SCHUNK ZENTRICO THLS plus User instructions

Steady rest
ZENTRICO THLS plus
Assembly and Operating Manual
Translation of Original Operating
Manual

Imprint
2 06.00 | ZENTRICO THLS plus | Steady rest | en | 0889090
Imprint
Copyright:
This manual is protected by copyright. The author is SCHUNK SE & Co. KG.
All rights reserved.
Technical changes:
We reserve the right to make alterations for the purpose of technical improvement.
Document number: 0889090
Version: 06.00|18/10/2023|en
Dear Customer,
Thank you for trusting our products and our family-owned company, the leading technology
supplier of robots and production machines.
Our team is always available to answer any questions on this product and other solutions. Ask
us questions and challenge us. We will find a solution!
Best regards,
Your SCHUNK team
Customer Management
Tel. [phone]
Fax [phone]
[e-mail]
Please read the operating manual in full and keep it close to the product.

Table of contents
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Table of Contents
1 General ............................................................................................. 5
1.1 About this manual............................................................................... 5
1.1.1 Presentation of Warning Labels ..................................................... 5
1.1.2 Applicable documents ................................................................. 6
1.1.3 Sizes........................................................................................ 6
1.2 Warranty ........................................................................................... 6
1.3 Scope of Delivery................................................................................. 6
2 Basic safety notes ................................................................................ 7
2.1 Intended use...................................................................................... 7
2.2 Not intended use ................................................................................ 7
2.3 Constructional changes......................................................................... 7
2.4 Spare parts ........................................................................................ 8
2.5 Environmental and operating conditions.................................................. 8
2.6 Personnel qualification ........................................................................ 8
2.7 Personal protective equipment .............................................................. 9
2.8 Notes on safe operation........................................................................ 9
2.9 Transport........................................................................................... 10
2.10 Malfunctions ...................................................................................... 10
2.11 Disposal ............................................................................................ 10
2.12 Fundamental dangers .......................................................................... 10
2.12.1 Protection during handling and assembly ....................................... 11
2.12.2 Protection during commissioning and operation ............................... 11
2.12.3 Protection against dangerous movements ....................................... 11
2.12.4 Notes on particular risks .............................................................. 12
3 Technical data ..................................................................................... 15
4 Mounting and connection of the steady rest ............................................... 16
4.1 Torques per screw ............................................................................... 16
4.2 Mounting the steady rest on the steady rest bracket ................................... 16
4.3 Adjustment of the steady rest ................................................................ 17
4.4 Connecting and setting the clamping pressure........................................... 19
4.4.1 Connection dimensions for hydraulics and attachment....................... 21
4.5 Workpiece r.p.m. ................................................................................ 24
4.6 Connection for air purge ....................................................................... 24
4.7 Rinsing connection.............................................................................. 25
4.8 Connection dimensions for central lubrication, air purge and rinsing ............. 26
4.9 Connecting of the path monitoring ......................................................... 27
4.10 APS stroke measuring system ................................................................. 28
4.11 Control of proper function..................................................................... 29
4.12 Commissioning ................................................................................... 29

Table of contents
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5 Troubleshooting................................................................................... 30
6 Maintenance ....................................................................................... 31
6.1 Lubrication ........................................................................................ 31
6.2 Exchange of rollers .............................................................................. 33
6.3 Cleaning the inside of the steady rest ...................................................... 34
7 Assembly drawings ............................................................................... 35
7.1 Basic steady rest ................................................................................. 35
7.2 Cylinder ............................................................................................ 37
8 Part lists ............................................................................................ 39

General
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1 General
1.1 About this manual
This manual contains important information for a safe and
appropriate use of the product.
This manual is an integral part of the product and must be kept
accessible for the personnel at all times.
Before starting work, the personnel must have read and
understood this operating manual. Prerequisite for safe working
is the observance of all safety instructions in this manual.
In addition to these instructions, the documents listed
under }1.1.2 [/6] are applicable.
NOTE: The illustrations in this manual are intended to provide a
basic understanding and may deviate from the actual version.
1.1.1 Presentation of Warning Labels
To make risks clear, the following signal words and symbols are
used for safety notes.
DANGER
Dangers for persons!
Non-observance will inevitably cause irreversible injury or death.
WARNING
Dangers for persons!
Non-observance can lead to irreversible injury and even death.
CAUTION
Dangers for persons!
Non-observance can cause minor injuries.
CAUTION
Material damage!
Information about avoiding material damage.

General
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1.1.2 Applicable documents
lGeneral terms of business *
lCatalog data sheet of the purchased product *
The documents labeled with an asterisk (*) can be downloaded
from schunk.com.
1.1.3 Sizes
This operating manual applies to the following sizes:
lZENTRICO THLS plus 300
lZENTRICO THLS plus 310
lZENTRICO THLS plus 400
lZENTRICO THLS plus 500
lZENTRICO THLS plus 510
lZENTRICO THLS plus 600
1.2 Warranty
If the product is used as intended, the warranty is valid for 24
months from the date of delivery from the production facility or
500 000 cycles* under the following conditions:
lObserve the applicable documents, }1.1.2 [/6]
lObserve the ambient conditions and operating
conditions, }2.5 [/8]
lObserve the specified maintenance and lubrication
intervals, }6 [/31]
Parts touching the workpiece and wear parts are not included in
the warranty.
* A cycle consists of a complete clamping process ("Open" and
"Close").
1.3 Scope of Delivery
1 Steady rest
4 Mounting screws
4 Washers
1 Eye bolt (THLS plus 300 and higher)
1 Operating manual

Basic safety notes
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2 Basic safety notes
2.1 Intended use
This product is intended for clamping workpieces on machine
tools and other suitable technical devices.
lThe product may only be used within the scope of its technical
data, }3 [/15].
lThe product is intended for industrial and industry-oriented
use.
lAppropriate use of the product includes compliance with all
instructions in this manual.
lFor stationary use of the steady rest:
Use cylindrical rollers.
For use of the steady rest axially on a line:
Use spherical rollers.
2.2 Not intended use
A not intended use of the product is for example:
lIt is used as a press, a punch, a toolholder, a load-handling
device or as lifting equipment.
lthe product is used for unintended machines or workpieces.
lthe technical data is exceeded when using the
product. }3 [/15]
lif workpieces are not clamped properly, paying particular
attention to the clamping forces specified by the
manufacturer.
lif it is used in working environments that are not permissible.
lif the product is operated without a protective cover.
2.3 Constructional changes
Implementation of structural changes
Modifications, changes or reworking, e.g.additional threads,
holes, or safety devices, can damage the product or impair its
functionality or safety.
lStructural changes should only be made with the written
approval of SCHUNK.

Basic safety notes
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2.4 Spare parts
Use of unauthorized spare parts
Using unauthorized spare parts can endanger personnel and
damage the product or cause it to malfunction.
lUse only original spare parts or spares authorized by SCHUNK.
2.5 Environmental and operating conditions
Required ambient conditions and operating conditions
Incorrect ambient and operating conditions can make the product
unsafe, leading to the risk of serious injuries, considerable material
damage and/or a significant reduction to the product's life span.
lMake sure that the product is used only in the context of its
defined application parameters, }3 [/15].
l
Make sure that the product is a sufficient size for the application.
lOnly use high-quality cooling emulsions with anti-corrosive
additives during processing.
lLubricating intervals must be adhered to }6.1 [/31].
2.6 Personnel qualification
Inadequate qualifications of the personnel
If the personnel working with the product is not sufficiently qualified,
the result may be serious injuries and significant property damage.
lAll work may only be performed by qualified personnel.
lBefore working with the product, the personnel must have
read and understood the complete assembly and operating
manual.
lObserve the national safety regulations and rules and general
safety instructions.
The following personal qualifications are necessary for the
various activities related to the product:
Trained electrician Due to their technical training, knowledge and experience,
trained electricians are able to work on electrical systems,
recognize and avoid possible dangers and know the relevant
standards and regulations.
Qualified personnel Due to its technical training, knowledge and experience,
qualified personnel is able to perform the delegated tasks,
recognize and avoid possible dangers and knows the relevant
standards and regulations.
Instructed person Instructed persons were instructed by the operator about the
delegated tasks and possible dangers due to improper behaviour.
Service personnel of
the manufacturer
Due to its technical training, knowledge and experience, service
personnel of the manufacturer is able to perform the delegated
tasks and to recognize and avoid possible dangers.

Basic safety notes
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2.7 Personal protective equipment
Use of personal protective equipment
Personal protective equipment serves to protect staff against
danger which may interfere with their health or safety at work.
lWhen working on and with the product, observe the
occupational health and safety regulations and wear the
required personal protective equipment.
lObserve the valid safety and accident prevention regulations.
lWear protective gloves to guard against sharp edges and
corners or rough surfaces.
lWear heat-resistant protective gloves when handling hot
surfaces.
lWear protective gloves and safety goggles when handling
hazardous substances.
lWear close-fitting protective clothing and also wear long hair
in a hairnet when dealing with moving components.
2.8 Notes on safe operation
Incorrect handling of the personnel
Incorrect handling and assembly may impair the product's safety
and cause serious injuries and considerable material damage.
lAvoid any manner of working that may interfere with the
function and operational safety of the product.
lUse the product as intended.
lObserve the safety notes and assembly instructions.
lDo not expose the product to any corrosive media. This does
not apply to products that are designed for special
environments.
lEliminate any malfunction immediately.
lObserve the care and maintenance instructions.
lObserve the current safety, accident prevention and
environmental protection regulations regarding the product's
application field.

Basic safety notes
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2.9 Transport
Handling during transport
Incorrect handling during transport may impair the product's
safety and cause serious injuries and considerable material
damage.
lWhen handling heavy weights, use lifting equipment to lift
the product and transport it by appropriate means.
lSecure the product against falling during transportation and
handling.
lStand clear of suspended loads.
2.10 Malfunctions
Behavior in case of malfunctions
lImmediately remove the product from operation and report
the malfunction to the responsible departments/persons.
l
Order appropriately trained personnel to rectify the malfunction.
lDo not recommission the product until the malfunction has
been rectified.
lTest the product after a malfunction to establish whether it
still functions properly and no increased risks have arisen.
2.11 Disposal
Handling of disposal
The incorrect handling of disposal may impair the product's
safety and cause serious injuries as well as considerable material
and environmental harm.
lFollow local regulations on dispatching product components
for recycling or proper disposal.
2.12 Fundamental dangers
General
lObserve safety distances.
lNever deactivate safety devices.
lBefore commissioning the product, take appropriate
protective measures to secure the danger zone.
lDisconnect power sources before installation, modification,
maintenance, or calibration. Ensure that no residual energy
remains in the system.
l
If the energy supply is connected, do not move any parts by hand.
lDo not reach into the open mechanism or movement area of
the product during operation.

Basic safety notes
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2.12.1 Protection during handling and assembly
Incorrect handling and assembly
Incorrect handling and assembly may impair the product's safety
and cause serious injuries and considerable material damage.
l
Have all work carried out by appropriately qualified personnel.
lFor all work, secure the product against accidental operation.
lObserve the relevant accident prevention rules.
lUse suitable assembly and transport equipment and take
precautions to prevent jamming and crushing.
Incorrect lifting of loads
Falling loads may cause serious injuries and even death.
lStand clear of suspended loads and do not step into their
swiveling range.
lNever move loads without supervision.
lDo not leave suspended loads unattended.
2.12.2 Protection during commissioning and operation
Falling or violently ejected components
Falling and violently ejected components can cause serious
injuries and even death.
l
Take appropriate protective measures to secure the danger zone.
lNever step into the danger zone during operation.
2.12.3 Protection against dangerous movements
Unexpected movements
Residual energy in the system may cause serious injuries while
working with the product.
lSwitch off the energy supply, ensure that no residual energy
remains and secure against inadvertent reactivation.
lNever rely solely on the response of the monitoring function
to avert danger. Until the installed monitors become effective,
it must be assumed that the drive movement is faulty, with its
action being dependent on the control unit and the current
operating condition of the drive. Perform maintenance work,
modifications, and attachments outside the danger zone
defined by the movement range.
lTo avoid accidents and/or material damage, human access to
the movement range of the machine must be restricted. Limit/
prevent accidental access for people in this area due through
technical safety measures. The protective cover and protective
fence must be rigid enough to withstand the maximum
possible movement energy. EMERGENCY STOP switches must be
easily and quickly accessible. Before starting up the machine
or automated system, check that the EMERGENCY STOP system
is working. Prevent operation of the machine if this protective
equipment does not function correctly.

Basic safety notes
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2.12.4 Notes on particular risks
DANGER
Risk of fatal injury from suspended loads!
Falling loads can cause serious injuries and even death.
lStand clear of suspended loads and do not step within their
swiveling range.
lNever move loads without supervision.
lDo not leave suspended loads unattended.
lWear suitable protective equipment.
DANGER
Risk of fatal injury to operating personnel due to the workpiece
falling down or being flung out in the event of a power failure!
In the event of a power failure, the clamping force may fail
immediately and the workpiece may be released in an uncontrolled
manner. This poses a risk of death or injury to the operating
personnel and can result in serious damage to the system.
lThe machine manufacturer and the operator of the machine
must carry out and document a hazard assessment and risk
analysis to ensure that suitable measures are taken to
maintain the clamping force until the machine comes to a
standstill and the workpiece can be secured (e.g. using a
crane or suitable lifting equipment).
l
The steady rest must be pressurized constantly during operation.
lThe standard check valve of the steady rest must not be
disabled or removed.
lThere must be a pressure accumulator in the clamping line of
the steady rest.
l
Take appropriate protective measures to secure the danger zone.
DANGER
Risk of fatal injury to operating personnel due to workpiece
release and flying parts if a lever breaks or if the steady rest
fails because the technical data have been exceeded!
lThe technical data specified by the manufacturer for using
the steady rest must never be exceeded.
lTake appropriate protective measures to secure the danger
zone.

Basic safety notes
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DANGER
Risk of fatal injury to operating personnel due to clothing or
hair being caught on the steady rest and dragged into the
machine!
Loose clothing or long hair may become caught on rotating parts
of the steady rest and be dragged into the machine!
lAlways wear tight-fitting clothing and a hairnet when
working on the machine and the steady rest.
l
Take appropriate protective measures to secure the danger zone.
DANGER
Risk of injury due to the loss of the workpiece and damage to
the steady rest if the maximum RPM and the permissible
maximum circumferential speed of the rollers are exceeded.
lThe technical data and the maximum circumferential speed
of the rollers must never be exceeded.
lA reliable speed limiter must be installed in the machine tool
or technical equipment and proof must be provided that the
speed limiter is effective!
lThe steady rest must not be closed if the workpiece is rotating
at a high speed.
WARNING
There is a risk of injury due to the steady rest falling during
transport, installation or removal.
lTake special care in the danger zone when transporting,
installing or removing the steady rest.
lNote the relevant load securing regulations for working safely
with cranes, ground conveyors, lifting gear and load-
handling equipment.
WARNING
Risk of injury due to high oil pressure if hydraulic lines are not
properly installed.
Hydraulic lines that have not been installed properly can come
loose, causing hydraulic oil to escape at high pressure.
lWear personal protective equipment.
l
Take appropriate protective measures to secure the danger zone.

Basic safety notes
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CAUTION
Risk of slipping or falling if the operational environment is not
clean (e.g. contaminated with cooling lubricants or oil).
lEnsure that the working environment is clean before starting
assembly and installation work.
lWear suitable safety boots.
lFollow the safety and accident prevention regulations when
operating the steady rest, especially when working with
machine tools and other technical equipment.
CAUTION
Risk of limbs being crushed when opening and closing the
levers during manual loading or unloading, or when replacing
moving parts.
lDo not reach in between the levers.
lWear protective gloves.
lFollow the safety and accident prevention regulations when
operating the steady rest, especially when working with
machine tools and other technical equipment.
CAUTION
Risk of burns due to workpieces with high temperatures.
lWear protective gloves when removing the workpieces.
lAutomatic loading is preferred.
CAUTION
Hazard from vibration due to imbalanced rotating parts and
noise generation.
Physical and mental strains due to imbalanced workpieces and
noise during the machining process on the clamped and rotating
workpiece.
lObserve the axial and concentric run-out of the chuck and
the steady rest.
lCheck options for remedying imbalances on special top jaws
and workpieces.
lReduce the speed.
lWear hearing protection.

Technical data
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3 Technical data
THLS plus 300 310 400 500 510 600
ID no. 0825331 0825431 0825531 0825631 0825731 0825831
Piston diameter [mm] 80 80 100 100 100 130
Piston stroke [mm] 77 77 107.8 137.5 137.5 182
Min. operating pressure [bar] 8 8 8 8 8 8
Max. operating pressure [bar] 60 60 60 80 80 70
Max. clamping force / roller [daN] 1000 1000 1500 2000 2000 3000
Centering accuracy [mm]
(overall area)
0.04 0.04 0.05 0.06 0.06 0.06
repeat accuracy [mm] 0.007 0.007 0.01 0.01 0.01 0.02
Max. circumferential speed [m/min] 725 725 715 700 700 700
Clamping range Ø [mm]
(without chip protection)
12 - 152 20 - 165 35 - 245 50 - 310 85 - 350 125 - 460
Clamping range Ø [mm]
(with chip protection)
22 - 152 - - - - -
weight [kg] 59.5 59.5 136 236 236 434
CAUTION
The maximum workpiece speed in relation to the steady rest
depends on the permissible circumferential speed of the steady
rest rollers.
The cutting speed on the clamping diameter is the same as the
circumferential speed of the rollers.
WARNING
Risk of injury due to the loss of the workpiece and damage to
the steady rest if the permissible maximum circumferential
speed of the rollers is exceeded.
lThe technical data and the maximum circumferential speed
of the rollers must never be exceeded.
Pressure loss
In order to ensure that the workpiece remains reliably clamped
for a longer period of time in the case of a sudden drop in
pressure, a pressure accumulator must be fitted in the clamping
line of the steady rest. The following leaks may occur at the
check valve:
THLS plus 300 310 400 500 510 600
Approximate leak at 60 bar [ml/min] 3 3 3 3 3 3
Approximate drop in pressure [bar/min] 40 40 40 40 40 40

Mounting and connection of the steady rest
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4 Mounting and connection of the steady rest
Only perform assembly, conversion, maintenance and adjustment
work when the machine is shut down. It must be ensured that the
steady rest and the machine cannot be operated accidentally by
the installation technician or other persons.
4.1 Torques per screw
Tightening torques for the fastening screws for the steady rest
(screw quality 10.9)
Screw size M6 M8 M10 M12 M14 M16 M18 M20 M22 M24 M27 M30
Admissible torque MA
(Nm)
13 28 50 88 120 160 200 290 400 500 1050 1500
4.2 Mounting the steady rest on the steady rest bracket
The steady rest requires a suitable steady rest bracket in order to
function precisely.
As a fundamental prerequisite, the mounting surface must be flat
and perpendicular to the rotational axis.
The table contains the recommended shape/positional tolerances
for the steady rest bracket's mounting surface.
Steady rest size 300 310 400 500 510 600
Flatness of the mounting surface [mm] 0.03 0.03 0.03 0.05 0.05 0.05
Perpendicularity of the mounting surface to
the rotational axis [mm]
0.03 0.03 0.03 0.05 0.05 0.05
Before assembly, check whether the steady rest bracket is
positioned exactly 90° to the rotational axis.
If required, re-align or rework the steady rest bracket.
Screw the steady rest tightly onto the steady rest bracket using
the four fastening screws and washers supplied. Tighten the
fastening screws to the specified torque }4.1 [/16].
lUse the supplied eye bolt (size 300 and larger) to transport the
steady rest.
WARNING
There is a risk of injury due to the steady rest falling during
transport, installation or removal.
lTake special care in the danger zone when transporting,
installing or removing the steady rest.
lNote the relevant load securing regulations for working safely
with cranes, ground conveyors, lifting gear and load-
handling equipment.

Mounting and connection of the steady rest
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4.3 Adjustment of the steady rest
Alignment of the steady rest
1 Dial gauge 2 Plug gauge
lClamp in a plug gauge between the peaks or in the chuck and
support using a tailstock center. (The plug gauge should be a
short, hardened and toughened ground shaft).
To achieve the repeat accuracy specified in the catalog, the
diameter of the plug gauge must correspond with the
workpiece diameter.
lPlace two dial gauges with 0.01 mm reading and 90° offset on
the plug gauge and check the concentricity at two levels. Set
dial gauges to"0" and keep turned on.
Without fine adjustment to the rollers
lLoosen slightly the four fastening screws on the steady rest, so
that it is gripped with friction.
lClamp the steady rest with the prescribed operation pressure
and tighten the fastening screws slightly. Open the tailstock
center. By reading the dial gauges, ascertain whether the plug
gauge is pressed out of the middle.
If this is the case, correct the steady rest accordingly until the
dial gauges read "0" again.
lTighten the fastening screws. Observe the dial gauges. The
needles must remain on "0".
lOpen the steady rest and clamp again. Check on the dial
gauges whether the plug gauge remains in its position. If the
needles of the dial gauges are displaced, the alignment
procedure must be repeated.

Mounting and connection of the steady rest
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With fine adjustment to the rollers:
lBefore using the fine adjustment of the rollers, the steady rest
must be aligned in the conventional way, see section
"Without fine adjustment to the rollers". Here, the 0 marking
must be aligned in parallel to the bottom edge of the lever.
The fine adjustment is used for readjustment for approaching
clamping pressures and clamping diameters.
Fine adjustment to the rollers
lIn its open position, the steady rest can be twisted beyond
the adjustment range of +/-90° after the screw (pos. 38) is
loosened using a wrench from the eccentric bolts (pos. 10),
after which the screw (pos. 11) is re-tightened. The adjustment
range is:
± 0.10 mm THLS plus 300 to 510
± 0.15 mm THLS plus 600
Eccentric bolt

Mounting and connection of the steady rest
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lAfter adjustment, the concentricity must be checked using a
suitable test shaft. If the desired accuracy is not achieved
using the fine adjustment, the steady rest must be realigned
to the bracket.
CAUTION
If the fastening screws of the steady rest are thightened too
strongly, it may influence the easy moving of the steady rest’s
arms.
l
Check if the levers are easily moving at a lower operating pressure.
l
Tighten the fastening screws with the prescribed tightening torque.
CAUTION
If the operating pressure or the clamping pressure are changed,
the steady rest has to be adjusted again.
4.4 Connecting and setting the clamping pressure
The steady rests are actuated hydraulically by means of an
integrated cylinder or pneumatically as a special version.
NOTE
For pneumatic actuation, the seals and the safety check valve
must be replaced.
The connection lines from the hydraulic or pneumatic unit up to
the self-sealing plug-in couplings are installed as rigid lines,
whereas all the other connection lines must be made of flexible,
metal-sheathed, high-pressure hoses.
NOTE
When using hydraulic pressurization, the steady rest is actuated
using a 4/2-way valve. The pressure valves are integrated into
the clamping line.
When using pneumatic pressurization, the steady rest is actuated
using a 5/2-way valve. The one-way flow control valve is
integrated into the opening line for exhaust air throttling.
There are connections on the back and sides of the steady rest for
the hydraulic lines.
lThe connections that are not used must be sealed off using
the locking screws supplied!

Mounting and connection of the steady rest
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Use hoses and lines with a nominal diameter of 8 mm that are
suitable for an operating pressure of at least 100 bar.
A = clamp - Connection thread sealed with locking screw
B = open - Connection thread sealed with locking screw
Setting the clamping pressure
The clamping pressure on the machine-side pressure control
valve must be set according to the workpiece weight, workpiece
length, machining forces and speed.