DMFD 3333

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DMFD 3333 CNC TECHNOLOGY
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DMFD 3333 CNC TECHNOLOGY
PROCESS PLANNING/ PROGRAMMING PROCEDURE
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DMFD 3333 CNC TECHNOLOGY

• GOAL
• - Completion of all instruction in the form of a
  program that will result in an error free, safe
  and efficient CNC machining.

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DMFD 3333 CNC TECHNOLOGY

• All planning must be approached in a logical way
  and methodical way
• Decision What task to be done?
• What goals?

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DMFD 3333 CNC TECHNOLOGY

• PROCESS
• Study of initial information (drawings)
• Material evaluation
• Machine tool selection
• Sequence of machining operation
• Tooling selection and arrangement of cutting tool
• Setup parts
• Technological data
• Determination of tool path
• Program writing and preparation to transfer to
  CNC
• Program testing and debugging
• Program documentation

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DMFD 3333 CNC TECHNOLOGY

• PROCESS
• Study of initial information (drawings)
• Material evaluation
• Machine tool selection
• Sequence of machining operation
• Tooling selection and arrangement of cutting tool
• Setup parts
• Technological data
• Determination of tool path
• Program writing and preparation to transfer to
  CNC
• Program testing and debugging
• Program documentation

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DMFD 3333 CNC TECHNOLOGY

• Study of Information (Drawings)
• Very important document where it physically
  visual the shape, dimensions, tolerances, surface
  finish and many other requirements such as number
  of parts and other secondary processes

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DMFD 3333 CNC TECHNOLOGY

• Material Evaluation
• Typical material is raw and unmachined billet,
  bar, plate, forging, casting etc
• The size and shapes of the the material determine
  the type of fixturing
• Machinability charts for recommeded speed and
  feed for most common material

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DMFD 3333 CNC TECHNOLOGY

• Machining Sequence
• Order of machining sequence.
• Technical Skill and and machine shop experience
  is important.
• The machining sequence must be in logical order.
• Determine the shape of the part.

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DMFD 3333 CNC TECHNOLOGY

• Machining Sequence
• Order of machining sequence.
• Technical Skill and and machine shop experience
  is important.
• The machining sequence must be in logical order.
• Determine the shape of the part.

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DMFD 3333 CNC TECHNOLOGY

• Work Holding Devices

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DMFD 3333 CNC TECHNOLOGY

• The method of holding the parts to be machine on
  the machine so that
• Parts is correctly orientated
• Dimension is not distorted
• Locate part with respect to its datum
• Proper locating and clamping ensures repeated
  products and accuracy.

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DMFD 3333 CNC TECHNOLOGY

• Work Holding devices for milling
• Vice
• Angle plate
• Direct clamping or fixtures
• Chuck
• Tomb stones

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DMFD 3333 CNC TECHNOLOGY

• VICE
• Most commonly used for simple shape machining
• Manually, air or hydraulically operated
• Mount on table so that it is parallel to its x
  and y axis
• Movable jaw should not be used as a datum as it
  moves

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DMFD 3333 CNC TECHNOLOGY

• ANGLE PLATE
• For work that need to be held at 90o angle to the
  axis
• L shaped cast iron or steel that has tapped
  holes or slots to provide for clamping purposes
• Suitable for horizontal machining centre

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DMFD 3333 CNC TECHNOLOGY

• CHUCK
• Three jaw chuck used to hold cylindrical
  workpiece on machine table

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DMFD 3333 CNC TECHNOLOGY

• DIRECT WORK MOUNTING
• Used to hold big or having odd shaped workpieces
• Bolted directly to the table
• Required ingenuity and expertise

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DMFD 3333 CNC TECHNOLOGY

• FIXTURES
• Used in the following cases
• The stock require some periphery machining
• The stock is too large to be held by a machine
  vice
• Not rectangular in shape.

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DMFD 3333 CNC TECHNOLOGY

• TOMB STONE
• Allow multipart to be held on any or all of its
  parts.
• Manual or power clamping can be used
• Held on rotating machine pallets so that each
  side could be represented.
• Increase productivity.

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DMFD 3333 CNC TECHNOLOGY

• MILLING PROGRAMMING

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DMFD 3333 CNC TECHNOLOGY

• TYPICAL PROGRAM
• O002 Program No
• N1 G20 Unit setting in different block
• N2 G17 G40 G80 G49 Initial Setting and
  cancellation
• N3 T01 Tool 1 in waiting position
• N4 M06 Tool 1 into spindle
• N5 G90 G54 G00 X.. Y Z.. M3 TO2 T01 restart
  block T02 into waiting position
• N6 G43 Z2.0 H01 M08 Tool lgth offset coolant on
• N7 G01 Z F Feed to Z depth
• (.Cutting tool motion with tool 1)

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DMFD 3333 CNC TECHNOLOGY

• N33 G00 G80 Z2.0 M09 Clear above part coolant
  off
• N34 G28 Z2.0 M05 Home in Z only coolant off
• N35 M01 Optional stop
• ----
• N36 T02 Tool 2 in waiting
• N37 M06 Tool 2 in spindle
• N38 G90 G54 G00 X..Y.. S.. M03 TO3 T02 start
  block T03 in waiting
• N39 G43 Z2.0 H02 M08 Tool lgth offsett coolant on
• (N40 G43 G01 Z-F..) Feed to Z depth
• .Cutting motion with tool 2

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DMFD 3333 CNC TECHNOLOGY

• N62 G00 G80 Z2.0 M09
• N63 G28 Z2.0 M05
• N64 M01
• .
• N65 T03
• N66 M06
• N67 G90 G54 G00 X.. Y.. S..M03 T01
• N68 G43 z2.0 H03 M08
• (N69 G01 Z-F..
• ..Cutting motion with tool 3

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DMFD 3333 CNC TECHNOLOGY

• N86 G00 G80 Z2.0 M09
• N87 G28 Z2.0 M05
• N88 G28 X.. Y..
• N89 M30

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DMFD 3333 CNC TECHNOLOGY

• Preparatory Command
• Identify as G codes
• To preset or to prepare the control system to a
  certain desired condition or to a certain mode or
  state of operation

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DMFD 3333 CNC TECHNOLOGY

• Description and Purpose
• e.g. N7 X200 Y10 end position of the cutting
  tool does not show coordinates are absolute or
  incremental, imperial or metric, rapid or feed
  hence the block is in complete

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DMFD 3333 CNC TECHNOLOGY

• Example A
• N7 G90 X13 Y10
• Example B
• N3 G90
• N4 .
• N5..
• N6..
• N7 G00 X13.0 Y10.0

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DMFD 3333 CNC TECHNOLOGY

• EXAMPLE C
• N3 G90 G00
• N4
• N5
• N6 ...
• N7 X13.0 Y10.0
• EXAMPLE D
• N2 G90
• N3 G00
• N4 ..
• N5 .
• N6 .
• N7 X13.0 Y 10.00

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DMFD 3333 CNC TECHNOLOGY

• Will there be any difference in motion in all the
  example ?

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DMFD 3333 CNC TECHNOLOGY

• NO there is no change in G codes between block
  N4 and N6
• One G codes in a modal will replace another g
  code from the same group

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DMFD 3333 CNC TECHNOLOGY

• G CODES IN A BLOCK
• Several preparatory function may be used in a
  single block, providing they are not in a logical
  conflict with each other

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DMFD 3333 CNC TECHNOLOGY

• Modality of G command
• N3 G90 G00
• N4 X0
• N5 Y20
• N6 X15 Y22
• N7 X13.0 Y10.0

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DMFD 3333 CNC TECHNOLOGY

• For a command to be a modal, it means it has to
  remain in a certain mode until cancel by another
  mode

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DMFD 3333 CNC TECHNOLOGY

• Conflicting command in a block
• It is impossible to have rapid motion and a
  cutting motion in one block e.g G00 and G01
• - The latter will be used if accidentally used

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DMFD 3333 CNC TECHNOLOGY

• Word Order in block
• G codes are normally programmed at the beginning
  of a block
• e.g. N40 G91 G01 Z-1 F200

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DMFD 3333 CNC TECHNOLOGY

• GROUPING OF COMMAND
• Commands cannot be in the same block G00, G01,
  G02, G03
• Any G code from a given group automatically
  replaces another G code from the same group

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DMFD 3333 CNC TECHNOLOGY
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DMFD 3333 CNC TECHNOLOGY

• MICELLANEOUS FUNCTION

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DMFD 3333 CNC TECHNOLOGY

• M code Miscellaneous function
• - machine function (not all)

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DMFD 3333 CNC TECHNOLOGY

• Machine Related Function
• Spindle rotation CW or CCW
• Gear range change Low/medium/high
• Automatic tool change ATC
• Automatic Pallet change APC
• Coolant operation ON or OFF
• Tailstock or Quill motion IN or OUT

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DMFD 3333 CNC TECHNOLOGY

• PROGRAM RELATED FUNCTION
• Control of machine function
• Control of the program function

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DMFD 3333 CNC TECHNOLOGY

• SPECIAL MDI FUNCTION
• Manual Data Input (MDI) used to program from
  the controller simple and repetitive process. M
  funcion cannot be programmed.

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DMFD 3333 CNC TECHNOLOGY

• M FUNCTION IN A BLOCK
• Only ONE function in a block
• Each M function is designed logically also
  common sense

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DMFD 3333 CNC TECHNOLOGY

• START OF BLOCK
• M03 Spindle rotation normal
• M04 Spindle rotation reverse
• M06 ATC
• M07 Coolant mist
• M08 Coolant ON

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DMFD 3333 CNC TECHNOLOGY

• END OF BLOCK
• M00 Compulsory program stop
• M01 Optional Stop
• M02 End of program
• M05 Spindle stop
• M09 Coolant OFF
• M30 Program end
• M60 APC

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DMFD 3333 CNC TECHNOLOGY

• MACHINE FUNCTION
• Coolant Function M07, M08, M09
• Spindle Function M03, M04, M05
• Gear range Selection M41, M42, M43, M44
• Machine Accessories M06, M60, M23.m24, M98, M99

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DMFD 3333 CNC TECHNOLOGY

• THANK YOU