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- 1 -
NORDMANN Tool Monitoring
• Control-integrated tool monitoring for open CNC control panels
• Sensors for monitoring micro tools by the measurement of the acoustic emission
• Integrated acoustic work piece dimension control (patented)
• Gap elimination for grinding
• Non-contacting measurement technology(inductive and by radio waves)
• Acoustic emission measurement based on a jet of cooling lubricant acting as an acoustic wave conductor
Experience since 1989 in the field of tool monitoring and process control systems for
all types of cutting machine tools
Our program:
- 2 -
NORDMANN Central Locations
Nordmann International GmbH
8808 Pfäffikon, Switzerland
Nordmann GmbH & Co. KG
50354 Hürth, Germany
Manufacturing:
- Tool Monitor units
- Effective power units
- Acoustic Emission Processor units (SEP)
- Distribution and service south Europe
Headquarters:
- Sensor production
- Custom-made products
- Central of distribution service
- Coordination and distribution further branchoffices in USA, China, India and Korea
- 3 -
Where tool monitoring happens (examples)
Multi-spindle drill heads Automatic multi-spindle lathes CNC lathes Rotary cycle machines
Machining centers Dressing of grinding wheels Roll grinding machines Transfer lines
- 4 -
Functions of the Tool Monitor for turning, drilling and milling
Tool and machine protection
Quality assurance and avoiding of scrap
More work pieces per hour
▪ Tool breakage detection in the moment of the breakage
▪ Tool wear detection to prevent tool breakage
▪ Detection of incorrectly clamped work pieces.
▪ Detection of false blank dimensions.
▪ Toll wear detection to ensure the quality of the workpiece
▪ Machining time reduction through the option of increasing the cut value without danger
▪ Reduction in air cutting thanks to fast reacting detection of the start of the cut (main use is grinding)
- 5 -
References (Examples)The following list is a small selection of companies that trust Nordmann tool monitor systems.
We have sold more than 15250 systems worldwide (current status Oct. 2019). Our export share is 40%.
Machine tool manufacturer Machine tool users
* We are listed in the user requirement specifications of these companies
Atlas Copco
Audi
Austrian Airlines
Berger
BMW
BorgWarner
Bosch
Braun
Brueninghaus
Burgmaier
Christian Weber
Chopard
Continental
Daimler *
Danfoss
Delphi
Deutsche Star
Deutz AG
Dom
Erkert
EVVA
FAG
Fertigungst. Nord
Fischer Werke
Ford
Galsterer
General Motors
Getrag
Geze
GKN
Häring
Harley-Davidson
Heimeier
Hero Honda
Hewlett Packard
Harting
Hilti
INA
ITT
Keso
Lego
Lucas
LuK
Mahle
MAN B+W Diesel
Mesa
Motomak
NGK
Oberndörfer
Océ
Oerlikon Enka Tecnica
Opel
Philips
Quinn Scheuerle
Rexroth Star
Röhm
Schäffler *
Scheufele
Schneeberger
SFS
Siemens
SKF
Spicer
Stihl
Straumann
Textron
Thyssen Guss
TRW
Viega
Visteon
Voss
VW *
Winkhaus
ZF
Krause-Mauser
Kummer
Magdeburg
Meccanicanova
Mikron
Overbeck
Pfiffner
Precitrame
Riello
Sala
Schaudt Mikrosa
Schütte
Siemens
Spinner
Studer
T-Mech
Technica
UVA
Variomatic
Vimacchine
Witzig & Frank
Buderus
Carl Benzinger
Chiron
Citizen
Gildemeister
EMCO
Ernst Grob
Eubama
EWAG
Hage
Höfler
Hüller-Hille
Imoberdorf
Index
I.T.S.
Ixion
Kapp
Ketterer
Klingelnberg
Krause- Mauser
- 6 -
Car manufacturers place their trust in NordmannThe following car manufacturers have included Nordmann in their “ Process Monitoring“ Functional Specifications:
Nordmann was chosen on the basis of comparative evaluations in respect of measured value quality,
monitoring strategy, ease of use, operator acceptability, service response and price.
Other car manufacturer as Audi, BMW, Ford and GM (Opel) also use Nordmann, however without
explicit reference to that effect in a functional specification.
- 7 -
Configuration of a tool monitoring system
Effective power
and torque
Force
Acoustic and vibration
Tool length & work
piece position control
Tool position control
Ethernet
PC
NC control panel
Display with touchscreen
Tool Monitor
SEM-Modul-e
Measuring element Control device Visualization
Digital drive data
(torque, effective
power, current)
Profibus / Profinet
Digital
measurement
Analog measurement
and operating unit
Work piece dimension
control
- 8 -
In-process and post-process tool monitoring
In-process tool monitoring
Indirect control during machining
with effective power, cutting force or acoustic emission
Post-process tool monitoring
Geometric control of the tool cutting edge
before or after machining with buttons, light barriers
or similar devices
For:
- The measurement does not extend the production time.
- The machine is stopped at the moment of tool breakage.
- Relief of machine operator in terms of “ear to the process”
- Recognition of process errors through viewing
measurement curves
- No additional installations (e.g. swivel buttons)
required near tool.
-Wear-resistant sensors.
Against:
- Does not offer 100% detection reliability for all tools and
breakage types.
- Sometimes the breakage is only noticed at the start of the cut
of the next work piece, e.g. screw tap breakage control with
effective power and breakage at the moment of direction
reversal.
For:
- Sometimes higher break detection reliability.
- Normally easy to use.
Against:
- The measurement can extend the production time.
- The machine is only stopped after tool breakage, i.e.
after damage to the work piece or the machine or tool
holder due to breakage forces.
- Not all test methods are without wear.
Rule of thumb: Check tools during the process. Small tools may
also be inspected post-process or must be checked in part post-process.
- 9 -
Konzept Tool Monitor SEM-Modul-e
• für alle Maschinentypen (z. B. CNC-Drehm., BAZ, Rundtakter, Mehrspindler, Schleifmaschine)
• für alle Sensoren (z. B. Kraft, Leistung, Schall, Laser)
• für alle Überwachungsstrategien (Hüllkurven, statische und dynamische Auswertung etc.)
Nur ein System mit nur einer Bedienerführung für alle Maschinentypen
Einer für Alle
Identische Oberfläche
Identische Bedienung
Nordmann-Display
CNC-Bedienfeld (hier: Sinumerik)
- 10 -
Functions of the Tool Monitor for turning, drilling and milling
Tool and machine protection
▪ Tool breakage detection
▪ Tool wear detection
▪ Collision detection
▪ Unbalance check
More work pieces per hour
▪ Machining time reduction through the option of increasing the cut value without danger
▪ In-process breakage detection saves additional testing time
▪ Reduction in air cutting thanks to fast reacting detection of the start of the cut (main use is grinding)
▪ Triggering withdrawal of the tool when completion of the cut is detected (through holes, cutting through half-finished products)
Quality assurance and avoiding of scrap
▪ Detection of incorrectly clamped work pieces.
▪ Detection of false blank dimensions.
▪ Dimension control of the finished part inside the machine.
▪ Envelope curves detects process deflections and can thereby avoid of scrap
- 11 -
Straight limits Envelopes
✓ Tool breakage detection
✓ Cut start recognition (for rapid air cutting monitoring,
especially when grinding)
✓ Special minimum limit for checking whether tool is available
✓ More precise tool breakage detection that with straight limits
Specifically for monitoring mult-spindle drill heads with
effective power measurement in conjunction with smooth
envelope matching (Autolearn)
Application of straight limits: Application of envelopes:
“Straight limit” over curve
“Straight limit” under curve Minimumlimit
Curve section to calculate the mean height
Upper
envelope
Lower envelope
Above mean height
Below mean height
Curve section to calculate the mean height
Monitoring strategies and limit values for measured curves
- 12 -
Limit over mean height
Trend display of the mean height (tool wear)
For better tracking of the behavior of the "mean height" across a larger number of workpieces, it can be represented as a
"trend" over the number of machined workpieces. This makes it easier to determine whether a tool effects an even
increase of the measured values with the number of workpieces produced, or whether it is necessary to add an averaging
of the "mean height" across several workpieces.
Limit over
mean height
Mean height
of last work piece
Tool blunt
New (sharp) tool
0
3
5
6
[kW]
2
1
4
- 13 -
Rectified dynamic portion (option)Dynamic portion (option)
Monitoring jump-like changes and waviness
Use of dynamic portion: Use of rectified dynamic portion:
✓ Breakage recognition when turning with offset and hardness
fluctuations, when a sudden measured value increase needs
to be monitored independently of a measured value drop.
✓ Recognition of out-of-true running of a milling cutter due
to individual tooth breakage.
✓ Chatter and undulation recognition during grinding.
✓ Breakage recognition when turning with offset and
hardness fluctuations.
Upper envelope
Lower envelope
Upper envelope
Above mean height
- 14 -
Gliding Reference Limit
WLM-3
Application example multi-spindle drill head:
Allows for breakage monitoring of several drill bits driven by a common motor via
effective power measurement.
Original problem: Changes in measured value height due to the breakage of a single
drill bit are smaller than changes due to the wear of all drill bits. Thus, fixed envelopes
are not violated.
Solution: Gliding adjustment of the envelope limits from workpiece to workpiece to the
changes in measurement curve height due to tool wear. This allows for a much smaller
distance between envelope and measurement curve.
The envelope follows, at a percentage distance (e.g. ± 5 %), an "averaged
measurement curve" obtained by averaging across the last workpieces.
All 6 drill bits sharp All 6 drill bits half blunt All 6 drill bits blunt1. Workpiece 250. Workpiece 500. Workpiece
502. WorkpieceAll 6 drill bits blunt, 1 drill bit breaking
Fixed envelopes
Sliding envelopes continually readjust from workpiece to workpiece.
1
2
1
-5%2
2
2
1
1
2
2
1
1
22
1
11
3
2
+5%
breakage!
3 Averaged measurement curve (temporary enlarged after changing a new sharp tool)
3
- 15 -
Tool Monitoring Requirements
• Few operating steps/options
• Few operating controls (“buttons“)
• Few indicator readings (black box)
• Good measured values even with small tools
• Recognition of even most minimal tool breakages
• Reliable wear detection
• Irrespective of working material hardness or offset
fluctuations
• Monitoring of individual drill bits in multi-spindle drill heads
User-friendliness (general view) Sensitivity
Constant conflict between user-friendliness and sensitivity
- 16 -
Operator-friendliness and sensitivity “under the one hat“
• Self-explanatory pulldown menus
• Operator and task-related switching off (hiding) of unneeded
menus
• Measurement curve display shows process errors at a mere
glance
• Graphic settings option of limits using the mouse or touch
pen in touch screen (edit image)
• Automatic limit value correction with acknowledgement of
repeated false alarms
• Sensors for monitoring the smallest tools (to Ø 0.05 mm)
• Envelopes as limits with or without automatic adjustment
to creeping measured value changes
• Evaluation of static and dynamic signal sections each with
its own measurement curve
• Wear detection with mean measurement curve height,
averaged over several workpieces
SensitivityOperator-friendliness
- 17 -
Manual adjustment of the envelope curves at the touchscreen by finger
- 18 -
Die Grenzen sollen unverändert bleiben
Alle Grenzen sollen sich
an die Messkurve anpassen
Die verletzte Grenze soll sich automatisch
an diesen Alarm anpassen
1.) Grenzen anpassen?
Bitte wählen Sie aus:
Dieses Programm neu lernen
5.0
12.5
20.0
27.5
35.0
42.5
50.0
0.0 0.0 0.0 0.0
0.0 1.59 3.19 4.78 [sec] 7.970.0
1.0
2.0
3.0
4.0
5.0
6.0
[kW]
0.0 1.59 3.19 4.78 [sec] 7.970.0
1.0
2.0
3.0
4.0
5.0
6.0
[kW]
Automatische partielle Grenzwertkorrektur
nach falschen Alarmen (SEM-Modul)
1.) Messkurvenanzeige beim Alarm
Vorteile der autom. Grenzwertkorrektur
Die Hüllkurve wird nur bzgl. der
Störung durch den Spänestau
angepasst.
Eine bis dahin vorgenommene
Optimierung der Grenzwerthöhe
wird dabei nicht gelöscht.
Spänestau beim Bohren
führt zu Fehlalarm
Autom. Korrektur der Hüllkurve entspre-
chend dem Ausreißer durch Spänestau
2.) Möglichkeiten der Alarmquittierung
3.) Ergebnis nach Alarmquittierung
ALARM
- 19 -
Bedienung über Pulldownmenüs und Softkeys
Klar strukturierte, bedienerbezogene
Pulldownmenüs
Innerhalb der Menüs werden alle
Einstellungen erläutert.
Bedienerbezogene Softkeys für
häufig benutzte Funktionen
[kW]
- 20 -
Benutzerverwaltung (Group Management)
Bedienerbezogene Nutzungsrechte
• 4 Bedienergruppen mit sinnvoller
Standardkonfiguration
• Möglichkeit der Änderung
dieser Konfiguration kundenseitig
je nach Bedarf
Erstellung benutzerbe-zogener
Softkeys für schnellen Zugriff auf
Menüs
- 21 -
WLM-3
WLM-3
PDA
SEA-Mini(acoustic emission measurement)
WLM-3S(three phase effective
power measurement)
WLM-3S(three phase effective
power measurement)
SEH(acoustic emission
measurement)
Possible sensor positions for tool monitoring in CNC lathes
cooling
lubricant
- 22 -
SEH
Work piece
WLM-3
APS-L
(acoustic emission
measurement via jet of
cooling lubricant as acoustic
wave conductor)
SEH
cooling
lubricant
Jet nozzle
coolant jet as barrier (patented)
WLM-3S(three phase effective
power measurement)
Possible sensor positions for tool monitoring in machining centers
- 23 -
SEH
Kühlschmierstoff
SEA-Mini
WLM-3SWLM-3
SDS
(acoustic
emission
measurement)
(coolant jet as
barrier)
cooling
lubricant
(acoustic emission measurement)(acoustic emission conductor made of spring steel)
Possible sensor positions for tool monitoring in transfer lines and rotary transfer
machines
(effective power
measurement)
WLM-3SWLM-3 (effective power
measurement)
- 24 -
SEA-MiniSEH
Vors
chub
WLT
PDA
(acoustic
emission
measurement)
(feed force
measuring via
the bending of
the rocker arm)
(feed force
measuring via the
compression
of the feed rod)
(acoustic
emission
measurement)
cooling
lubricant
(work piece length control measurement)
Possible sensor positions for tool monitoring in multi-spindle automatic lathes
DMS-Kralle
- 25 -
Tool monitoring system SEM-MODUL-e connected with the Profibus in
sinumeric controls 840D(sl)
Terminal block for 8 additional
sensors for measuring force,
acoustic emission, pressure,
path distance, laser light
shadowing and ultrasonic drill
length control
Exchange of control
signals and transmission
of actual values for
power, torque and
current (8, 16 or 24
spindle and feed drives
of 1 SEM-MODUL-e can
be evaluated)
Software
for viewing
Tool Monitor
SEM-MODUL-e
Profibus DP
Ethernet
Siemens-Sinumerik-HMI
NCU 7x0
Control
software with
additional
technological
function
Siemens
CNC-Unit
- 26 -
Modern design with „Apps“
- 27 -
Visualisation of the Tool Monitor SEM-MODUL-e on aSiemens Sinumerik 840 D
- 28 -
New Tool Monitor SEM-MODUL-e
“-e” for:
• evolutionary
• easy operation and ergonomic
• extremely powerful
• efficient production of monitored
machine
• ethernet connection
• extended measurement curve display
(multiple measurement curves
simultaneously)
New features relative to the last SEM-Modul:
• Displays up to 36 measurement curves in parallel (here: 4 measurement curves), can monitor up to 50 measurement curves
in parallel
• Allows monitoring of up to 4 time-independent operating machines (or stations)
• 3 Profibus interfaces for recording internal drive data and for exchanging control signals
• Visualisation and operation on a 10.4” touchscreen (previously SEM-Modul: 5.6"), or on a tablet via WLAN (with VNC viewer)
• Fully networkable and fully integrated into the intranet or Internet, including remote access
• Simple data backup via Ethernet or USB stick
- 29 -
SEH (Standard)SEH (Maxi) SEH (Mini)
SEH Acoustic Emission Hydrophon
- 30 -
Sound emission hydrophone SEH for acoustic emissions from rotating drills
- 31 -
Sound emission hydrophone SEH for acoustic emissions from rotating drills (former patent Nordmann DE 36 27 796)
- 32 -
Wirkleistungsmessgerät WLM-3S
„S“ steht für:- Per Steuersignal veränderbare Verstärkung für den Strom-Messwert
- Strom-Übersteuerungsanzeige warnt bei zu hoher Verstärkung des Strom-Messwertes
- Höhere Stabilität des Messkurve (weniger Welligkeit und Rauschen)
- 33 -
Spindle power P40%DR [kW]
0
1
2
3
4
5
0 2 4 6 8 10 12 14 16 18 20 22 24 26 28 30
Monitorable drill diameters for good motorspindles
D [mm] ≥P40%ED [kW]
2
Monitorable minimum drill diameter
Drill
dia
me
ter D
[mm
]
- 34 -
Vergleich analog gemessener Wirkleistung
mit internen Antriebsdaten
Wirkleistungsmessgerät WLM-3S Wirkleistungsmessgerät WLM-3
Per Synchronaktion aus Sinumerik
840D gewonnener WirkleistungswertPer Compile-Zyklus aus Sinumerik 840D
gewonnener Wirkleistungswert
- 35 -
Vergleich digitale Antriebsdaten / analoge Wirkleistungsmessung
bzgl. der Auswertung schneller Messwertveränderungen
Digitales Drehmoment per Profibus vom
NC-Rechner an Tool Monitor übertragen
Dreiphasen-Wirkleistungsmessung
(gemessen mit WLM-3S)
• Werkzeug: Bohrer Ø 8 mm
• Maschine: Index ABC Speedline
• Messung: z-Achse
Die direkte Messung der Wirkleistung ist der Auswertung des
digitalen Drehmoments bzgl. der Erkennung schneller
Messwertveränderungen (Bruch, Rattern) überlegen!
Rattern nicht sichtbar
Fazit:
Prozess:
Rattern sehr
gut sichtbar
- 36 -
Measuring point : 01
Cut: 01
Effective power
Measuring point : 01
Cut: 01
Effective power
Measuring point : 01
Cut: 01
Effective power
Measuring point : 01
Cut: 01
Effective power
Evaluation of the dynamic of the effective power to detect milling head tooth
breakage
Milling head dull, but no tooth broken 1 milling head tooth broken, breakage of other
pieces during cutting
Dynamic
Dynamic portion of the effective power
Dynamic
Effective power of the spindle motor
8 blade cutter
head of
Ø 80mm
- 37 -
Aco
ustic e
mis
sio
n
Time
(acoustic
emission
measure-
ment)
SEHDrill
Ø 1mm
Coolant jet
as a acoustic
conductor
Chip removal signal measurement with an acoustic emission hydrophone
on the drill
- 38 -
Breakage
Measuring point : 01
Cut: 01
Acoustic
tool burst (0,2mm)
(acoustic
emission
measure-
ment)
SEHDrill
Ø 1mm
Coolant jet
as a acoustic
conductor
Measured value of the acoustic emission hydrophone during breakage of a
0.2mm piece of a conic nozzle drill
- 39 -
Drill dull
Breakage
The last 4 holes drilled with the increase in
measured values and breakage
Breakage
Drill dull
Last normal
hole
drilled
Time (s)
Ac
ou
sti
c e
mis
sio
n (
dB
)
Time (s)
Ac
ou
sti
c e
mis
sio
n (
dB
)
Development of acoustic emission until drill breaks
Example: Drill with Ø 3mm acoustic emission recording from machine table with SEA
- 40 -
Acoustic emission measurement (sensor SEH) directly on the tool with a jet of
cooling lubricant as acoustic wave conductor in various machines
Vierspindliger
Gewinde-
bohrkopf
Sensor SEH: Körper-
schallaufnahme
über einen Kühl-
schmierstoffstrahl
am Werkstück oder
Werkzeug
Machining center
CNC lathe
Multi-spindle lathe Rotary cycle machine
SEH
Drill Ø 1mm
SEH
Lathe tool
SEH
Drill Ø 0,8mm
Four spindle
thread drill head
Sensor SEH: Acoustic
emission measuring on the
work piece with a jet of
cooling lubricant as
acoustic emission
conductor
- 41 -
Acoustic emission with the jet of cooling lubricant from the work piece
Measuring point : 01
Acoustic
Measured value of the acoustic emission hydrophone during breakage of a
3mm drill in a 6-spindle drill head
- 42 -
Vertical stream of oil
as acoustic conductor
(approx. 30 cm long)
Acoustic emission
hydrophone SEH
work piece
Breakage on
the roller
Detection of breakage on toothing hammer
- 43 -
Detection of flaking on rolling tools (Profiroll)
Alarm display of acoustic emission signals on breakage:
Breakage peak
Breakage
Breakage
Expansion options:
Force measurement with strain gauge claw for double
protection!
Evaluation method: Display of the increased dynamic
portion of the rolling force due to break out during rolling of
the next work pieces.
- 44 -
monitored
lathe tools
SEA-Mini(acoustic
emission
measurement)
SEA(acoustic emission
measurement)
Acoustic emission measurement on tool with SEA sensor
Acoustic emission sensor on the tool holder in an
automatic multi-spindle lathe
Acoustic emission sensor directly on the tool
during collector turning
- 45 -
Vorschubkraftmessung in kurvengesteuerten Mehrspindeldrehautomaten
mittels Dehnungsaufnehmern auf den Kulissenhebeln
BDA-Kralle
DMS-Kralle
PDA
Messprinzip: Dehnungsmessstreifen
Befestigung: Anschrauben M5 (5 Nm)
Einsatz bei Erfordernis einer hohen
Empfindlichkeit bei längerer Messungs-
dauer
Messprinzip: Piezoelektrisch
Befestigung: Aufkleben
Einsatz bei Erfordernis einer
höchsten Messempfindlichkeit bei
kurzer Messungsdauer und bei
nicht bekannter oder variabler
Kraftrichtung
Messprinzip: Wirbelstrom
Befestigung: Anschrauben M5 (3 Nm)
Einsatz bei geringer Anforderung an die
Messempfindlichkeit bei längerer
Messungsdauer
Messempfind-
lichkeitTemperatur-
driftabstand
Maximal
messbare
Dehnung
- 46 -
monitored drill
BDA-Kralle(feed force measurement)
Force measuring on the feed rod in multi-spindle automatic lathes
- 47 -
✓ Assembly surface does not need to be prepared
✓ Independent of the torque from the mounted screw (M5)
✓ Highly sensitive (1 nanometer)
Advantages of the BDA-Kralle strain gauge
- 48 -
Strain and force sensor PDA
Benefits:
• Fixed with adhesive (instead of screws)
• Same sensitivity in all directions, so it is not necessary to know the exact direction of the strain to be measured
• Tool-oriented attachment possible thanks to compact design (diameter 16 mm, height 8 mm)
- 49 -
Werkzeugbruchkontrolle für das Drehräumen von Kurbelwellen
Messprinzip:
Kontrolle der Schnittkräfte über eine Dehnungsmessung am Fuß des Revolverkastens
Überwachungsstrategie zur Schneidenbruchkontrolle:
Gleitende Anpassung der Hüllkurvengrenzen von Werkstück zu Werkstück an die Veränderung der
Messkurvenhöhe infolge Werkzeugverschleiß, Vorbearbeitung, Werkstoffhärte, Aufmaß und Temperatur. Damit
bleibt der Abstand der Hüllkurve zur Messkurve relativ konstant. Die Hüllkurve orientiert sich hierbei mit einem
prozentualen Abstand an einer “Gemittelten Messkurve”, die durch Mitteln über jeweils die letzten Werkstücke
gebildet wird.
Gebrochene
Schneidplatte
Dehnungsaufnehmer
DMS-Kralle
Gemittelte Messkurve als Basis für
die gleitende Anpassung der Hüllkurve
Aktuelle normale Messkurve
(Schneide in Ordnung)
- 50 -
Was Werkzeugüberwachung mit einer Kraftmessung leisten kannam Beispiel des Ausbruchs von CBN-Platten beim Hartdrehen
Bruch
Bruch
Bruch
Bruch
Dynamischer Anteil
Dieser Bruch hinterließ im Werkstück
einen Durchmessersprung von 7µm
(= Stufe von 3,5µm)
Passivkraft von Bruch 1
Dieser Bruch hinterließ im Werkstück
einen Durchmessersprung von 10µm
(= Stufe von 5µm)
Passivkraft von Bruch 2
Dynamischer Anteil
Originalmesswert Originalmesswert
- 51 -
Multi-spindle drill head with toque sensor
Torque sensor
DMA
With the DMA, the torque acting on its measuring
shaft can be measured bidirectionally both at
standstill and during rotation.
The signalling wave, the non-contact signal
recording of this wave, as well as the signal
conditioning are integrated.
Measuring principle / applications
Drilling spindles
to be monitoredBenefits
- Bidirectional measuring range (2.5 – 500 Nm)
- High repeatability (<± 0.1%)
- Low current consumption during measuring operation
(<10 mA)
- 52 -
Control of the crackling noise when the
corindon particle impacts on the deflector
plate in front and in back of the work piece.
Breakage control for honing on Hurth
Measuring principle:
Sensor:
Acoustic emission sensor NF-SEA
- 53 -
Principle of acoustic work piece dimension control (Patent Nordmann DE 197 15 634)
Work piece (rotating) Acoustic emission sensor
(SEA mini)
Upper tolerance limit of the work piece
= path of movement of the test tool
Test tool
(turning cutting plate) SEA mini acoustic
emission sensor Principle:
As soon as the turning tool touches the surface
of the rapidly rotating work piece, a frictional
sound = contact signal is generated
Benefits:Turret box
✓ Robust, because there is no need for sensitive buttons
✓ Repeatability accuracy 1 μm
✓ inexpensive
✓ fast
- 54 -
Workpiece measurement check (patented procedure) using the example of a
thread check
Test cut (turning tool)
Turned contour to
be checked
(e.g. thread)
Work piece
measurement check
via friction acoustic emission
on a test cut on the turned
work piece
- 55 -
"Slipping"
on work piece
without additional feedIncre
ase b
y
40 d
B =
facto
r 100!
1μm 1μm 1μm 1μm 1μm
Measured value during scan Scan in x-direction (lathe tool on rotating work piece)
Acoustic work piece dimension control
- 56 -
Work piece length control in the multi-spindle lathe using the WLT length
sensor
Measurment method:
The work piece length sensor checks in the multi-spindle lathe between two sites along the workpiece as
workpieces continue to cycle. Here the work pieces touch the convex forward edge of a spring-mounted
measuring piston which is pressed backwards accordingly.
Advantages:
- Detects insufficient feed of the bar
- Detects whether work pieces have been pressed into chuck by machining
- Considerably more robust thand the BDA-Pilz work piece length sensor including specified breakage point in
fixing screw
- Easily adjusted to different work piece lengths as mounted on a rail
workpiece WLT length
sensor
- 57 -
Closed process diagram for grinding and dressing
Grinding
- Controlled switchover air cutting/roug
turning/finish machining/spark-out/rapid
withdrawal
- Control of centering with reference to even
wear on the grinding disk when gear grinding
- Feed control to maintain constant grinding
pressure and spring-off
- Touch dressing tool wear monitoring
- Detection of vibration of the dressing tool
- Control of the starting effective surface
roughness of the grinding wheel
- Reducing air cutting
- Collision detection
- Wear detection
- Concentricity control
- Imbalance monitoring
- Detection of first contact to compensate for
temperature expansion and wear of the
dressing tool and grinding wheel
- Touch dressing monitoring
Basic tasks Basic tasks
Sophisticated
Dressing
Sophisticated
- 58 -
SEA-Mini
RSA
SEH
SEA-Mini
WLM-3S
WLM-3
(acoustic emission measurement)
Possible sensor positions for monitoring grinding machines
(acoustic emission measurement)
(acoustic
emission measurement)
(acoustic emission
measurement)
(effective power
measurement for spindle
and feed drive)
cooling lubricant
- 59 -
Sharp
a
b
a
Dull
d
c
d
c
b
Grinding wheel
Time
1
2
34 5
6
1
2
3
4
5
6 Rapid reverse
Spark out
Finish machining
Rough turning
Air grinding
Rapid Feed
a
b
Time
Time
Ac
ou
sti
c e
mis
sio
n
Eff
ec
tive
po
we
r o
r n
orm
al fo
rce
Sta
tic
po
rtio
n
Grinding wheel
Time
Time
Ac
ou
sti
c e
mis
sio
n
Dyn
am
ic p
ort
ion
Limit values on the wear and process monitoring / examples:
a Limit for process degeneration (e.g. collision in rapid travel)
b Wear limit (monitoring of the mean height of the measurement curve)
c Limit for wear, waviness, and chatter
d Functions of this limit like c
(monitoring the mean height of
the dynamic portion of the measurement curve)
Ac
ou
sti
c e
mis
sio
n
Eff
ec
tive
po
we
r o
r
no
rma
l fo
rce
Signal from Tool Monitor
to switch to grinding feedCollision limit
Signal from Tool Monitor
to switch to rapid reverse
Ac
ou
sti
c e
mis
sio
n
Dyn
am
ic p
ort
ion
Signal from Tool Monitor
to switch to finishing feed
Fe
ed
pa
th
Examples for control and monitoring functions during grinding
- 60 -
SEH
1.2.
3.
RSA
RSA-Ring(consisting of
sender and
receiver)
RSA-2(transmit
measuring value
via spindle)
(consisting of
sender and
receiver)
Dressing
cup wheel
Dressing form roller
(acoustic
emission pickup
via jet of cooling
lubricant)
Grinding wheelGrinding wheel
Time
Touch dressing monitoring on
the profiled grinding wheel shown:
Aco
ustic e
mis
sio
n
1st
segment
2nd
segment
3rd
seg-
ment
Envelopes
(tolerance band)
Different contactless sensors for measuring acoustic emissions at dressing
- 61 -
Spark-
limit
0,5 µm1 µm 1 µm
Measuring point: 01
Acoustic
Dressing ring
SEH
Acoustic emission picked up from the dressing ring with a jet of cooling
lubricant to compensate the temperature expansion
Acoustic emission pickup with a jet of cooling lubricant (Sensor SEH) from the dressing ring for very small feeds
- 62 -
Rotating acoustic emission sensor RSA-2 for the rotor of the „Kaiser spindle“
SensorSensor
Sender
RSA-2 mounted in the Rotor
Rotor
Sensor
Rotor
Sender
Sender
- 63 -
Measuring curves of the sensor RSA-2 in the rotating dressing roll spindle for
dressing the seat contour (injection nozzle grinding)
Dressing the seat area of the grinding wheelDressing spindle with integrated RSA-2
Dressing roll
Dressing spindle
(Kaiser) with
integrated
RSA-separated
- 64 -
Examples of ring-shaped acoustic emission sensors
with non-contact measured value transmission (RSA ring)
RSA ring, example 1 RSA ring, example 2
Rotating acoustic emission
sensor and sender
RSA ring receiver RSA ring receiver
Rotating acoustic emission
sensor and sender
Distance between sender and receiver 0.5 to 2.0 mm: Mounted in injector grinding machine
Rotating acoustic
emission sensor
and sender
Rotating acoustic emission
sensor and sender
Work piece
(Injector)
RSA
ring receiver
Receiver
- 65 -
Measuring curves of the sensor RSA-Ring at dressing and grinding injection
nozzles on UVA grinding machines
Grinding of the plane
face
Grinding of the seat
Dressing the drill hole grinding disc Grinding the drill hole
- 66 -
Tool Monitor SEM-B3
• Kontakterkennung Schleifscheibe/Werkstück mit Vorschubumschaltung zum
beschleunigten Überbrücken des Luftschleifens in Verbindung mit Körperschall-
oder Wirkleistungsmessung.
Häufigste Anwendung:
Schalttafeleinbaugerät mit Digital- und Leuchtbandanzeige der Messwerte
• 4 separate Grenzwerte, die auf Über- und Unterschreiten reagieren
• 5 Optokopplerausgänge
• Einstellbare Glättung des Messwertes
- 67 -
✓ Extensive sensor palette for the most divergent measurement values and areas of application. Therefore even diffficult
monitoring tasks can be solved (e.g. miniature tools, multi-spindle drill heads, machining in hardened material, grinding with the
smallest abrasive pencil, machines with many work stations, etc.)
✓ Upgradable as unified system on all machine controls, independent of type and year of construction, whether with or without
PC as a work station.
✓ Universal Profibus, Profinet and ethernet interface, configurable for all machine controls that can transfer internal driving
data
✓ Particularly good monitoring strategy for the recognition of the smallest breakages with turning, drilling and cutting
✓ Wear monitoring basically included in the system without extra charge.
✓ Highly user-friendly through clear menus, graphic adjustment of the limit values and automatic envelope correction
✓ Development, production, sale, mounting and service all from one company.
✓ Service worldwide and quick on-the-spot support
Why do most new users decide on Nordmann tool monitoring?
- 68 -
Reduce costs and increase productivity
by using Nordmann Tool Monitors(Sheet 1)
Main potential Basic functions of the Tool Monitor Potential savings
Work piece cost reduction of tool costs
• Longer tool change intervals due to detection of early wear
• Possibility for economic regrinding due to timely tool change
• Option for safe experimentation with different types and shapes
of tools
• Possibility of using cheaper tools, as premature end of service
may be reported
• Prevention of tool breakage and consequent "clearing" of the
tools following processing
2 - 8%
0 - 5%
5 - 15%
10 - 20%Costs down
0 - 3%
Increasing the utilisation of the
tool machine (resulting in fewer
tool machines required)
the machine cost plus the production
costs and the operator costs
• Possibility of unattended breaks run or production in a partially
supervised 3rd shift.
• Lower main time per part due to possibility to safely test higher
cutting speeds and feed values.
• The measurement curve reveals early switchover points from
express to work feed
• Trouble-free operation by avoiding breakages and "clearing" of the
follow-up stations
• Gap elimination: Reduction of the main time by driving with higher
feed speeds up to the beginning of the cut (especially during
grinding)
2 - 8%
0 - 5%
Productivity up
0 - 7%
5 - 15%
10 - 20%
- 69 -
Reduce costs and increase productivity by using Nordmann Tool Monitors(Sheet 2)
Main potential Basic functions of the Tool Monitor Potential savings
Avoidance of rejects and
rework
the machine cost plus the production costs,
operator costs and raw material costs
• In-process work piece dimension control with pneumatic measuring
probes or with a turning tool as a probe (acoustic touch detection with
the sliding noise on the rotating work piece)
• Detection of low stock or short parts, which causes an immediate stop
of the machine or activation of a scrap gate
• Improvement of the surface quality by chattering detection
• In-process tool wear and break control with immediate stop.
• The visualisation of the process on the monitor often reveals
irregularities simply by looking at the measurement curve
Productivity
0 - 5%
0 - 2%
Costs 0 - 2%
0 - 3%
0 - 3%
Protection of the machine tool the acquisition cost of the machine tool
0 - 20%• Avoidance of machine fire (when using cutting oil)
• Protection of the machine when large tools break or during a crash 2 - 10%
Avoiding complaints about
sorting out bad parts • Detection of short parts based on other process irregularities and their
sorting via a scrap gate controlCustomers aren’t lost!
- 70 -
costs
savings
Costs/savings by the use of a tool monitoring system
- 71 -
Thank you for your attention!