CNC Turning and programming and cnc milling 2.ppt

Non

6. Answer to the above is NC System

13. Block
Block No.
Words End of Block
G 00
Address
Data

14. Header
Body
End

16. 0,0

21. Writing Format
G71 U1.0 R1.0;
G71 P10 Q20 U0.5 W 0.5 F0.25;
N10 G00 X…..;
…….
…….
…….
N20 ……..;
G70 P10 Q20 F0.15;
1
st
Line of G71:
U –Specifies the depth of cut in each pass
R –Retract amount after every pass
2
nd
Line of G71:
P –Specifies the start block number
Q –Specifies the end block number
U –Specifies the finishing allowance in X
W –Specifies the finishing allowance in Z
G70 –Finishing Pass

22. ……
N10 G00 X38.0 Z2.0;
N20 G71 U1.5 R0.5;
N30 G71 P40 Q130 U0.5 W0.2 F0.35;
N40 G01 X17.0;
N50 G01 Z0.5;
N60 G01 X20.0 Z-1.5;
N70 G01 Z-30.0;
N80 G1 X 25.0;
N90 G03 X25.0 Z-31.0 R1.0;
N100 G01 X30.0 Z-65.0;
N110 G01 Z-74.0;
N120 G02 X36.0 Z-77.0 R3.0;
N130 G01 X38.5;
N140 G70 P40 Q 130;
….

24. 1.Movement Instruction
•G00, G01, G02, G03
2.Machine Instruction
•M00, M02, M03, M04, M05, M06, M08, M09, M30
3.Tool Instruction
•T0101
4.Technological Instruction
•Cutting Speed
•Spindle Speed
•Feed
5.Dimensional Instruction
•Metric
•Inch

27. Writing Format
G72 W1.0 R1.0;
G72 P10 Q20 U0.5 W 0.5 F0.25;
N10 G00 z…..;
…….
…….
N20 ……..;
G70 P10 Q20 F0.15;
1
st
Line of G72:
W –Specifies the depth of cut in each pass
(in Z Direction)
R –Retract amount after every pass
2
nd
Line of G72:
P –Specifies the start block number
Q –Specifies the end block number
U –Specifies the finishing allowance in X
W –Specifies the finishing allowance in Z
G70 –Finishing Pass

31. Groups of G-Codes
Group ‘0’: G04, G10, G27, G28, G29, G30, G31
G50, G65, G72, G73, G74, G75, G76
Group ‘1’: G00, G01, G02, G03, G90, G92, G94
Group ‘2’: G66, G67, G96, G97
Group ‘4’: G70, G71
Group ‘6’: G20, G21
Group ‘7’: G40, G41, G42
Group ’11’: G98, G99

33. R = Retraction amount after every depth
Z = TOTAL Depth
Q = Peck Increment (in micron)
F = Feed Rate

40. G73 1
ST
Line:
U : Specifies Roughing Material on X-Axis (in Radius)
W: Specifies Roughing Material in Z-Axis
R: Number of Passes.
G73 2nd Line:
U : Specifies Finishing Allowance on X-Axis
W: Specifies Finishing Allowance on Z-Axis
P & Q: Start & End Block Number Respectively

50. Crest
Root

51. Calculation for Thread Height:
h = 0.61343 x pitch
Core Diameter, d= D –2x h

54. 1
ST
LineofG76:
Pxxyyzz:
xx:No.finishingPasses
yy:Chamferingamountattheendofthread
zz:Angleoftooltip(indeg)
Q….:Minimumdepthofcutineachpass(inmicron)
R….:Finishingallowance(inmm)
2
nd
LineofG76:
X…..:Corediameterofthread(mm)
Z….:Lengthofthread(mm)
P….:Heightofthread(inmicron)
Q…..:Depthofcutinfirstpass(inmicron)
F…..:Pitchofthread(inmm)

57. Sub Program

59. Programmed Path
Actual Path Generated
(Material Left on Tool Path)

61. G42 (RIGHT)
G41 (LEFT)

62. Radius of Tool Nose

63. 4
5
6
2
7
3 8
1

67. Sl X-offsetZ-offsetR T
1 ……….. ……….. 0.8 3

69. G00 Rapid Linear MovementG00 X…. Z…. Used for air
movements only
G01 Linear Interpolation with
Program defined feed
G01 X …. Z …. F….Used for metal
cutting
G02 Circular Interpolation
Clock Wise (CW) Direction
G02 X… Z... R… F…Used for metal
cutting
G03 Circular Interpolation
Counter Clock Wise
(CCW) Direction
G03 X… Z... R… F…Used for metal
cutting