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Seco - Turning
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Seco Seco Core curriculum of metalcutting -- page page 11
1/56COPYRIGHT © 2008, Seco Tools AB
TurningTurning
2/56COPYRIGHT © 2008, Seco Tools AB
Turning Turning toolholderstoolholders
Seco Seco Core curriculum of metalcutting -- page page 22
3/56COPYRIGHT © 2008, Seco Tools AB
Right-handedtoolholder
Neutraltoolholder
Left-handedtoolholder
Toolholder hand, left or right?Toolholder hand, left or right?
Turning Turning toolholderstoolholders
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ANSIANSI norm for norm for externalexternal toolholderstoolholders
Page 8
Hol di ng met hodHol di ng met hod
Insert sha peInsert sha pe
Tool hol der styleTool hol der style
Insert cl ea ra nce a ngl eInsert cl ea ra nce a ngl e
Ha nd of toolHa nd of tool Pocket styl ePocket styl e
Sha nk si zeSha nk si ze
ICIC( # 1/8”)( # 1/8”)
Qua lified l engthQua lified l ength
Ma nu fa ctu rersMa nu fa ctu rers
opti onopti on
Seco Seco Core curriculum of metalcutting -- page page 33
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ANSIANSI norm for norm for internalinternal toolholderstoolholders
Ba r ma teria lBa r ma teria l
Sha nk dia meterSha nk dia meter
B ori ng ba r lengthB ori ng ba r length
Hol di ng met hodHol di ng met hod
ICIC( # 1/8”)( # 1/8”)
Insert sha peInsert sha peTool hol der styleTool hol der style
Insert cl ea ra nce a ngl eInsert cl ea ra nce a ngl e
Ha nd of toolHa nd of tool
Page 9
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ISO norm for ISO norm for external toolholdersexternal toolholders
Hol di ng met hodHol di ng met hod
Insert sha peInsert sha pe
Tool hol der styleTool hol der style
Insert cl ea ra nce a ngl eInsert cl ea ra nce a ngl e
Ha nd of toolHa nd of tool Sha nk hei ghtSha nk hei ght
Sha nk w idthSha nk w idth
Tool l enghtTool l enght
Cu tti ng edge Cu tti ng edge lengt hlengt h
Ma nu fa ctu rersMa nu fa ctu rers
opti onopti on
Seco Seco Core curriculum of metalcutting -- page page 44
7/56COPYRIGHT © 2008, Seco Tools AB
ISO norm for ISO norm for internal toolholdersinternal toolholders
Ba r ma teria lBa r ma teria l
Sha nk dia meterSha nk dia meter
B ori ng ba r lengthB ori ng ba r length
Hol di ng met hodHol di ng met hod
Insert sha peInsert sha pe Tool hol der styleTool hol der style
Insert cl ea ra nce a ngl eInsert cl ea ra nce a ngl e
Ha nd of toolHa nd of tool
Cu tti ng edge Cu tti ng edge lengt hlengt h
Ma nu fa ctu rersMa nu fa ctu rers
opti onopti on
8/56COPYRIGHT © 2008, Seco Tools AB
Negativeangle
Positiveangle
0°
Negative rake
Positive rake
Neutral rake
Rake Rake geometriesgeometries
Seco Seco Core curriculum of metalcutting -- page page 55
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Negative rake, used for steel, steel alloys, stainless steels, cast iron.
Positive rake, used for gummy materialsand some high–temperature alloys.
Neutral rake, used for threading, grooving, profiling and form tools.
Use negative rake whenever possible
Rake Rake geometriesgeometries
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The working cutting edge (entering) angle Κ influences the chip formation, chip removal direction and the size and direction of the cutting forces.
Major cutting edge and κ
Cutting Rake γ − positive gives lowcutting forces and negative gives better chip breakage.
Κ
Back Rake λ – negative gives a robust cutting edge and positive gives a weaker cutting edge.
The nose radius and geometry(minor cutting edge)influence the surface finish.
Toolholder geometryToolholder geometry
Seco Seco Core curriculum of metalcutting -- page page 66
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D type holderFirst choice for general externalturning.
For negative inserts with a central hole.
P type holderFor negative inserts with a central hole.
No clamp on the top, facilitates free chip flow
Toolholders
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C type holderDesigned mainly for Seco PCBN inserts without hole.
S type holderFor external and internal turning with positive inserts.
Toolholders
Seco Seco Core curriculum of metalcutting -- page page 77
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Choose as large a shank as possible (depends on machine)
ShankShank SizeSize
External Tool Holder
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(Typical example )
Toolholders
Seco Seco Core curriculum of metalcutting -- page page 88
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ff
Impact of (changing) entering angle.
Toolholders
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PTJNR, PTTNR
Entering angle, 93°, 60°
Insert, TN..
Toolholders
Seco Seco Core curriculum of metalcutting -- page page 99
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PVJNR
Entering angle, 93°
Insert, VN..
Toolholders
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In the case of a slender workpiece, for example,these aspects can solve a practical problem (vibrations).
Toolholder Toolholder -- cuttingcutting forcesforces
Seco Seco Core curriculum of metalcutting -- page page 1010
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MMulti ulti DDirectional irectional TTurningurning
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Advantages of MDTSmaller number of tools.
Shorter adjustment times.
Shorter insert change times.
Less extra time.
Disadvantages of MDTLonger effective cutting time due to lower cutting speed.
Evaluation of effective time versus extra time is important. Thisdepends on the batch size and complexity of the workpiece.
(share of longitudinal turning)
MMulti ulti DDirectional irectional TTurningurning
Seco Seco Core curriculum of metalcutting -- page page 1111
21/56COPYRIGHT © 2008, Seco Tools AB
Mini Shaft
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Mini Shaft
• ID Turning
• ID Grooving
• Back facing
• Chamfering
• Profiling
• Threading
Exchangeable Head Small Diameter Boring SystemExchangeable Head Small Diameter Boring System
Seco Seco Core curriculum of metalcutting -- page page 1212
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InsertsInserts
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ANSIANSI norms norms for insertsfor inserts
Insert sha peInsert sha pe
Si de cl ea ra nce Si de cl ea ra nce a ngl ea ngl e
Tol era ncesTol era nces
TypeType
IC si zeIC si ze
Thi cknessThi ckness
N ose ra diu sN ose ra diu s
Cu tti ng edge Cu tti ng edge conditi onconditi on
Chi pb rea kerChi pb rea ker
Seco Seco Core curriculum of metalcutting -- page page 1313
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ISOISO norms norms for insertsfor inserts
Insert sha peInsert sha pe
Si de cl ea ra nce Si de cl ea ra nce a ngl ea ngl e
Tol era ncesTol era nces
TypeType
Cu tti ng E dge L engt hCu tti ng E dge L engt h
Thi cknessThi ckness
N ose ra diu sN ose ra diu s
Cu tti ng edge Cu tti ng edge conditi onconditi on
Chi pb rea kerChi pb rea ker
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CuttingCutting
edgeedge
lengthlength
InscribedInscribed circlecircle
ThicknessThickness
NoseNose radiusradius
InsertsInserts
Seco Seco Core curriculum of metalcutting -- page page 1414
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The insert shape and size determines the maximum cutting depth.
InsertsInserts
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Choose as small a diameter as possible!
Choose as large a diameter as possible!
.... CONFLICT!
Length
Dia
F
Boring BarsBoring Bars
Seco Seco Core curriculum of metalcutting -- page page 1515
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Steel Densimet Carbide
Less than 3 : OK OK OK
Less than 6 : Vibration Risk of vibration OK
Less than 9 : Vibration Vibration Risk of Vibration
Greater than 9 : Vibration cannot be avoided using normal tools
Length
Dia
LengthDiameter
Overhang ratio =
Boring BarsBoring Bars
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In order to minimize vibration problems, change direction and size of
cutting force by, for example;
Entering angle = 90°Smaller nose radius and/or sharper cutting edge.Smaller cutting depth and larger feed.Change cutting speed.
Tang
entia
l
Boring BarsBoring Bars
Seco Seco Core curriculum of metalcutting -- page page 1616
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Tang
entia
l
Deformation
Practical consequence
Boring BarsBoring Bars
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The difference between milling and turning
Varying cutting forces (stress).Varying cutting temperatures (tension in insert).
Turning gradesTurning grades
Seco Seco Core curriculum of metalcutting -- page page 1717
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Toughness!Toughness!
Turning gradesTurning grades
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Turning gradesTurning grades
Economic tool life Economic tool life –– 15mins in steel & 10mins in stainless steel15mins in steel & 10mins in stainless steel
Seco Seco Core curriculum of metalcutting -- page page 1818
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Wear resistance
Toughness
NN
H
SS
P TP3000TP2000TP1000
TP2500
M TP2500 TM2000 TP40TM4000
K TK1000 TK2000
TK1000 TK2000
Turning grades Turning grades –– CVD coatedCVD coated
36/56COPYRIGHT © 2008, Seco Tools AB
Wear resistance
Toughness
NN
H
SS
P
M
K
890 883
Turning grades Turning grades –– uncoateduncoated
Seco Seco Core curriculum of metalcutting -- page page 1919
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Wear resistance
Toughness
NN
H
SS
P
M
K
CP200 CP250 CP500
CP200 CP250 CP500
CP500
Turning grades Turning grades –– PVD coatedPVD coated
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Wear resistance
Toughness
NN
H
SS
P
M
K
CMP CM
CM
Turning grades Turning grades –– CermetCermet
Seco Seco Core curriculum of metalcutting -- page page 2020
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Range of chipbreakers
1 2 3 4 5 6 7 8 9
FF
F
MF
M
MR
R
RR
MF4
RR9
R8R7WR6
MR7
R4W
R 5
RR6
MR3 MR4
M1M3W M5
MF2W
MF1 MF3
F1W
F2W
FF1
MF5
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WNMG080408W-M3
High productivity - wiperSemi-finishing and finishingTurning with very small cutting depths
Good surface finish - wiperFeed x 2 = the same surface finishThe same feed = Ra / 2
High feed inserts
Seco Seco Core curriculum of metalcutting -- page page 2121
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Copying with D- and T-style wiper insertsSince D- and T-style Wiper inserts not are designed within ISO-tolerances an adjustment in the tool offset must be made.
A deviation from the nominal nose radius shape, will always occur (D1, D2) when going towards a corner.
High feed inserts
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Inch
0.24
0.2
0.16
0.12
0.08
0.04
0.008
0.003 0.006 0.009 0.012 0.015 0.018 0.021 0.024 0.027 0.03 Inch
Feed Rate
Dep
th o
f Cut
MF2
MF5
M5
MF3
MF4F1
MR7
Application areas for chipbreakers
Seco Seco Core curriculum of metalcutting -- page page 2222
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Prevents damage to the workpiece, tool and operator.
Avoids production stoppage.
Avoids chip evacuation problems.
Application areas for chipbreakers
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Less power required to break.
Less stress on cutting edges.
Smaller increases in cutting forces.
Easier to evacuate.
Higher power required to break.
Higher stress on cutting edge.
Possible deflection & vibration.
Preferred—Short spiral chips
Avoid—Very short, tight chips
Avoid—Long, stringy chips
Extremely difficult to evacuate.
Can recut and damage the workpiece or tooling.
Application areas for chipbreakers
Seco Seco Core curriculum of metalcutting -- page page 2323
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Plastic deformation of workpiece material due to shearing. (chiplamellae or chip segments).
Most of the energy required for machining is used in the shearing surface.
ChipWorkpiece
Tool
Sheare surface
Chip formationChip formation
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Long chip materials have a flow zone on the underside. The thickness of the flow zone is influenced by the workpiece material, the machining angle and the cutting speed.
Flowzone
Chip formationChip formation
Seco Seco Core curriculum of metalcutting -- page page 2424
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May not be larger than 2/3 of the cutting edge
length and no smaller than the nose radius.
ap = depth of cut
Turning applications
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ap = depth of cut
ap influences the:• Metal removal rate (productivity).• Power consumption.• Chip formation.
ap is limited by: • Cutting edge length.
Turning applications
Seco Seco Core curriculum of metalcutting -- page page 2525
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Feed rate (inch/rev)
If the feed rate is too low, the materialwill be compressed and the contactpressure will lead to premature wear ofthe tool and a poor surface finish. f
f = feed rate (inch/rev)
Turning applications
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f = feed rate (inch/rev)
f influences the:Metal removal rate.Power consumption.Chip formation. Surface finish.
f is limited by:Nose geometry.Chipbreaking geometry.
f
Turning applications
Seco Seco Core curriculum of metalcutting -- page page 2626
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Vc must be adapted to the insert gradeand the material of the workpiece.
Vc
Vc = Cutting speed (inch/min)
Turning applications
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Vc = cutting speed (ft/min)
Vc influences:Metal removal rate (productivity).Power consumption.Tool life.
Vc is limited by:Cutting temperature.
Vc
Turning applications
Seco Seco Core curriculum of metalcutting -- page page 2727
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RPM (n) is equal to
Vc x 123.14 x Ø
where Vc is the cutting speed.
n
Turning applications
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Example
Seco Seco Core curriculum of metalcutting -- page page 2828
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Example
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TurningTurning
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