Production Technology
-VW VW Ao
A1
O Z
-VW
V= VW+VT
N Workpiece
Chip
VT
Cutting tool
X Y
Ao
b=f
N
VT
Absolut velocity
a
VW = f (x, y, z)
VT = f (x, y, z)
Basic condition of cutting
Forces in the material of workpiece and tool makes strain that makes elastic and plastic deformation.
(σ1 ) W ≥ (R m ) W (σ1 )T ≤ (σm )T
HVT ≈ ( 3 ÷ 5 ) ⋅ HVW Main parameters of cutting procedure
V V
Vc=Vy
Chip
Vc=Vy
O Z
VZ
X Y
N N
VX VX
Cutting tool
Workpiece
VZ
N
VW , = VW − VW = 0 VT , = VT − VW = V
V ≅ VC
Calculation of the main cutting velocity 1. By broschure Manufacturer’s brosschure contains cutting parameters (cutting velocity, feed, depht of cut, material workpiece ect.,) In this case the tool life is T=60min. 2. Empiric approaches Kronenberg-method T= 60 min, r =45° for HSS tool
m CV V60, =ε min V A
A=Ao [mm2] .. normal crossection of chip in starting phase
CV [m/perc]….cutting velocity (1.1. table)
εV, ………..experimental data (1.1.table)
1.1. table
TOOL WORKPIECE BRASS BRONZ HSS
εV
1,65 2,23 2,75 500 N/mm2 Rm=500600 N/mm2 Rm=600800 N/mm2
CV
112 80 28,7 50 35 20
ALLOY STEEL Rm=300-
STEEL
2,4
CAST IRON-MILD CAST IRON-MIDDLE
CAST IRON-HARD
3,6
42 26 15
m , V60 = V60 ⋅ ξk ⋅ ξ m min
ξκ modification factort of setting angle of main edge of tool (1.2. table) ξW modification factor that depend of material of cutting edge and workpiece (1.3. table) 1.2. table
Setting angle of main edge of tool modification factor
κ
20
30
40
50
60
70
80
90
κ 1,27 1,17 1,05 0,95 0,86 0,79 0,75 0,74
1.3. table
Material of workpiece STEEL CAST IRON
Carbon tool steel HSS
0,25 0,3 1 1
Carbid cut
4…8 5 and more
Walich-method T= 60 min, r =45° for HSS tool
This equation regarding the HSS tool. This method is more accurate than KRONENBERGmethod. Because this respect not only the normal cross-section of chips but
A1
O Z
-VW
V= VW+VT
N Workpiece
Chip
VT
Cutting tool
X Y
Ao
b=f
N
VT
Absolut velocity
a
VW = f (x, y, z)
VT = f (x, y, z)
Basic condition of cutting
Forces in the material of workpiece and tool makes strain that makes elastic and plastic deformation.
(σ1 ) W ≥ (R m ) W (σ1 )T ≤ (σm )T
HVT ≈ ( 3 ÷ 5 ) ⋅ HVW Main parameters of cutting procedure
V V
Vc=Vy
Chip
Vc=Vy
O Z
VZ
X Y
N N
VX VX
Cutting tool
Workpiece
VZ
N
VW , = VW − VW = 0 VT , = VT − VW = V
V ≅ VC
Calculation of the main cutting velocity 1. By broschure Manufacturer’s brosschure contains cutting parameters (cutting velocity, feed, depht of cut, material workpiece ect.,) In this case the tool life is T=60min. 2. Empiric approaches Kronenberg-method T= 60 min, r =45° for HSS tool
m CV V60, =ε min V A
A=Ao [mm2] .. normal crossection of chip in starting phase
CV [m/perc]….cutting velocity (1.1. table)
εV, ………..experimental data (1.1.table)
1.1. table
TOOL WORKPIECE BRASS BRONZ HSS
εV
1,65 2,23 2,75 500 N/mm2 Rm=500600 N/mm2 Rm=600800 N/mm2
CV
112 80 28,7 50 35 20
ALLOY STEEL Rm=300-
STEEL
2,4
CAST IRON-MILD CAST IRON-MIDDLE
CAST IRON-HARD
3,6
42 26 15
m , V60 = V60 ⋅ ξk ⋅ ξ m min
ξκ modification factort of setting angle of main edge of tool (1.2. table) ξW modification factor that depend of material of cutting edge and workpiece (1.3. table) 1.2. table
Setting angle of main edge of tool modification factor
κ
20
30
40
50
60
70
80
90
κ 1,27 1,17 1,05 0,95 0,86 0,79 0,75 0,74
1.3. table
Material of workpiece STEEL CAST IRON
Carbon tool steel HSS
0,25 0,3 1 1
Carbid cut
4…8 5 and more
Walich-method T= 60 min, r =45° for HSS tool
This equation regarding the HSS tool. This method is more accurate than KRONENBERGmethod. Because this respect not only the normal cross-section of chips but