SCHUNK ROTA THWplus User instructions

Power chuck
ROTA THWplus
Assembly and operating manual
Translation of original operating
manual

Imprint
2 04.00 | ROTA THWplus | Power chuck | en | 0889021
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: 0889021
Version: 04.00|18/07/2023|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 Warnings........................................................................................... 5
1.2 Applicable documents .......................................................................... 6
2 Basic safety instructions......................................................................... 7
2.1 Intended use...................................................................................... 7
2.2 Not intended use ................................................................................ 7
2.3 Notes on particular risks ....................................................................... 8
2.4 Notes on safe operation........................................................................ 11
2.4.1 Substantial modifications ............................................................ 14
2.5 Personnel qualification ........................................................................ 14
2.6 Organizational measures....................................................................... 14
2.7 Using personal protective equipment ...................................................... 15
3 Warranty............................................................................................ 16
4 Torques per screw ................................................................................ 17
5 Scope of delivery .................................................................................. 18
6 Technical data ..................................................................................... 19
6.1 Chuck data ........................................................................................ 19
6.2 Clamping force / speed diagrams ............................................................ 19
6.3 Calculations for clamping force and speed ................................................ 22
6.3.1 Calculation of the required clamping force in case of a given rpm......... 22
6.3.2 Calculation example: required initial clamping force for a given speed .. 24
6.3.3 Calculation of the permissible speed in case of a given initial clamping
force ....................................................................................... 25
6.4 Grades of Accuracy .............................................................................. 26
6.5 Permissible imbalance ......................................................................... 26
7 Attachment and disassembly of the chuck .................................................. 27
7.1 Pre-assembly measures........................................................................ 27
7.2 Mounting of the Chuck to the Machine Spindle .......................................... 27
7.3 Disassembling and assembling the chuck ................................................. 32
8 Function and handling .......................................................................... 34
8.1 Function of the chuck .......................................................................... 34
8.2 Handling the chuck and the base jaws..................................................... 34
8.3 Base jaw position................................................................................ 35
8.4 Change or supplement of jaws ............................................................... 36
9 Maintenance ....................................................................................... 37
9.1 Lubrication ........................................................................................ 37

Table of contents
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9.2 Maintenance intervals.......................................................................... 38
9.3 Technical condition ............................................................................. 38
10 Disposal ............................................................................................. 39
11 Chuck mounts and Spare parts................................................................. 40
11.1 Chuck mounts .................................................................................... 40
11.2 Spare parts ........................................................................................ 40
12 Drawings ........................................................................................... 42

General
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1 General
This operating manual is an integral component of the product
and contains important information on safe and proper
assembly, commissioning, operation, care, maintenance and
disposal. This manual must be stored in the immediate vicinity of
the product where it is accessible to all users at all times.
Before using the product, read and comply with this manual,
especially the chapter “Basic safety notes”.}2 [/7]
If the product is passed on to a third party, these instructions
must also be passed on.
Illustrations in this manual are provided for basic understanding
of the product and may differ from the actual product design.
We accept no liability for damage resulting from the failure to
observe and comply with this operating manual.
1.1 Warnings
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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WARNING
Warning about hand injuries
WARNING
Warning about hot surfaces
1.2 Applicable documents
lGeneral terms of business *
lCatalog data sheet of the purchased product *
lCalculation of the jaw centrifugal forces, "Technology" chapter
in the lathe chuck catalog *
The documents labeled with an asterisk (*) can be downloaded
from schunk.com.

Basic safety instructions
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2 Basic safety instructions
Improper handling, assembly and maintenance of this product
may result in risks to persons and equipment if this operating
manual is not observed.
Report any failures and damage immediately and repair without
delay to keep the extent of the damage to a minimum and
prevent compromising the safety of the product.
Only original SCHUNK spare parts may be used.
NOTE
We hereby confirm that the components comply with the
relevant basic and proven safety principles of Annex A and C of
ISO 13849-2, taking into account the requirements of the
documentation. The parameters, limitations, ambient conditions,
characteristic values, etc. for proper operation are defined in the
operating manual.
2.1 Intended use
The product is suitable for clamping workpieces on milling or
lathe machines and other suitable tooling machines.
The product is intended for industrial use.
Intended use also means that the user has read and understood
this operating manual in its entirety, especially the chapter
“Basic safety notes”.
lThe maximum RPM of the chuck and the required clamping
force must be determined by the user for the respective
clamping task based on the applicable standards and
technical specifications of the manufacturer.
(See also “Calculations for clamping force and RPM” in the
chapter “Technical data”). }6 [/19]
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. }6 [/19]
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.

Basic safety instructions
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2.3 Notes on particular risks
This product may pose a danger to persons and property if, for
example:
lIt is not used as intended;
lIt is not installed or maintained properly;
lThe safety and installation instructions, local applicable safety
and accident prevention regulations or the EC Machinery
Directive are not observed.
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 lathe chuck's 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
automated 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 lathe chuck's clamping force until the machine
comes to a standstill and the workpiece can be secured (e.g.
using a crane or suitable lifting equipment).
lThe machines and equipment must fulfill the minimum
requirements of the EC Machinery Directive; specifically, they
must have effective technical measures to protect against
potential mechanical hazards.
DANGER
Possible risk of fatal injury to operating personnel if a jaw
breaks or if the lathe chuck fails because the technical data
have been exceeded and a workpiece is released or parts fly off
lThe technical data specified by the manufacturer for using
the lathe chuck must never be exceeded.
lThe lathe chuck may only be used on machines and facilities
that fulfill the minimum requirements of the EC Machinery
Directive; specifically, they must have effective technical
measures to protect against possible mechanical hazards.

Basic safety instructions
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DANGER
Possible risk of fatal injury to operating personnel from
clothing or hair being caught on the lathe chuck and being
dragged into the machine
Loose clothing or long hair may become caught on projecting
parts of the lathe chuck and be drawn into the machine.
lThe machines and equipment must fulfill the minimum
requirements of the EC Machinery Directive; specifically, they
must have effective technical measures to protect against
potential mechanical hazards.
lAlways wear tight-fitting clothing and a hairnet when
working on the machine and the lathe chuck.
WARNING
Risk of injury due to dropping the chuck during transport,
installation or removal.
lTake special care in the danger zone when transporting,
installing or removing the chuck.
lNote the relevant load securing regulations for working safely
with cranes, ground conveyors, lifting gear and load-
handling equipment.
CAUTION
Danger of slipping and falling in case of dirty environment
where the chuck is used (e.g. by cooling lubricants or oil).
lEnsure that the working environment is clean before starting
assembly and installation work.
lWear suitable safety shoes.
lFollow the safety and accident-prevention regulations when
operating the chuck, especially when working with machine
tools and other technical equipment.

Basic safety instructions
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CAUTION
Danger of limbs being crushed by opening and closing of the
chuck jaws during manual loading and unloading or when
replacing moving parts.
lDo not reach between the jaws.
lWear safety gloves.
lObserve the safety and accident prevention regulations
during operation of the chuck, especially in connection with
machining centers 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
Danger of damage due to incorrectly selected clamping position
of the clamping jaws to the workpiece.
An incorrectly selected clamping position of the clamping jaws to
the workpiece can result in damage to the base and top jaws.
lMake sure that the workpiece clamping is concentric.
lIn the case of a chuck with a quick-change jaw system the
top jaws must not protrude radially beyond the base jaws
used.
Exception: The supporting jaw variant 3 protrudes beyond the
chuck base jaw due to the construction of the jaw. In this
case, the T-nuts must always be inserted completely into the
groove of the chuck base jaw.

Basic safety instructions
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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.
lEnsure the chuck's axial and concentric runout.
lCheck options for remedying imbalances on special top jaws
and workpieces.
lReduce the speed.
lWear hearing protection.
2.4 Notes on safe operation
lThe machine spindle may only be started up when clamping
pressure has built up in the cylinder and clamping has
followed in the permitted work area.
lUnclamping may only be possible when the machine spindle
has come to a standstill.
lIf the clamping energy fails, the workpiece must remain firmly
clamped until the spindle is shut down and the workpiece is
secured.
lThe technical safety requirements in the respective operating
instructions must be observed exactly.
Functional test
After installation of the chuck, its function must be checked prior
to start-up.
Two important points are:
lClamping Force! The clamping force of the chuck must be
achieved at max. operating force/pressure.
lStroke control! The stroke of the clamping piston must allow a
safety zone at the front and rear end position. The machine
spindle may only be started when the clamping piston has
passed through the safety zone. Only limit switches that meet
the requirements for safety limit switches specified in DIN EN
60204-1 may be used.
When determining the necessary clamping force to machine a
workpiece, take the centrifugal force acting on the chuck jaws
into account (according to VDI 3106).
If the chuck jaws are changed, adjust the stroke control to the
new situation.

Basic safety instructions
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Speed of rotation
DANGER
Possible risk of fatal injury to operating personnel if the
chuck's top speed is exceeded and a workpiece is released or
parts fly off.
If the machine tool or technical equipment can reach a higher
speed than the chuck's top speed, a reliable speed limiter must
be installed and proof must be provided that the speed limiter is
effective.
Maintenance instructions
The chuck's reliability and safety can only be guaranteed if the
operator complies with the manufacturer's maintenance
instructions.
lFor lubrication, we recommend our tried and tested special
grease, LINOMAX plus. Unsuitable lubricants can have a
negative impact on the functioning of the chuck (clamping
force, coefficient of friction, wear characteristics).
(For product information about LINOMAX plus, see the
"Accessories" chapter of the SCHUNK lathe chuck catalog or
contact SCHUNK.)
lUse a suitable high-pressure grease gun to ensure that you
reach all the greasing areas.
lTo ensure correct distribution of the grease, move the
clamping piston to its end positions several times, lubricate
again, and then check the clamping force.
lWe recommend checking the clamping force using a clamping
force tester before starting a new production run and
between maintenance intervals. *Optimum safety can only be
guaranteed through regular checks*.
lThe clamping force should always be measured in the state of
the lathe chuck as used for the current clamping situation. If
top jaws with clamping steps are used, measuring must be
performed in the same step as for the respective clamping
task. In the event of high operating speeds, clamping force
losses must be accounted for due to the centrifugal force
acting on the chuck jaws. In this case the value of the
operating clamping force should be measured dynamically.
lMove the clamping piston through to its end position several
times after 500 clamping strokes, at the latest (This moves the
lubricant back to the surfaces of the force transmission, so
that the clamping force is retained for longer).

Basic safety instructions
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Safety notes for servicing
Follow all the applicable legal standards for health and safety
during servicing. Use suitable personal protective equipment,
especially protective gloves, goggles, and safety boots - paying
particular attention to the operating system and hazard
assessment.
DANGER
Possible risk of fatal injury to operating personnel due to
toolholder failure if the maintenance and servicing instructions
for the toolholder are disregarded.
The servicing instructions specified by the manufacturer must be
complied with to ensure safe operation of the chuck.
Work must be carried out by qualified specialist personnel with
the relevant safety training.
Observe the maintenance instructions in this manual.
Use of special chuck jaws
When using special chuck jaws, please observe the following
rules:
lThe chuck jaws should be designed to be as light and as low
as possible. The clamping point must be as close as possible
to the chuck face (clamping points at a greater distance lead
to greater surface pressure in the jaw guidance and can
significantly reduce the clamping force).
lDo not use welded jaws.
lIf for constructional reasons the chuck jaws in special design
are heavier than the top jaws assigned to the clamping
device, greater centrifugal forces must be accounted for when
defining the required clamping force and the recommended
speed.
lScrew the jaw mounting screws into the bore holes furthest
apart.
lThe maximum recommended speed may only be operated in
conjunction with maximum actuating force and only with the
chuck in optimal, fully functioning condition.
lIf the chuck is involved in a collision, it must be subjected to
a crack test before using it again. Replace damaged parts with
original SCHUNK spare parts.
lReplace the chuck jaw mounting screws if there are signs of
wear or damage. Only use screws with a quality of 12.9.

Basic safety instructions
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2.4.1 Substantial modifications
No substantial modifications may be made to the chuck.
If the operator carries out a substantial modification to the
chuck, the product shall no longer conform to the EC Machinery
Directive 2006/42/EC.
2.5 Personnel qualification
Assembly and disassembly, commissioning, operation and repair
of the chuck may be performed only by qualified specialists who
have been instructed with respect to safety.
All persons who are assigned to operate, maintain and repair our
chuck must have access to the operating manual, especially the
chapter “Fundamental safety instructions”. We recommend that
the operator create in-house safety operating instructions.
Persons in training may be assigned to machines and technical
equipment in which a chuck is mounted only if they are under
the constant guidance and supervision of qualified specialists.
2.6 Organizational measures
Obeying the rules
By means of suitable organizational measures and instructions,
the operator must ensure that the relevant safety rules are
obeyed by any persons asked to operate, maintain and repair the
lathe chuck.
Monitoring the behavior of personnel
The operator must check that the personnel are behaving in a
safety-conscious manner and are aware of the potential hazards
at least from time to time.
Danger signs
The operator must ensure that the signs concerning safety and
hazards on the machine where the lathe chuck is mounted are
clearly legible and observed.
Faults
If a fault occurs on the lathe chuck and this fault endangers
safety or if a problem is suspected due to production
characteristics, the machine tool where the lathe chuck is
mounted must be immediately stopped and remain shut down
until the fault has been located and remedied. Only allow
specialists to remedy malfunctions.
Spare parts
Only ever use original SCHUNK spare parts.
Environmental regulations
Comply with the applicable legal norms when disposing of waste.

Basic safety instructions
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2.7 Using personal protective equipment
When using this product, you must comply with the relevant
health and safety at work rules and you must use the required
personal safety equipment (minimum: category 2).

Warranty
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3 Warranty
If the product is used as intended, the warranty is valid for 24
months from the ex-works delivery date under the following
conditions:
lObserve the applicable documents, }1.2 [/6]
lObserve the ambient conditions and operating conditions
lObserve the maximum number of clamping cycles }6 [/19]
lObserve the specified maintenance and lubrication
intervals, }9 [/37]
Parts touching the workpiece and wear parts are not included in
the warranty.

Torques per screw
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4 Torques per screw
Tightening torques for mounting screws used to clamp the
chuck on lathes or other suitable technical equipment (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
Tightening torques for mounting screws used to attach top
jaws onto the chuck (screw quality 12.9)
Screws for base jaws
GB / GBK / GBK-V / GBKL
M6 M8 M10 M12 - M16 M20 - M24
perm. tightening torque in Nm 16 25 60 80 - 100 180 - 230

Scope of delivery
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5 Scope of delivery
ROTA THW plus 165, 185, 215:
1 Power chuck
1Set of base jaws
3 Mounting screws
1 Jaw change key
1 Operating manual
1 Short operating manual
ROTA THW plus 260, 315:
1 Power chuck
1 Set of base jaws
3 Mounting screws
1 Jaw change key
1 Operating manual
1 Short operating manual
1 Mounting wrench

Technical data
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6 Technical data
6.1 Chuck data
ROTA THW plus 165-43 185-52 215-66 260-81 315-104
Max. actuating force [kN] 30 36 46 65 90
Max. clamping force [kN] 45 64 82 115 160
Max. rotation speed [min-1] 6000 5700 5400 4000 3600
Stroke per jaw [mm] 5.9 6.7 7.4 8.2 8.6
Piston stroke [mm] 20 23 25 28 28
Through hole [mm] 43 52 66 81 104
Weight [kg] 14 18 26 45 70
Operating temperature 15 – 60°C
Centrifugal torque of the base
jaw
with fine serration
McGB [kgm]
For the THW plus chuck, it is necessary to specifically
determine this data. Examples of calculation can be found
in the "Technology" chapter of the SCHUNK lathe chuck
catalog and in the "Chuck jaws in special design/
technology" chapter of the SCHUNK chuck jaws catalog.
These catalogs can be downloaded at schunk.com.
The maximum permissible speed for special machining has to be
defined by the user on the basis of the required clamping forces.
This speed must not exceed the maximum speed of the chuck.
Length of warranty 24 Months
Maximum clamping cycle number 500 000 Cycles
Tab.: Warranty and maximum clamping cycles
Ensure minimal weight for all jaws.
For unhardened top jaws or chuck jaws in special design, the
permissible RPM according to VDI 3106 must be calculated for the
respective machining job. Whereby the recommended maximum
speed must not be exceeded. The values calculated must be
checked by means of dynamic measurement using a clamping
force tester.
6.2 Clamping force / speed diagrams
The diagrams refer to 3-jaw-chuck.
Clamping force/RPM curves have been determined by using hard
jaws. In the determination process, the maximum actuating force
was applied and the jaws were set flush with the outer diameter
of the chuck.
The chuck is in perfect condition and lubricated with SCHUNK
LINOMAX plus special grease.

Technical data
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If one or more of these prerequisites is altered, the diagrams will
no longer be valid.
Chuck setup for clamping force/RPM diagram
Clamping force / speed diagrams ROTA THW plus 165-43
Clamping force / speed diagrams ROTA THW plus 185-52