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Revision 1.4

TECHNICAL DOCUMENTATIONELECTRODE TIP DRESSERS

January 2007

Lutz Technik GmbH 2007

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Lutz Precision Ltd., Windsor ON 2007Errors and exceptions omitted.Reproduction and distribution to third parties is prohibited.Date of printing: January 07


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Change Index

Rev. Date Description Changed by

1.0 draft version

1.1 draft version

--------------------------------------------------------------------------

1.2 06/23/06 Modifications P. Lutzin various chapters

1.3 07/14/06 Modifications in 8.4 N. Lutz

1.4 07/18/01 Modifications N. Lutzin various chapters


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Contents1 Product Description .................................................................................................. 1

1.1 Conformance with Intended Usage............................................................ 11.2 Construction ..................................................................................................... 21.3 Function Description ...................................................................................... 3

2 Declaration of Conformance................................................................................103 Technical Data..........................................................................................................11

3.1 Electrical Operated on Pedestal ................................................................113.2 Electrical Operated on Dump Unit............................................................133.3 Pneumatic Operated.....................................................................................16

4 General Safety Instructions..................................................................................184.1 Obligation to Take Care on Part of the Owner/ Operator..................184.2 Basic Safety Measures .................................................................................18

5 Selection of the Suitable Machine Configuration.........................................195.1 General Notes on the Machine Configuration......................................195.2 Gear Box with Compliance Unit................................................................235.3 Dump Unit .......................................................................................................275.4 Controls (Optional)........................................................................................305.5 Suction and Chip Removal Units ..............................................................325.6

Rotation Query, Electrode Condition and Closing Force Measurement(Optional) ...........................................................................................................34

5.7 Dressing Tools.................................................................................................356 Installation ................................................................................................................38

6.1 General Instructions for Installation........................................................386.2 Mechanical Installation of Dump Unit....................................................406.3 Electric Installation of Dump Unit............................................................446.4 Positioning of Tip Dresser on Dump Unit ...............................................46

7 Commissioning.........................................................................................................48 7.1 Setting Up Supply and Disposal Connections .......................................48 Lutz Technik GmbH 2007

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7.2 Starting Up and Setting the Welding Gun.............................................497.3 Settings of the Dump Unit..........................................................................50

8 Optimization .............................................................................................................518.1 Usage Parameters..........................................................................................518.2 Dressing Image...............................................................................................538.3 Claiming Image and Electrode Life...........................................................568.4 Cutter Blade Wear.........................................................................................58

9

Help in Case of Faults ............................................................................................61

10 Upkeep...................................................................................................................72 11 Process Charts .....................................................................................................74

11.1 Spot Welding Dressing .............................................................................7411.2 Electrode Tip Dresser on Pedestal.............................................................7511.3 Electrode Tip Dresser on Dump Unit ........................................................76

12

MFMEA..................................................................................................................77

13 Reclamation .........................................................................................................8114 Contact..................................................................................................................82 15 Notes......................................................................................................................83


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Figures

Fig.01 Electrode tip degradation and current density.......................................... 4Fig.02 E2 Operation description.................................................................................. 5Fig.03 - Electrode tip dresser E2, Ref. 0.20.00.31V................................................... 6Fig.04 - Electrode tip dresser E2, Ref. 0.20.00.61V................................................... 7Fig.05 Dump unit for electrode tip dresser .............................................................. 8Fig.06a Pneumatic electrode tip dresser - horizontal mount............................. 9Fig.06b Pneumatic electrode tip dresser vertical mount ................................. 9Fig.07 Overview subassemblies pedestal machine ..............................................20Fig.08 Overview subassemblies dump unit machine...........................................22Fig.09a)-b) Gear box / compliance unit for pedestal machine ........................23Fig.10 Machine 0.20.00.61V w. vertical mount...................................................24Fig.11 Machine 0.20.00.61H w. horizontal mount.............................................25Fig.12a)-d) Compliance unit with extended unidirectional stroke.................26Fig.13 Electrode tip dresser, ref. 0.57.xx.61A with 90 bent arm....................27Fig.14 Electrode tip dresser, ref. 0.57.xx.61B with straight arm .....................28Fig.15 Control unit........................................................................................................30Fig.16 Suction device with venturi-jet....................................................................32Fig.17a)-b) Horizontal and vertical chip collector...............................................33Fig.18 Optical electrode monitor..............................................................................34Fig.19 Single-Blade dressing tool.............................................................................35Fig.20 Single-Blade cutter - subassemblies ..........................................................36Fig.21 Single-Blade dressing tool.............................................................................37Fig.22a)-d) Mounting positions for the dump unit .............................................41Fig.23a)-b) Examples of platforms and mounting elements ............................42


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Fig.24 Degrees of freedom on dump unit...............................................................43Fig.25 Adjustments on dump unit............................................................................45Fig.26 Adjustments relative to weld gun................................................................47Fig.27 Dressing images in case of mismatch or offset.......................................54Fig.28 Spot face profile after 400 welds ................................................................56Fig.29a)-d) Good and irregular dressing results...................................................57Fig.30 Cutter life cycle.................................................................................................59Fig.31 Dressing process / dresser on pedestal.......................................................75Fig.32 Dressing process / dresser on dump unit...................................................76


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Product Description

1 Product Description

1.1 Conformance with Intended Usage

Electrode tip dressers are intended solely for installing in automated spot-welding machines. They are used for machining electrodes according to ISO5821 (CuCrZr) by machining a pair of spot-welding electrodes in the dressingtool of the machine.

The machine is not intended for any other purpose or use - this would be

considered to be non-conformance use. In particular, we would like to pointout that

objects may not be manually processed in the dressing tool of themachine. Electrode tip dressers for manual welding electrodes are tobe used according to their instructions for use (see the manual forthe device series E2Z, L2Z)

no other components or materials, apart from spot welding

electrodes according to ISO 5821 (CuCrZr, CuZr, CuCr, CuAlO2) maybe used.

Conformance with intended use also includes reading these operatinginstructions as well as adherence to all the instructions that it specifies,especially the safety instructions. Furthermore, this also includes carrying outall of the inspection and maintenance work at the specified time intervals.

We do not accept any liability for damage to property andpersons that results from improper, non-conformance use ofour equipment or from faulty installation or impropermaintenance.

1 Lutz Technik GmbH 2007

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Product Description

1.2 Construction

Our electrode dressing equipment has a modular design. It consists of thesubassemblies dressing gearbox with axial compliance unit, an electrical orpneumatic drive, control unit and pedestal. As an option there aremeasurement systems installed for monitoring electrode geometries, gunclosing force and welding current.

For use on stationary welding guns, electrode tip dressers are mounted on adump unit instead of the pedestal. The position of the electrode dresser on

the dump units arm can be adjusted over three degrees of freedom.

By means of a bayonet quick lock system, the cutter or dressing tools canbe used for all electrodes according to ISO5821. The cutter tools have to bespecified separately from the machine example of ordering:

Electrode dresser 0.20.00.51V with cutter tool GY4,8/4-4,8/4-R8-A

The dressing tool is cleaned during and after the dressing by means of a blowoff nozzle or a suction device. The integrated venturi jet generates, fromover-pressure, air suction, by means of which the electrode particles areconveyed by positive airflow into a collecting container. The chip suctionsystem optionally includes the rotation monitor for monitoring of thedressing operation.


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Product Description

1.3 Function Description

In the case of spot-welding, the necessary heat for melting the welded partsis determined by the magnitude of the electrical current, the time for whichthe current flows and the closing force of the weld gun. Owing to thecontinuous interplay of heat and mechanical stress the profile of theelectrode cap changes. The working surface enlarges. There is also a burrformation on the periphery of the working surface. The result of this is thatas the working surface becomes larger, with a constant current, the specificcurrent density per mm

2working surface is reduced, which results in

degradation of the weld quality.

Further degradation of welding quality occurs due to the affinity of copperand zinc in the presence of heat. Thus, e.g. in the automobile industry,galvanized steel plates are being increasingly used in the automobile industryfor corrosion protection reasons. The zinc has a strong tendency to alloy withthe copper and its alloys, which are combined in the welding electrode.Owing to the external layer formation (formation of zinc layers) on the

working surfaces of the electrodes, the contact resistance increases, becauseof this energy is lost on the electrode working surface, thus affecting thereproducibility of the welding result.

To achieve a reproducible weld, a stepper function can be used to adjust thespecific current density proportionally to the working surface enlargementand the loss resistance.

Electrode tip dressers are used to restore worn spot-welding electrodes. Forthis purpose, the welding robot closes the welding electrode into the rotatingtool of the machine. Both electrodes are simultaneously brought into asuitable shape. Impurities and deformed material are removed within secondsduring this process.


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Product Description

F ig . 01 E l e c t rode t i p deg radat ion and cu r r en t dens i t y


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Compliance unit

+/- 15mm

Rotationsupervision(o tional)

Ch

Exchangeablecutter blade

w

F ig .02 E2 Operat ion desc r ip t ion


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Product Description

F ig . 03 - E l e c t rode t i p d r e s se r E2 , Re f . 0 . 20 . 00 .31V


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Product Description

F ig . 04 - E l e c t rode t i p d r e s se r E2 , Re f . 0 . 20 . 00 .61V


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Product Description

F ig . 05 Dump un i t f o r e l e c t rode t i p d r e s se r


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Product Description

F ig . 06a Pneumat i c e l e c t rode t i p d r e s se r - ho r i zon ta l mount

F ig . 06b Pneumat i c e l e c t rode t i p d r e s se r ve r t i ca l mount


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Declaration of Conformance

2 Declaration of Conformance

The manufacturer: Lutz Precision Ltd.,Windsor ON, Canada

hereby declares that the machinesdescribed below:

Electrode tip dresser on pedestal ordump unit

with electrical or pneumatic drive

Model E2,Ref. 0.20.00.31, 0.20.00.51

0.57.00.51, 0.12.00.31

Are conformant to the regulations: - NFPA 79:2002 (USTC)

- UL508 (USTC)

- EC machine directives98/37/EG and 73/32/EWG

Constructional changes that have any effect on the technical data given in

the operating manual and on the conformant usage, i.e. which significantlymodify the machine, render this declaration of conformance invalid.

1st

of May 2006

Peter Lutz,Managing DirectorLutz Precision Ltd.


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Technical Data

3 Technical Data

3.1 Electrical Operated on Pedestal

Reference

0.2

0.0

0.3

1V

0.2

0.0

0.5

1V

0.2

0.0

0.6

1V

0.2

0.0

0.3

1H

0.2

0.0

0.5

1H

0.2

0.0

0.6

1H

Bayonet cutter holder 9 9 9 9 9 9Axial compliance +/-15mm

9 9 9 9 9 9Vertical mount 9 9 9Horizontal mount 9 9 9Blow-off nozzle withvalve

9 9Chip collector with valve 9 9 9 9Rotation supervision 9 9Control unit with DeviceNet interface

9 9Pedestal 9 9 9 9 9 9


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Technical Data

Reference

0.2

0.0

0.3

1V

0.2

0.0

0.5

1V

0.2

0.0

0.6

1V

0.2

0.0

0.3

1H

0.2

0.0

0.5

1H

0.2

0.0

0.6

1H

Power rating [kW] 0.75 0.75

Rotational speed at tool [rpm] 520 520

Rated torque at tool [Nm] 17 17

Operating mode S1-100% S1-100%

Voltage [Volt] Y480 / 60Hz Y480 / 60Hz

Current drawn [Ampere] Y 3.2 Y 3.2

Air supply for suction [psi] 80 - 120 80 - 120

Air consumption [liters/second] 4-6 4-6

Volume of chip collecting container

[liter]

2.5 2.5

Mass [kg] 24 24

Noise intensity level [dB (A)]

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Technical Data

3.2 Electrical Operated on Dump Unit

Reference

0.5

7.xx.3

1x

0.5

7.xx.5

1x

0.5

7.xx.6

1x

0.5

7.xx.3

1x

0.5

7.xx.5

1x

0.5

7.xx.6

1x

Bayonet cutter holder 9 9 9 9 9 9Axial compliance +25mm (one way)

9 9 9 9 9 9Blow-off nozzle withvalve

9 9Chip collector with valve

Suction device withventuri jet and valve

9 9 9 9Rotation supervision 9 9Control unit with Device

Net interface

9 9Electric dump unit 9 9 9 9 9 9


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Technical Data

Reference

0.5

7.xx.5

1A

0.5

7.xx.5

1B

Power rating [kW] 0,75 0,75

Rotational speed at tool [rpm] 520 520

Rated torque at tool [Nm] 17 17

Operating mode S1-100% S1-100%

Voltage [Volt] Y480 / 60Hz Y480 / 60Hz

Current drawn [Ampere] Y 3.2 Y 3.2

Air supply for suction [psi] 80 - 120 80 - 120

Air consumption [liters/second] 4-6 4-6

Volume of chip collectingcontainer [liter]

2.5 2.5

Mass [kg] 80 80


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Technical Data

Reference

0.5

7.xx.5

1A

0.5

7.xx.5

1B

Degrees of freedom3 x rotational

2 x linear3 x rotational

2 x linear

Positioning radius(dressing toolarms turning point)

300 1100 mm 300 1100 mm

Cycle time for 90 movement < 3.5 second < 3.5 second

Accuracy of positioning < 0,1 mm < 0,1 mm

Mass (without tip dresser) 60 kg 60 kg

Maximum carried mass 25 kg 25 kg

Number of positions 2 (optional: 3) 2 (optional: 3)

Movement direction of armVertical /

Horizontal /Diagonal

Vertical /Horizontal /

Diagonal


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Technical Data

3.3 Pneumatic Operated

Reference

0.1

2.0

0.3

1V

0.1

2.0

0.3

1H

Bayonet cutter holder 9 9Axial compliance +/-15mm

9 9Vertical mount 9Horizontal mount 9Blow-off nozzle withvalve

Chip collector with valve

Rotation supervision

Control unit with DeviceNet interface

Pedestal


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Technical Data

Reference

0.1

2.0

0.3

1

Rating [kW] 0.6

Rotation at the tool [rpm]

Rated torque under load(about 50 % of the no-load rotational speed 200

Rated torque at tool [Nm] 35

Operating mode (unlubricated air) S3-15%

Rated pressure (flow pressure) [psi] 95

Air consumption [liters/second] 16

Volume of chip collecting container [liter] 2.5

Mass [kg] 6


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General Safety Instructions

4 General Safety Instructions

4.1 Obligation to Take Care on Part of the Owner/

Operator

The machine may only be operated by persons who are trained, instructedand authorized to do so. These persons must be familiar with the operatingmanual and act according to it. The respective authority levels of theoperations and maintenance personnel must be clearly defined.

4.2 Basic Safety Measures

Please note:

The welding machine must not be capable of operation on its own.Access to the welding and/or the protected area must be left open.Robots and other plant components should be suitably secured.

When changing tools and working on a machine, the power has tobe switched off. Work on the control units or other electriccomponents must be carried out by licensed electricians only.

Furthermore, please note that

during test runs with the suction device removed, there is apossibility of particles being thrown out at high speed, thereforeprotective eyewear must be worn.

(Tiny) electrode chips can result in serious eye injuries. To preventchips from getting into the eyes, hand gloves must be worn and/orthe hands washed carefully on completion of the work.

the electrical motor may not be opened! In instances of damage, theentire unit must be replaced.

the holes for fastening on the flange of the electrical drive arethrough-and-through holes. If excessively long bolts are used, it can

result in contact with the coil a short circuit.


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Selection of the Suitable Machine Configuration

5 Selection of the Suitable Machine Configuration

5.1 General Notes on the Machine Configuration

Our machines are built to a modular system, so that depending on the use,combinations of different dressing gear boxes with differentpneumatic/electrical drives and a large number of cutter tools are possible. Incase of welding electrodes with difficult geometries, alternative chip removalsystems and blowing devices can be built instead of the standard suction

system.Still even with all the stated variations there is maximum commonality ofparts.

The machine on pedestal for carried weld guns includes the followingsubassemblies:

(1) Steel pedestal

(2) E2 gear box with bayonet dressing tool holder and gun strokecompliance unit +/- 15 mm,

(3) Motor control unit with Device Net interface(optional, not part of ref. 0.20.00.31 and 0.20.00.51)

(4) Electric motor 480 Volt AC

(5) Chip collector unit with blow off, valve and collecting container

Cutter tools must always be specified separately from the machine.


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F ig . 07 Ove r v i ew subas semb l i e s pede s t a l mach ine


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The machine on dump unit for pedestal welders includes these subassemblies:

(1) Dump unit;

(2) E2 gear box with gun stroke complianceunit + 25 mm (one direction!);

(3) Motor control unit (3a) (slave) on dresser and control unitwith Device Net interface (master) on dump units motor;

(optional, not part of ref. 0.57.xx.51x)

(4) Electric motor 480 Volt AC;

(5) Suction unit with venturi jet, valve and 2.5 liter container;


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F ig . 08 Ove r v i ew subas semb l i e s dump un i t mach ine


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5.2 Gear Box with Compliance Unit

The gear box and compliance unit may be set up in several ways to allow bestaccess for the weld gun. The purpose of the compliance unit is to compensatepossible asymmetric shortening of the caps during a row dressing operations.The stroke of the standard compliance unit is +/- 15 mm.

In case of pedestal welders with no or insufficient compliance at the side ofthe weld gun the stroke of the dressers compliance can be increase up to 30mm (only one direction!).

The red arrows in the graphics below indicate how the weld gun may closeonto the machines cutter tool:

F ig . 09a )-b ) Gea r box / comp l i ance un i t f o r pede s t a l mach ine

Depending on how the gear box is mounted on the compliance unit there are

two versions of electrode dressers on pedestal:


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F ig . 10 Mach ine 0 . 20 .00 .61V w . ve r t i ca l mount


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F ig . 11 Mach ine 0 . 20 .00 .61H w . ho r i zon ta l mount


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Especially for use on a dump unit the stroke of the compliance unit may be

increased up to 30 mm by only using longer springs. Certainly the increasedstroke will then only be available in one direction. Depending on the positionof the two long springs there are four balancer set-ups:

F ig . 12a )-d ) Comp l i ance un i t w i th ex t ended un id i r e c t i ona l s t r oke


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5.3 Dump Unit

There are also several ways the electrode dresser may be mounted in order toserve a pedestal welder. There are two basic models: bent arm and straightarm. For each of these models there are four different configurations of thedressers compliance unit.

The position of the dresser on the arm can be optimized using the units threerotational and two linear degrees of freedom.

F ig . 13 E l e c t rode t i p d r e s se r , r e f . 0 . 57 . x x . 61A w i th 90 ben t a rm


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F ig . 14 E l e c t rode t i p d r e s se r , r e f . 0 . 57 . x x . 61B w i th s t r a igh t a rm


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In combination with the four different set-ups of the balancer there are in

total eight variations of dump units available:

Reference Arm Compliance Unit

0.57.HL.51A Bent 90 Horizontal

0.57.HL.51B Straight Horizontal

0.57.HR.51A Bent 90 Horizontal

0.57.HR.51B Straight Horizontal

0.57.VL.51A Bent 90 Vertical

0.57.VL.51B Straight Vertical

0.57.VR.51A Bent 90 Vertical

0.57.VR.51B Straight Vertical

An S in the end of the reference indicates a special version.

Example:

0.57.VR.51AS with explanation in the description special: length of roundtube 50 mm is 1.000 mm


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5.4 Controls (Optional)

The tip dressers can be supplied optionally with a control unit mounted asidethe machines motor that provides following features:

F ig . 15 Con t ro l un i t

- Start / stop of the machine (GE 3-phase circuit breaker)

- Overload protection- Supervision of 480 Volt AC supply

- Supervision of 24 Volt DC cable condition

- Device Net Interface

- Disconnect switch (lockeable)

- Internal inputs / outputs for

- valve,- rotation supervision (optional)- optical electrode monitoring (optional)


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The controls package for the dump unit consists of two interlinked units.

Both have identical features as the robotic version apart from following:

MASTER with device net interface on dump unit:

- Start forward or backward

- Automatic shut off when in final position

- Information on arms position (IN / OUT / MIDDLE)

- Secondary 480 Volt AC supply for SLAVE

- Device Net Interface

- Auxiliary (manual) start / stop of machine with handset (optional)

- Disconnect switch for BOTH MASTER ANDSLAVE. The safety switch can be secured with a pad lock.

SLAVE on electrode dresser -

- Identical to robotic version, but NO Device Net Interface.

The signal exchange takes place via the device net interface insidethe master unit.


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5.5 Suction and Chip Removal Units

The machines are either equipped with a chip collector or a suction unit withintegrated venturi-jet. The later is needed to convey debris over a longerdistance independently from gravity. For this the suction unit is also used incombination with the dump unit.

F ig . 16 Suc t i on dev i ce w i th ven tu r i - j e t

Suction device and the chip collector can be taken off withouttool by pulling on both blue knobs and sliding the part off thegear box.


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Horizontal construction(electrode holder vertical)

Vertical construction(electrode holder horizontal)

F ig . 17a )-b ) Ho r i zon ta l and ve r t i ca l ch ip co l l e c to r


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5.6 Rotation Query, Electrode Condition and Closing Force

Measurement (Optional)

Our machines can be equipped with inductive rotation supervision in thesuction head or chip collector. By operation it, it is possible to ensure that

a suitable cutter tool has been installed

the suction device or chip collector has been secured correctly

that the machine is in operation, by transmition of a pulsatingsignal. In the case of variant unit with integrated rotational speedevaluation, a check is performed to determine that the cuttingspeed is correct.

In case of critical welding tasks we recommend the use of the opticalelectrode monitor. By closing the weld gun after dressing onto this sensor itcan be assured that optimum electrode condition (fully cleaned surface,correct spot face diameter) have been achieved.

Please see the optical electrode monitors manual for detailed information.

.

F ig . 18 Opt i ca l e l e c t rode mon i t o r


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5.7 Dressing Tools

The dressing tool consists of a cutter blade (1) which is clamped in betweentwo body parts [(3) and (5)]. A colored coding ring (4) allows quickidentification.

The only part to be exchanged on a regular basis because of wear is thecutter blade (6). The dressing tool maybe exchanged within seconds due tothe machines bayonet holder.

Each cutter tool has a unique serial number and the manufacturingdate engraved.

F ig . 19 S ing l e -B lade d r e s s ing t oo l

The cutter tool is held in the gear box by means of a bayonetmechanism. There are no tools needed to take the cutter body inand out. Turn the cutter clockwise to unlock the tool. When

turning counterclockwise in order to lock the cutter a littleresistance caused by two springs can be felt.

,


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F ig . 20 S ing l e -B lade cu t t e r - subas semb l i e s

To swap the blade the two cutter bodies have to be taken apart.These are secured with two screws. The blades shoulder isasymmetric so that it cannot be inserted the wrong way.Nonetheless the shoulder is identical for all different cutterbodies. So one has to check the reference marked on the blade inorder to combine the correct references.

,


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F ig . 21 S ing l e -B lade d r e s s ing t oo l


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Installation

6 Installation

6.1 General Instructions for Installation

Our devices are supplied in cardboard boxes and/or on palettes in such a waythat there can be no damage and that transportation capacity and costs areexploited to an optimum extent. Therefore, generally, at the time ofinstallation only the electrical plug and air connections have to be connected,

Please note that optimum positioning is rarely possible in one go, generally,

several adjustments may be necessary. To achieve the correct dressing results,adjustments may be required to millimeters! Therefore, the pedestals anddump units must be mounted on a provisional basis at the start, but in astable manner.

The position of the machine within the welding facility should be soselected that

the cutter tool can be reached directly by the welding robot. Longpaths can unnecessarily increase the cycle times of the entire plant.

there can be no collisions with welding parts, robots or othermoving elements in the welding area. For checking, the entiresequence should be simulated slowly.

all machine connections -cable, hoses and piping- should be laid insuch a manner that they do not result in any stumbling points.

when laying cables and hoses, the specified bending radii must beadhered to. Abrasions can result in dangerous short-circuits andleaks. Twists in compressed air pipes endanger the operationalsafety of the chip suction system and the compressed air drives.

that the specified tightening torqueses are adhered to.

easy accessibility is always guaranteed for maintenance and repairwork. If required, climbing aids must be provided.


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Installation

As regards the mounting position, it must be noted that

the electrode tip dresser can be assembled at will. The suction of thechip removal system can point either horizontally or verticallydownwards (never upwards).

when mounted with a chip collector without venturi jet thecollecting container always has to be below the machine.

in the case of smaller designed weld guns, there is a danger ofcollision with the suction head. Mount the electrode dresser in such

a way that the welding electrode can move in through the openingin the suction head provided for the purpose.

the dump unit can be flexibly customized to the respective usageconditions with clamping elements and extension tubes. The numberof clamping elements and the pipe lengths must, however, remainreduced to a minimum for reasons of stability.

, Clamping elements and hoses must be secured in the finalposition against rotation with dowel screws and alignmentpins. Steel bases, mounting elements and leveling plates mustbe welded.


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Installation

6.2 Mechanical Installation of Dump Unit

Follow the instructions of 6.1. During mechanical installation of an electrodedresser on a dump unit make sure that

the dump unit is mounted in such way that the arm will swingperpendicular to the closing direction of the weld gun. This willmake it easier to optimize the position of the electrode tip dresseron the arm.

dressing takes place in either one of the final positions; Theelectrode tip dresser is only stable in place in either of the two finalpositions!

the moving angle of 90 can be readjusted by varying the number ofshim plates on the stopper block. Changing the moving angle of thearm also requires a readjustment of the limit switches.

the distance of the electrode dresser on the extension arm from thepoint of rotation is minimized. Unnecessarily long levers and

additional intermediate elements (e.g. more than one four-wayconnector with 500 mm cross pipe) adversely affect the dressingresults because of vibrations.

the collecting container of the chip suction is always positionedbelow the suction head during the swiveling. In addition, thecontainer should be positioned in such a way that emptying ispossible without shaking the contents. The feed pipe to the filtercontainer must be kept as short as possible.

The dump unit is already pre-adjusted when shipped. Allrelevant mechanical joints (cam shaft / final stops / positionswitch / bearings for arm) are sealed. Any change on thesepre-adjustments is done on own risk!


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Installation

Lateral, horizontal-diagonalmounting

Vertical mounting

Horizontal mounting Floor mounting

F ig . 22a )-d ) Mount ing pos i t i on s f o r t he dump un i t


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Installation

To achieve a greater degree of freedom, use the tilting and rotating brackets

from our range of products. These also have to be suitably fixed in the finalposition by welding.

F ig . 23a )-b ) Examp le s o f p l a t fo rms and mount ing e l ement s


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Installation

F ig . 24 Deg ree s o f f r e edom on dump un i t


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Installation

6.3 Electric Installation of Dump Unit

Moreover, with due consideration for Section 6.1, the following must benoted:

All the supply cables und air hoses are protected from being caughtin the swiveling axis of the dump unit or in the joints of the robotsend effector. Our dump units are equipped with a trailing cable forthis purpose.

The inductive limit switches and the controls are easily accessible.

Use only highly flexible cables.

The inductive proximity switches for the position querying (movedin/ moved out) get switched only at those exact times when theextension arm is at its respective end stop.

The dump units arm can not be moved without power

supply: the gear motor brake is locked if the motor isdeenergized.

With power being switched off the arm can only beoperated by turning the motors secondary shaft extension. While doing thatthe break has to be released by pushing the small lever on the gear motor.Due to the high gear ratio of 110:1 (201:1) manually moving the arm is easybut slow.


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Installation

Manual breakrelease

Shaft

extension

Stopper blockwith shim plates

Spring discpackage

Gear motorwith break

Limit switches

F ig . 25 Ad ju s tment s on dump un i t


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Installation

6.4 Positioning of Tip Dresser on Dump Unit

Set up the dump unit according to section 6.1 to 6.3. Move the arm into theopen weld gun and mount the electrode in such a way that

the electrode tip dresser swings in perpendicular to the closingmovement of the weld gun;

the tip dresser gear box is as close as possible to the electrode tip onthe fixed gun arm without touching it!

there is no collision with the tip dressers suction head. Adjust theorientation of the machine on the last clamp so that the electrodetip / shank may enter through the suction heads front opening.

Check carefully for any collision of the tip dresserwith the weld gun when moving the dump unitsarm in and out. Also check again for any collision

with a fully dressed down (shortest possible!)electrode tip.


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Installation

Fixed gun arm

Stroke of compliance unit

with new electrode

Stroke with electrode tip fully used up

Moving gunarm

F i g . 26 Ad ju s tment s r e l a t i ve t o we ld gun


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Commissioning

7 Commissioning

7.1 Setting Up Supply and Disposal Connections

Ensure the media supply is in accordance with the device specifications.General ly , these are:

clean compressed air for the chip removal and the compressed airdrive if present- (oil-free) of 610 bar. Preferably 10 bars.

the supply of 480 Volt AC / 60 Hz three-phase current. 24 Volt DC auxiliary power

Device Net bus cable

Check the functioning of each feed pipe in succession using the manualactuations or PLC of the system. Please ensure thereby, that

you can feel an air stream in the chip suction system, that it is

tangibly created diagonally across the dressing tool, and that thereis an air draft in front of the integrated Venturi nozzle. For checking,push the hand into the suction head, only when it is removed fromthe gearbox.

the electrical drive has the correct direction of rotation (clockwisewhen viewed from the topside of the gearbox). If the power suppliesphase are linked in wrong sequence the control unit will report an

error


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Commissioning

7.2 Starting Up and Setting the Welding Gun

Ensure that the machine has been installed according to Section 6.

The welding gun and the dressing process must now be set in such a mannerthat

the welding electrodes are aligned collinearly to one another fordressing in the way that they are aligned to the plates duringwelding. In the case of C-holders, at least one of the electrodesmust be at an angle of 90 to the machine.

in case of Quattro-Blade tools, the closing force is 1.5 kN and incase of single-blade tools, 1 kN (base setting). Starting from thisvalue, the dressing result (material removal) can be optimized later(see Section 8)

the dressing time is about 2 seconds. This value can also changesubsequently in the framework of optimization.

the cutter tool rotates BEFORE closing and AFTER opening of thewelding electrode holder. We recommend a lead running time of 2seconds and a post-running time of 5 seconds. During the post-running time, chips that have been removed are blown out andsucked away. Depending on the extent of the regular dirtying, thepost-running time can be increased up to 10 seconds.

there is no welding current present during the dressing, sinceotherwise, the dressing tool is damaged and unusable

the compliance unit of the machine is NOT actuated excessivelyduring the closing of the electrodes in the dressing tool and thereremains a stroke reserve to equalize pressure to top and bottomelectrode.

Carry out a dressing operation after the settings specified, and check thedressing result. The optimization of the dressing results matching with the

welding process is detailed in Section 8


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Commissioning

7.3 Settings of the Dump Unit

Ensure that the electrode tip dresser has been mounted on the dump unitaccording to Section 6.

Now, the welding equipment and the PLS that controls it must be set up insuch a way that

the welding gun is opened during operation of the dump unit, thereis no collision with other plant components or parts to be processed.

the inductive proximity switches for the position querying (movedin/ moved out) get switched only at those exact times when theextension arm is at its respective end stop.

in case other controls than Lutz are being used there must be anautomatic switch-off after 5 seconds of continous operation of thegear motor integrated. Otherwise the unit may be damaged in caseof a malfunction of the inductive limit switches. Also theoveramperage has to be set properly.

the position of the dump unit arm is checked prior to any furtheroperation. Especially make sure the arm is properly retracted intothe home position before any movement of the robot arm takesplace.

there is no movement of a robot arm within reach while operatingthe dum unit.


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Optimization

8 Optimization

8.1 Usage Parameters

Ensure that the electrode dresser has been commissioned according toSection 7.

In the course of optimization, what is involved is that there should be adressing image of adequate quality for the respective welding job and thatthe life of the electrode must be increased by reduced material usage.

Satisfactory results can generally be obtained in the following value ranges

(1)Gun closing force during dressing [inkN]

0.7 1.3

(2)Dressing time in case of a newelectrode (First dress)

1 3 seconds

(3) Dressing time in case of already pre-dressed electrode

1 2 seconds

(4) Electrode form ISO or similar

(5) Electrode materialCuCrZr, CuZr, CuCr,

160 Hb +/-15%

(6) Welding job / Plate coating 0.57.0 mm

(7) Welds per dressing operation 20-400

* Values referred to electrode 16mm, type B (bull-nose)

The electric electrode dresser may be used at a closing forceof up to 2.5 kN (550 lbs), but there will be significant

limitations in the dressing results: reduced electrode life aswell as increased wear of the tools and the equipment.


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Optimization

Particularly when welding high-strain steel the electrodes are stressed to a

great extent. Frequent electrode dressing with minimized material removalincreases the process safety over a constant electrode shape. At the sametime, there are fewer welding expulsions, and reworking is reduced. Steppingof the welding current can often be done away with, and makes it possible toreduce energy costs.


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Optimization

8.2 Dressing Image

The dressing image of a new electrode shows a possible mismatch in theprogramming of the welding robot. Inaccurate programming can have a veryadverse effect on the dressing result, and more especially, the electrode life:In the case of an offset-milled electrode, the cutter tool reaches its coolingcircuit too soon and the electrode collapses prematurely.

Position the electrode holder and optimize the dressing process in such a waythat

the spot face of both the electrodes is in their centre as far aspossible. In doing so, use a new electrode for every new trialdressing, since the result can get falsified by an electrode that hasalready been milled.

when dressing a round electrode (Form F according to ISO / USbull-nose), NO radius is recognizable between the electrode spotface and its flank.


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Optimization

Possible forms of the mismatch or offset, which generally appear as a

combination, are shown below:

Electrode axis Electrode axis

Turning axisdressing

Turning axisdressing

Electrode axisTurning axisdressing Electrode axis

F ig . 27 D re s s ing images i n case o f m i sma tch o r o f f s e t


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Optimization

In the optimum case, the dressing result will tally with the specifications of

the data sheet for the relevant dressing tool. Generally, however, certainvariants in the spot face diameter and the spot face radius have to beaccepted and taken into account.


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Optimization

8.3 Claiming Image and Electrode Life

High accuracy in cutter manufacturing helps minimizing wear rates down to0.07 mm per dressing operation. Our cutter tools are designed to consistentlyremove ONLY the necessary amount of material of 70-200 m. A bull-noseform B (US / ISO form F) electrode may be dressed 70 -100 times with up to15,000 welds without operator intervention.

Residues of organic plate coatings (zinc oxide) on the electrodes, whichremain behind after the dressing, can (but need not be compulsorily) lead to

process instability. Often, there is then a hysteresis effect, in which the zincoxide keeps on forming despite dressing. The spot face then has an irregularcrater pattern. From a certain coating thickness onwards, this can result inunexpected expulsion of this layer. For this we strongly recommend to havethe spot face area always fully cleaned.

In order to prevent blocking of the cutter tool in case of very heavy wear onelectrodes, we recommend dividing longer dressing cycles into several shortdressing intervals by opening and closing the holder during the dressing

process (e.g. "Interval dressing with 2x3 rotations instead of 1 x 6 rotations).The length of the chips then becomes significantly shorter especially in caseof single-blade tools.

F ig . 28 Spo t f ace p ro f i l e a f t e r 400 we ld s


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Optimization

Wear on the blade and clogging may as well lead to irregular dressing results.

For this we recommend to dress electrodes also just before changing them.These dressed caps can than be inspected while doing a cap change.

gooddressing result

baddressin results

F ig . 29a )-d ) Good and i r r egu la r d r e s s ing r e su l t s


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Optimization

8.4 Cutter Blade Wear

Slow degradation of the cutter tool and especially the cutter blade isinevitable and part of normal operation.

The cutting edge deforms during every dressing operation due to friction heatand mechanical stress. The extend of wear may vary significantly anddepends on factors such as

- dressing time

- gun closing force during dressing

- cutter rotational speed

- proper positioning of the weld gun relative to the electrode dresser

- electrode / blade profile

False dressing parameters such as too long dressing timeand too high gun force will unnecessarily shorten cutter life.The same applies to closing the weld gun onto the cutterwhile it is not rotating or using cutter tools that do notmatch the electrodes profile.


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As figure 30 shows on the example of a cutter tool for (bullnose) ISO F16 in an E2 dresser running at 560 rpm (gun force 1 kN/ dressing tim

F ig .30 Cu t t e r l i f e cyc le


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Optimization

The abrasion rate of a new cutter blade is about 0,13 to 0,15 mm per second

(at 1kN closing force and 560 rpm). Over the first 1.000 operations this ratewill drop by 20%-30% down to around 0,1 mm per second. The abrasion ratewill then only drop very slowly over the next 50.000 to 120.000 to nearlyzero.

The implication of this terrasse-shaped life cycle of the cutter blade is that

- the cutter blade has to be swapped in the moment when its

abrasion rate has dropped to an extend that welding quality is indanger

or

dressing time is step by step being readjusted in order to compensate theblades wear. The blade may be used as long as a clean spot face can beachieved within reasonable dressing time. We do not recommend thisrun-to-failure strategy since wear rates may differ from application to

application and even during a blades life cycle.


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Help in Case of Faults

9 Help in Case of Faults

Before working on the machine, please read the safetyinstructions in your own interest!

Document damage (type, time, location), to simplify therectification of the causes for yourself and for others.

Cure the cause and not just the symptoms! If similarfaults occur frequently in the same station, the

underlying causes may be a deeper one (e.g. increasedtool wear because of adhesives)

Fault Error source Measure

(1) No removal at

the electrodes,

no signal of therotation display,no running

noises of the

machine present

No 400 / 480 voltsupply

Check step-wise the powersupply.

With control unit:check for error signal powersupply

No 24 Volt controlsignal or no start signalvia bus system.

Check the programming of thePLC or signal transfer.

No 24 Volt controlsignal or no start signalvia bus system becauseof cable rupture.

Check the signal cables to themachine.


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Overload / overtempprotection of controlunit has been actuated.

Check for error message oncontrol unit. In case ofoverheating allow machine tocool down. Check the feedwires for possible short circuits.Carry out a function test withmanual auxiliary actuation atthe control unit.

With conventional controlpanels: Check the amp-settingat the overload relay and ifrequired, set afresh accordingto the motor data.

Electrical drive is faulty,since it is overloaded orin operation for too long(overheating).

Electric drive is to be replaced.The dressing parameters (gunclosing force and dressing time)should be checked and re-set ifrequired.

No power supply to thedrive, since the motorprotection circuitbreaker is faulty.

Only with conventional controlpanels:Replace motor protectioncircuit breaker

(2) No removal at

the electrodes,no signal of the

rotationsupervision,running noises

of the machinecan be heard

No dressing tool cutterhas been inserted.

The correct dressing tool shouldbe mounted.


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The bayonet locationreceptacle is damaged.

The tool receptacle should betested by unlocking and lockingagain. Check whether there istraction to the drive. In case ofdamage, the gear wheel withbayonet location receptacleshould be replaced.

The carrier on the motorshaft is damaged.

The electrical motor should betaken off and the carrier shouldbe checked. If necessary, thecarrier should be replaced.Caution: The four fasteningscrews for the drive must beset correctly.(2 x long, 2 x short), since theremay otherwise result somecontact to the coil!

The gearbox is damaged.This applies, above all,when the bayonetreceptacle does getlocked, but at the timeof rotation of the tool,

the electrical drivecannot be felt to rotateas well.

The gearbox should bereplaced. When gearboxes arereplaced, the entire set of gearswith bearings must always bereplaced.

In case of external damage tothe cover plates, e.g. caused byclosing the electrode holder onthe gearbox, the completegearbox unit must be changed.In this case, too, theprogramming of the robot hasto be corrected.


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Our machines are supplied in the following variants:

(3a) Simple (inductive) rotation detection with one LED,which supplies a pulsating digital 24 volt signal accordingto the number of contact surfaces in the tool.

(3b) Integrated (inductive) rotation supervision with threeLEDs, which evaluates the cutting speed of the deviceand on undershooting the minimum speed, switches offthe digital 24-Volt signal.


(3a) No removal orhardly any

removal at theelectrodes. Signal

of the rotationdisplay(1 LED, withspeed evaluation)present.

Cutter tool rotates inthe wrong direction.The correct direction ofrotation is clockwisewhen viewing from thetopside of the dressingtool.

Only applies when not usingour control unit:In the 400 V AC power supplyswap two phases. The phaseexchange should be carriedout in the supply and not inthe machine. As a result, thecorrect direction of rotation isguaranteed even when thedrive or the machine isreplaced.

Dressing tool isdamaged or blunt.

Replace cutter tool.

Welding gun is notbuilding up a closingforce at all, or theclosing pressure is toolow.

Check the closing force and ifrequired, set afresh.


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(3b) No removal orhardly any


of the rotationalspeed evaluation(3 LED, withrotation

supervision)present.

Cutter tool rotates inthe wrong direction.The correct direction ofrotation is clockwisewhen viewing from thetopside of the dressingtool.

In the 400 V AC power supply,swap two phases. The phase

exchange should be carriedout in the supply and not in

the machine. As a result, thecorrect direction of rotation isguaranteed even when thedrive or the machine is

replaced.

Dressing tool isdamaged or blunt.

Replace the tool.

Welding electrodeholder is not building

up a closing pressure atall, or the closingpressure is too low.

Check the closing force and ifrequired, set afresh.

(3c) No removal orhardly any


of the rotational

speed evaluation(3 LED) NOTpresent.

Cutter tool NOT

rotating or rotating

too SLOWLY (< 190

rpm) because there is

an error according to

point (1) and (2).

Rectify the problem accordingto the points (1) and (2) asdescribed.

The device does notrun with the fullcurrent on threephases (audible from

hum of motor).

The power supply has to bechecked and if required,corrected.

With control unit: check forerror message


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(4) Cutter tool getsregularly clogged;the electrode lifeis shortened.

Blowing off or suctionunit not working orworking inefficient

Check the position of theblower nozzle. The air jet mustbe aimed directly into theelectrode tip dresser.

Always install the exhausthose and collecting containerbelow the dressing unit.

The input lines for blowing outor suction should be checked.Remove any kinks in the hose.

Where possible, install theelectrode tip dresser in such away that the chip removal of

the suction system pointsvertically downwards.

Check the valve for theblowing off or the suctionunit.

There is an increased

material removal owingto the wrong dressingparameters.

Minimize the material

abrasion per dressingoperation: Reduce the dressingtime and gun closing forcewhen dressing.

If the electrode wear cannotbe reduced withoutendangering the strength ofthe spot-welding,

dressing should be done morefrequently.


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Adhesive and sealingmaterial residues

see above

Check the cutter tool regularly(electrode change) and ifrequired, replace and thenclean them.

After dressing, allow themachine to run and blow offfor a longer time.

The wrong tool typeresults in excessivematerial removal.

Check type and if required,replace it.

(5)Electrodes are

either not dressedat all even duringtheinitial run of the

device or milled

too little.

Wrong or faulty

dressing insert

Check the cutter tool and

replace if required. Importantfactors such as the radii milledin the spot face area, shouldonly be recorded withprecision measurementdevices. In case of doubt, youshould adhere to the typedesignation and thedescription in the data sheets

or consult Lutz Technik.

Cutting speed too lowbecause of gear box ormotor damage.

see (1) (3)

Closing force of weldgun is too low.

Increase the closing force insteps.

Dressing time tooshort.

Increase the dressing time insteps.


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(6) Electrodes donot get dressedat all, or getdressed too little,duringongoing

operation.

see (5) see (5)

Cutter tool clogged. Clean cutter tool.

In case of contamination withsealant clean frequently

see (4)

Cutter tool damagedbecause of weldingcurrent during dressingoperation.

Replace part

Ensure that while dressing, nocurrent is initiated.

Blades in the dressinginsert worn.

Check the part and replace it.

(7) Even thoughboth of theelectrodes are ofthe same kind,their lives aredifferent.

see (6) see (6)


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Particularly withJ-guns guns, it canhappen that anelectrode/holder arm isin contact with thedressing tool for alonger time than theother.

By changing the programmedposition ensure that both the

electrodes are in simultaneouscontact with the tool.

Depending on thewelding application,the electrodes arestressed to differentlevels. This can resulte.g. from insufficientcooling ordisplacement of theweld gun.

(8) Electrode spotface is too smalland/ ornot round.

Wrong cutter tool Check part, replace if required.

Building-up

(oscillations) of theelectrode dresserowing to unstableassembly and/ordressing for anexcessive time.

Improve the fixing on

pedestals, swivellers orgrippers, if required; useheavier pedestals.

Check compliance unit.

Use self-centring QUATTRO-BLADE cutters.

Shorten the dressing time tothe extent possible.


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(9)Chatter marks

are formed onthe electrodes.

Wrong cutter tool Check part, replace if required.

Electrode holder doesnot move over themiddle of the dressinginsert.

Check the programming andcorrect it if required.

Adjustment angle ofthe electrode whiledressing is too flat.


Building-up(oscillations) of theelectrode dresser

owing to unstableassembly inconjunction withasymmetric dressingtools (Y-BLADE,turning plate).

Improve the fixing onpedestals, swivellers orgrippers, if required; use

heavier pedestals (e.g. typeST5).

Check stroke compensations.

Use self-centring QUATTRO-BLADE inserts.

Shorten the dressing time to

the extent possible.

Electrodes are notcorrectly aligned.

Re-adjust electrode holder.

(10) Chips are notremovedcompletely.

Tip dresser stops whenthe holder is closed.

Ensure that the machine keepsrunning while opening theweld gun.


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(11) A small burrforms in themiddle of theelectrode spotface.

Small burr formation isgenerally tolerable.

Remove instabilities.(see 9)

Mostly, the effect isenhanced by unstableassembly andimprecise insertion ofthe electrode holder.

Reduce the dressing time(dressing in 2 short intervals)and increase the steppingspeed (pneumatics).


(12) In case of flatelectrodes ISOForm A or C

(viewing points)

the spot face isnot fully cleaned.

During the welding,the spot face has beendeformed into a funnelshape. A thick diffusionlayer has formed.

Parameter adjustment: The

material removal is notsufficient under the givenconditions. Therefore, thedressing time and the closingpressure should be increased insteps.

Replacement of the tool type:Check whether the requiredwelding spot diameter can alsobe achieved with a smaller spotface diameter (e.g. 12 insteadof 16 mm).


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Upkeep

10 Upkeep

It is fundamental for the operational safety of the electrode tip dresser thatno significantly large material residues should be deposited in the chipchambers of the dressing tool and in the exhaust if present. Regularcleaning prevents faults, and in general, some machines, owing to greasedeposits and adhesives in the environment, get dirty faster than others.Therefore, the following data is only for orientation. The conscientiousmaintenance technician is urged to check problem areas more frequentlythan others.

Provided that the installation is optimal and if there is an average level ofcontamination, we recommend:


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Upkeep

Interval Assembly /

part

Measure

(1) 10.000 dressingoperationsor monthly

Cutter tool Clean the cutter tool fromdebris and other residues. Checkfor any visible damage

Before inserting the tool, clean

the bayonet location.

(2) 10.000 dressingoperationsor monthly

Chip collector Clean chip collector and emptycollecting container

(3) 30.000 50.000 dressingoperationsor quarter annually

Cutter tool Replace cutter tool andexchange blade. Important: Insome applications morefrequent change of blade maybe necessary

(4) 60.000 100.000operations / half year

Machine Visual inspection of machine:

On dump unit check play in allinterlinkages, sliding bearing.Inspect spring disc package and

cabling;Check all clamps for damage(cracks)See Fig.25


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11 Process Charts

11.1 Spot Welding Dressing

Assure weld quality by keeping electrode deformation with tip dressing within controlled limits

Fig.30 Cap deformation during welding

74

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11.2 Electrode Tip Dresser on Pedestal


F ig .31 D r es s ing p roces s / d r e s se r on pedes ta l

Electrode tipdresser Ready?

Close weld gun onrotating dressing

tool;open gun after

1 - 2 seconds w hilemachine runs.

If Ready = true

thenstart dresserelse Error

Critical capcondition reached

after50 250 welds

(depending onapplication)1 2

3

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11.3 Electrode Tip Dresser on Dump Unit

Check capcondition with

optical monitormounted on

end-effector(optional!)

> 3 seconds

Electrode

dresser Ready?=no

error and armin home

position

Move dresser in

home positionand stopdresser

> 3,5 seconds 3.5 seconds 1-2 seconds 50dressingoperations/electrode

Local / Plant

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Asymmetricwear ofelectrodes

Downtimedue toelectrodechangeduring shift

3

Electrodes donotsimultaneouslyclose onto cuttertool

5 3 45

Check positioning ofweld gun; balancershould hardly moveif properly set up

Local / Plant

Cutter Tool /Chipcollector

No or littleremoval ofcontamination anddeformationon electrode

Cold welds(currentdensity toolow)

8

Cutter toolclogged due toclogged chipcollector

8 3 ##Empty chip collectoron regular basis,

Local / Plant

Electric Motor

Overheat dueto excessiveoperationtime

Downtimedue torepair(MTTR 15minutes)

8 3

a) motor ratingS1-100 withventilator2) max.operation timein control unit

1 24NONE- motor fullyprotected

Overheat dueto overload


8Too high gunforce

3

a) overloadprotection inmotor controlunitb) thermo-detectors inmotor

1 24NONE- motor fullyprotected

Blockage dueto failure ofbearings(MTBF sealedbearings >500K hours)


8 3

a) overloadprotection inmotor controlunitb) thermo-detectors inmotor

1 24

NONE-konsolidatedoperating time asdresser < 700 hoursin 5 years; motor,gear and bearings >

500K hours

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80

Electric Motor /Gear Box

Blockage dueto failure ofbearings(MTBFsealedbearings >500K hours)


8

Corrosion due toweld gunscooling waterentering gearbox

3

a) Sealedbearingsb) motor IP55c) dresserhousing Al

1 24

Home position ofweld gun NOTabove electrodedresser

Integrator

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Reclamation

13 Reclamation

The manufacturers accept no responsibility for any losses, consequential orotherwise arising from the ability or inability to use the equipment supplied.

The limit of the warranty is the repair or replacement of any faultycomponents directly attributable to manufacturing defects arising during theperiod of 12 months following purchase.

The warranty does not include damage resulting from incorrect operation ofthe unit.

In case of any damage or malfunction of our product we ask you to:

- Contact our sales service staff by phone or email.

- Add a copy of our delivery note, confirmation of order, invoice or yourpurchase order.

- Add a short description of the problem.

- We may only accept CIF return shipments.


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Contact

14 Contact

www.lutz-precision.com

[email protected]

Europe:PST Lutz Technik GmbHHildachstrasse 12-14

D - 81245 Mnchen

Phone: +49 (0) 89 820 306 0Fax: +49 (0) 89 820 306 59

North America:Lutz Precision Ltd.368 Betty Drive

Windsor, ON N8S 3W6Canada

Phone: +1 519 566 92 16Fax: +1 866 362 59 88

South America: Lutz Tcnica Brasil Ltda.

Rua Irineu Vilela Veiga, 135salas 06 e 07CEP: 89270-000Bairro Centro-Guaramirim-SCBrasil

Phone: +55 47 373 26 59Fax: +55 47 373 35 27

http://www.lutz-precision.com/mailto:[email protected]:[email protected]://www.lutz-precision.com/

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Notes

15 Notes

Documents

LUTZ_TD_E - V1 4