreviations are used throughout
this documentation to ensure safe and proper use of the product. For clarification,
they are explained in the sections below.
1�3�1 Safety instructions
This documentation contains safety instructions in chapter2.6 "Product-specific
safety instructions" on page12 and in chapter3 "General instructions on
property damage and product damage" on page16, as well as before asequence
of actions or an instruction for action involving arisk of personal injury and
property damage. Always follow the measures for danger prevention associated
with the use of this product.
Safety instructions are set out as follows:
SIGNAL WORD
Type and source of danger!
Consequences of non-compliance
▶ Danger prevention measures
•Warning sign: draws attention to the danger
•Signal word: identifies the degree of the danger
•Type and source of danger: indicates the type and source of the danger
•Consequences: describes the consequences of non-compliance
•Precautions: states how the danger can be avoided

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About this documentation | A4VSH series 1x and 30 7/64
Table 2: Hazard classes as defined in ANSI Z535�6
Warning sign, signal word Meaning
DANGER Identifies adangerous situation that will result in death or
serious injury if it is not avoided.
WARNING Identifies adangerous situation that may result in death or
serious injury if it is not avoided.
CAUTION Identifies adangerous situation that may result in minor to
moderate injury if it is not avoided.
NOTICE Property damage: The product or surrounding area may be
damaged.
1�3�2 Symbols
The following symbols indicate notices that are not safety-relevant but increase
understanding of the documentation.
Table 3: Meaning of symbols
Symbol Meaning
If this information is disregarded, the product cannot be used and/or
operated to its full extent.
▶ Single, independent action
1�
2�
3�
Numbered instruction:
The numbers indicate that the actions must be completed in order.
1�3�3 Designations
This documentation uses the following designations:
Table 4: Designations
Designation Meaning
A4VSH Axial piston variable pump in its standard version, semi-closed circuit
Threaded plug Metal screw, pressure-resistant
Protective plug Made out of plastic, not pressure-resistant, only for transportation
As ageneric term for the "axial piston variable motor A4VSH", the designation
"axial piston unit" is used in the following.

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8/64 A4VSH series 1x and 30 | About this documentation
1�3�4 Abbreviations
This documentation uses the following abbreviations:
Table 5: Abbreviations
Abbreviation Meaning
ANSI American National Standards Institute is an organization that coordinates
the development of voluntary standards in the United States
ATEX EC directive on explosion protection (Atmosphère explosible)
DR Pressure control, swiveling on one side
EO Hydraulic control with proportional valve
HD Hydraulic control, pressure-dependent
HM Hydraulic control, volume-related
HS5 Digital, electro-hydraulic control, with control valve
HS5E Digital, electro-hydraulic control, with control valve and OBE
DIN Deutsches Institut für Normung (German Institute for Standardization)
ISO International Organization for Standardization
JIS Japan Industrial Standard
RE Rexroth document in the English language
VDI2230 Guideline for the systematic calculation of heavy-duty
threaded connections and cylindrical screw joints from the
VDI(VereinDeutscherIngenieure - Association of German Engineers)

RE 92110-01-B/2022-03-22, BoschRexrothAG
Safety instructions | A4VSH series 1x and 30 9/64
2 Safety instructions
2�1 About this chapter
The axial piston unit has been manufactured to generally accepted engineering
standards. There is still, however, arisk of personal injury or property damage if
this chapter and the safety instructions in this documentation are not observed.
▶ Read this documentation completely and thoroughly before working with the
axial piston unit.
▶ Keep this documentation in alocation where it is accessible to all users at all
times.
▶ Always include the required documentation when you pass the axial piston unit
on to third parties.
2�2 Intended use
Axial piston units are hydraulic components, meaning that in their application area
they are classified neither as complete nor as partly completed machinery in the
sense of the EC Machinery Directive 2006/42/EC. The component is exclusively
intended to form partly completed machinery or complete machinery together
with other components. The component should only be commissioned after it has
been installed in the machine/system for which it is intended, and the safety of the
entire system has been established in accordance with the Machinery Directive.
This product is intended for the following use:
The axial piston unit is only approved as apump for hydrostatic drives in
semi-closed circuit.
▶ Observe the technical data, the application and operating conditions and
the performance limits as specified in the data sheet 92110 and in the order
confirmation. Information about approved hydraulic fluids can be found in
data sheet 92110.
The axial piston unit is only intended for commercial use and not for private use.
Intended use includes having fully read and understood this documentation,
especially chapter 2 "Safety instructions" on page 9.
2�3 Improper use
Any use other than that described as intended use is considered improper.
BoschRexrothAG is not liable for damage resulting from improper use.
The user is solely responsible for any risks arising from improper use.
The following foreseeable forms of faulty usage are also considered improper
(this list is not exhaustive):
• Use outside the operating parameters approved in the data sheet and in the order
confirmation (unless specifically approved by the customer)
• Use of non-approved fluids, e.g.water or polyurethane components
• Changes to factory settings by unauthorized persons
• Use of assembled parts (e.g.attachment filter, control unit, valves) other than
specified Rexroth components
• Use of the axial piston unit with assembled parts under water at adepth
of more than 10 meters without the necessary additional measures,
e.g.pressure equalization. Units with electrical components (e.g.sensors)
must not get into contact with water, depending on the IP protection class.
Observe the IP protection class in the data sheet 92110.

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10/64 A4VSH series 1x and 30 | Safety instructions
• Use of the axial piston unit under acontinuous pressure differential between
housing and ambient pressure greater than 2bar, with the ambient pressure
always lower than the case pressure. Momentary (t<0.1s) pressure peaks of
up to 6bar are allowed. Beyond this, the maximum permissible case pressure
specified in the data sheet should not be exceeded.
• Application of the axial piston unit in explosive environments unless the
component or machine/system has been certified as compliant with the
ATEX Directive 2014/34/EU
• Use of the axial piston unit in acorrosive atmosphere
• Use of the axial piston unit in aircraft or spacecraft
2�4 Personnel qualifications
The activities described in this documentation require abasic understanding
of mechanics, electricity and hydraulics, as well as familiarity with associated
technical terms. For transporting and handling the product, knowledge regarding
the use of lifting devices and lifting accessories is required. In order to ensure
safe use, these activities should only be performed by skilled personnel or an
instructed person under the direction and supervision of skilled personnel.
Skilled personnel refers to persons who possess the professional training,
knowledge and experience, as well as the understanding of the regulations
relevant to the work to be done that are necessary to recognize possible dangers
and take the appropriate safety measures. Skilled personnel must follow the rules
relevant to their field and have the necessary hydraulic expert knowledge.
Hydraulic expert knowledge includes:
• Being able to read and fully understand hydraulic circuit diagrams
• In particular, fully understanding the relationships with regard to safety devices
• Knowledge regarding the function and interaction of hydraulic components.
BoschRexroth offers you measures supporting training in specific areas.
You can find an overview of the training contents on the Internet at:
www.boschrexroth.com/training.
2�5 General safety instructions
• Observe the country-specific accident prevention and environmental protection
regulations.
• Observe the safety regulations of the country in which the product is
used/operated.
• Use Rexroth products only when they are in good working order.
• Observe all notices on the product.
• Do not assemble, operate, remove or maintain Rexroth products if under the
influence of alcohol, drugs or medication that may affect your reaction time.
• Only use genuine Rexroth accessories and spare parts to ensure there is no
hazard to persons from unsuitable spare parts.
• Observe the technical data and ambient conditions specified in the product
documentation.
• If unsuitable products are installed or used in safety-relevant applications,
unexpected operating conditions may occur in the application, which could result
in personal injury or property damage. For this reason, only use the product in
safety-relevant applications if this use is expressly indicated and approved in the
product documentation, e.g.in explosion protection areas or in safety-related
parts of acontrol system (functional safety).

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Safety instructions | A4VSH series 1x and 30 11/64
• Only commission the product if it has been determined that the end product
(e.g.machinery/system) in which the Rexroth products are installed complies
with the country-specific provisions, safety regulations and standards for the
application.
• Use tools appropriate for the work being performed and wear appropriate
protective clothing to prevent punctures and cuts (e.g.when removing protective
covers, disassembly).
• There is arisk of entanglement when operating the axial piston unit with
abare shaft end. Check whether or not your machine requires additional safety
measures for your application. If necessary, make sure these are appropriately
implemented.
• Depending on the type of control used, electromagnetic effects can be produced
when using solenoids. Applying adirect voltage signal (DC) to solenoids does not
create electromagnetic interference (EMI) nor is the solenoid affected by EMI.
Potential electromagnetic interference (EMI) exists if the solenoid is energized
with amodulated direct current (e.g.PWM signal). The machine manufacturer
should conduct appropriate tests and take appropriate measures to ensure that
other components or operators (e.g.with apacemaker) are not affected by this
potentiality.

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12/64 A4VSH series 1x and 30 | Safety instructions
2�6 Product-specific safety instructions
The following safety instructions apply for chapters 6 to 14.
WARNING
Danger from excessive pressure!
Risk of death or injury, or property damage!
Improperly changing the factory pressure settings can result in apressure
increase beyond the permissible maximum pressure.
Operating the unit above the maximum permissible pressure can cause
components to burst and hydraulic fluid to escape under high pressure.
▶ Changes to the factory settings may only be made by BoschRexroth
specialists.
▶ In addition, apressure relief valve is required in the hydraulic system as
back-up. If the axial piston unit is equipped with apressure cut-off and/
or pressure controller, this is not an adequate safeguard against pressure
overload.
Danger due to suspended loads!
Risk of death or injury, or property damage!
Improper transportation may cause the axial piston unit to fall down and lead to
injury, e.g.crushing or fracture, or damage to the product.
▶ Make sure that the load bearing capacity of the lifting device is sufficient to
safely bear the weight of the axial piston unit.
▶ Never step or grip under suspended loads.
▶ Ensure astabletransport position.
▶ Use your personal protective equipment (e.g.safety goggles, safety gloves,
suitableworking clothes, safety shoes).
▶ Use suitablelifting devices for transport.
▶ Observe the prescribed position of the lifting strap.
▶ Observe the national laws and regulations on occupational health and safety,
and transportation.
System/machine under pressure!
Risk of death or serious injury when working on unsecured machines/systems!
Property damage!
▶ Switch off the relevant machine/system part and secure it against reactivation
according to the parameters by the machine/system manufacturer.
▶ Ensure that all relevant components of the hydraulic system are depressurized.
For this purpose, observe the parameters indicated by the machine/system
manufacturer.
▶ Please note that the hydraulic system might still be pressurized even after
separation from the actual pressure supply.
▶ Do not disconnect any line connections, ports or components as long as the
hydraulic system is under pressure.

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WARNING
Escaping hydraulic fluid mist!
Risk of explosion and fire hazard, health hazard, risk of environmental pollution!
▶ Depressurize the relevant machine/system component and repair the leak.
▶ Only perform welding work when the machine/system is depressurized.
▶ Keep open flames and ignition sources away from the axial piston unit.
▶ If axial piston units are located in the vicinity of ignition sources or powerful
thermal radiators, ashield must be erected to ensure any escaping hydraulic
fluid cannot be ignited, and to protect hose lines from premature aging.
Escaping hydraulic fluid due to leakage of machine/system components!
Risk of burning and risk of injury due to escaping hydraulic fluid jet!
In case of leakage at the axial piston unit, high-pressure
fluid jets may escape.
▶ Depressurize the relevant machine/system component and repair the leak.
▶ Never attempt to block or seal the leak or hydraulic fluid jet with acloth.
Hydraulic fluid will explode when making contact with water!
Explosion and fire hazard!
▶ Do not bring hot hydraulic fluids in contact with water.
Electrical voltage!
Danger to life or risk of injury due to electric shock or property damage!
▶ Always disconnect the voltage supply to the relevant machine/system
part before installing the product and/or connecting or disconnecting the
connector. Protect the machine/system against being re-energized.
Restriction of control function!
Risk of injury or property damage!
Under certain circumstances, moving parts in control equipment (e.g., valve spools)
can get stuck in an undefined position due to contamination (e.g., impure hydraulic
fluid, abrasion or residual dirt from components). As aresult, the hydraulic fluid
flow and the build-up of torque in the axial piston unit can no longer respond
correctly to the operator’s specifications. Even the use of various filter elements
(external or internal flow filtration) will not rule out afault but merely reduce
the risk.
▶ Check whether your application requires remedial measures on your machine
in order to bring the driven consumer to asafe position (e.g.safe stop).
▶ If necessary, make sure these are properly implemented.

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14/64 A4VSH series 1x and 30 | Safety instructions
CAUTION
High noise development during operation!
Risk of hearing damage or hearing loss!
The noise emission of axial piston units depends on rotational speed,
working pressure and installation conditions, among other factors.
The sound pressure level may rise above 70 dB (A) in certain application
conditions.
▶ Always wear hearing protection near arunning axial piston unit.
High noise development due to non-closing anti-cavitation valves!
Danger of hearing damage, property damage!
Non-closing anti-cavitation valves, e.g.due to contamination of the hydraulic fluid,
can lead to increased noise development and pressure increase in the suction
line.
▶ Check the contamination of the hydraulic fluid, change the pressure fluid
if necessary and have the anti-cavitation valves checked or replaced by the
BoschRexrothService.
▶ Lines for ports SAand SBmay only be pressurized with the maximum
permissible suction pressure of 16 bar and must discharge into the tank
below the minimum operating fluid level.
Hot surfaces on axial piston unit!
Risk of getting burnt!
▶ Allow the axial piston unit to cool down sufficiently before touching it.
▶ Wear heat-resistant, protective clothing, e.g.gloves.
Improper cable and line routing!
Risk of stumbling and property damage! Improper routing of cables and lines
can cause arisk of stumbling as well as damage to equipment and components,
e.g.due to lines and connectors being torn off.
▶ Always lay cables and lines so no one can trip over them, they do not become
kinked or twisted, do not rub on edges and do not run through sharp-edged
ducts without adequate protection.
Contact with hydraulic fluid!
Risk of adverse health effects, e.g.eye injury, skin irritation, toxication from
inhalation!
▶ Avoid any contact with hydraulic fluids.
▶ When handling hydraulic fluids, the safety instructions of the lubricant
manufacturer need to be observed at all times.
▶ Use your personal protective equipment (e.g.safety goggles, safety gloves,
suitableworking clothes, safety shoes).
▶ Immediately seek medical attention, however, if hydraulic fluid gets into your
eyes or blood circuit or if you swallow it accidentally.
Danger from improper handling!
Slip hazard! Risk of slipping on wet surfaces when climbing on the axial piston unit.
▶ Never grab or climb onto the axial piston unit.
▶ Check how to safely get on top of the machine/system.

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2�7 Personal protective equipment
Personal protective equipment is the responsibility of the user of the axial piston
unit. Observe the safety regulations in your country.
All pieces of personal protective equipment must be intact.

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16/64 A4VSH series 1x and 30 | General instructions on property damage and product damage
3 General instructions on property
damage and product damage
The following information applies to chapters 6 to 14.
NOTICE
Danger from improper handling!
Product can be damaged!
▶ Do not subject the product to improper mechanical loads.
▶ Never use the product as handle or step.
▶ Do not put/place any objects on the product.
▶ Do not strike the drive shaft of the axial piston unit.
▶ Do not set/place the axial piston unit on the drive shaft or assembled parts.
▶ Do not strike assembled parts (e.g.sensors. solenoids or valves).
▶ Do not hit sealing surfaces (e.g.on the work connections).
▶ Leave the protective covers on the axial piston unit until you connect the lines.
▶ Disconnect all electrical connectors before arc welding and painting operations.
▶ Make sure the electronic components (e.g.sensors) do not build up
electrostatic charges (e.g.during painting).
Risk of property damage due to inadequate lubrication!
Product can be damaged or destroyed!
▶ Never operate the axial piston unit with insufficient hydraulic fluid.
Specifically, make sure that the rotary group has sufficient lubrication.
▶ When commissioning amachine/system, make sure that the housing area and
the working lines of the axial piston unit are filled with hydraulic fluid and
remain filled during operation. Avoid air inclusions in the forward drive shaft
bearing, especially with the axial piston unit installed with the drive shaft
upward.
▶ Check the hydraulic fluid level in the housing area regularly and replenish,
if necessary. For above-reservoir installation, the housing area may drain out
through the drain line after prolonged standstill periods (air enters through
the shaft seal) or through the working line (gap leakage). This means the
bearings are insufficiently lubricated when the system is turned on.
▶ Make sure the boost line and suction line to the anti-cavitation valves are
always filled with hydraulic fluid during commissioning and operation.
▶ Ensure in case of above-reservoir installation that before initial start-up of the
axial piston pump (commissioning or recommissioning), the suction line to
the anti-cavitation valves is completely filled with hydraulic fluid. Make certain
that the axial piston pump does suck in hydraulic fluid and build up pressure
directly after start-up. In case of longer standstill period, suitable measures
have to be taken to prevent draining of the suction lines.

RE 92110-01-B/2022-03-22, BoschRexrothAG
General instructions on property damage and product damage | A4VSH series 1x and 30 17/64
NOTICE
Mixing hydraulic fluids!
Product can be damaged!
▶ Before installation, remove all fluids from the axial piston unit to prevent
mixing with the hydraulic fluid used in the machine/system.
▶ Any mixture of hydraulic fluids of different manufacturers and/or different
types of the same manufacturer is generally not permissible.
Contamination of hydraulic fluid!
The cleanliness of the hydraulic fluid impacts the service life of the axial piston
unit. Contamination of the hydraulic fluid may lead to premature wear and
malfunctions!
▶ Always ensure awork environment in the assembly location that is free from
dust and foreign particles to prevent foreign particles, e.g.welding beads
or metal cuttings, from entering the hydraulic lines and lead to wear and
malfunctions in the product. The axial piston unit should be clean when
installed.
▶ Only use clean ports, hydraulic lines and assembled parts
(e.g.measuring devices).
▶ When plugging the ports, no contamination must ingress.
▶ Before commissioning, ensure that all hydraulic connections are tight and
that all seals and plugs of the plug-in connection are correctly installed and
undamaged to prevent fluids and foreign particles from entering the product.
▶ Filter the hydraulic fluid when filling the system with asuitablefilter system
to minimize the solid particle contamination and water in the hydraulic system
and to achieve the required cleanliness level.
Improper cleaning!
Product can be damaged!
▶ Plug all openings with appropriate protective covers in order to prevent
cleaning agents from entering the axial piston unit.
▶ Never use solvents or aggressive cleaning agents. Use only water and,
if necessary, amild cleaning agent to clean the axial piston unit.
▶ Do not point ahigh-pressure cleaner at sensitive components, e.g.shaft seal,
electrical connections and components.
▶ Use fiber-free cleaning cloth.
Environmental pollution due to improper disposal!
Careless disposal of the axial piston unit and its assembled parts, the hydraulic
fluid and the packaging material can cause environmental pollution!
▶ Dispose of the axial piston unit, hydraulic fluid and packaging in accordance
with the regulations in your country.
▶ Dispose of the hydraulic fluid in accordance with the applicable safety
data sheet for the hydraulic fluid.

BoschRexrothAG, RE 92110-01-B/2022-03-22
18/64 A4VSH series 1x and 30 | General instructions on property damage and product damage
NOTICE
Danger from chemical or corrosive environmental conditions!
Product can be damaged! If the axial piston unit is exposed to chemical or
corrosive environmental conditions, such as sea water, fertilizer or road salt,
it can result in corrosion or, in extreme cases, malfunction. Leaks may lead to
leakage of hydraulic fluid.
▶ Take appropriate measures to protect the axial piston unit from chemical or
corrosive environmental conditions.
Leakage or spilling of hydraulic fluid!
Risk of environmental pollution and contamination of ground water!
▶ Always place adrip tray under the axial piston unit when filling and draining
hydraulic fluid.
▶ Use asuitable binding agent to collect any leaked hydraulic fluid.
▶ Observe the parameters in the safety data sheet for the hydraulic fluid and the
specifications provided by the machine/system manufacturer.
Danger from hot components!
Nearby products can be damaged! Components which heat up (e.g.,solenoids)
can cause damage to nearby products if they are too close during installation.
▶ When installing the axial piston unit, check the safety distances to nearby
products to ensure that they are not damaged.
The warranty only applies to the machine configuration as delivered.
The warranty will be voided if the product is incorrectly installed, commissioned or
operated, or if it is used or handled improperly.

RE 92110-01-B/2022-03-22, BoschRexrothAG
Scope of delivery | A4VSH series 1x and 30 19/64
4 Scope of delivery
1
1
1
2
3
21
Fig� 1: Axial piston unit
Included in the scope of delivery:
• Axial piston unit as per order confirmation
The following parts come assembled on the unit:
• Protective covers (1)
• Protective plug/threaded plugs(2)
• Protective cover for through drive (3)

BoschRexrothAG, RE 92110-01-B/2022-03-22
20/64 A4VSH series 1x and 30 | About this product
5 About this product
5�1 Performance description
The axial piston variable pump generates, controls and regulates ahydraulic fluid
flow.It is designed for stationary applications.
Refer to data sheet 92110 and the order confirmation for the technical data,
operating conditions and application limits of the axial piston unit.
5�2 Product description
A4VSH is avariable pump with an axial piston rotary group in swashplate design
for hydrostatic drives in semi-closed circuits. Flow is proportional to drive speed
and displacement. The flow can be changed steplessly by controlling the
swashplate (cradle) (11). For axial piston units with swashplate design,
the pistons(9) are arranged axially relative to the drive shaft.
In the semi-closed circuit, the hydraulic fluid flows from the hydraulic pump to the
consumer, then directly back to the hydraulic pump. There is then ahigh-pressure
side (5) and alow-pressure side(6), which can change according to loading.
Missing hydraulic fluid and related cavitation in the respective low-pressure side is
compensated for by anti-cavitation valves.
5�2�1 Axial piston unit layout
10
3
7
5
8
4
2
6
9
11
1
Fig� 2: A4VSH layout
1 Drive shaft
2 Retaining plate
3 Stroking piston
4 Control plate
(Distributor plate)
5 Pressure side Bwith
anti-cavitation valve
6 Pressure side Awith
anti-cavitation valve
7 Port plate
8 Cylinder
9 Piston
10 Slipper pad
11 Swashplate
(Cradle)
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Semi-closed circuit