CNC MACHINE
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Transcript of CNC MACHINE
1955 - US Air Force define a need to develop a machine tool capable of machining complex and close tolerance aircraft parts.
1959 - MIT is the contractor and builds the machine for the project. MIT announces Automatic Programmed Tools (APT) programming language
1960 - Direct Numerical Control (DNC). This eliminates paper tape and allows programmers to send files directly to machine tools
1980’s - CNC machine is introduced. Unix and PC based systems
1997 - PC- Windows operating system is attached to cnc
Turning Centers
Milling Centers
Vertical Machining Centers
Horizontal Machining Centers
Drilling Machines
EDM Machines
Laser-Cutting Machines
Spindle in a vertical orientation.
VMCs are high-precision
Used for tight-tolerance
Spindle in a horizontal orientation.
Horizontal orientation encourages
chips to fall away.
HMCs are high-precision
Used for tight-tolerance
Controlled by G and M codes.
These are number values and co-ordinates.
Each number or code is assigned to a particular operation.
Typed in manually to CAD by machine operators.
G & M codes are automatically generated by the computer software.
O - Program number N - Sequence number G - Preparatory function X - X axis designation Y - Y axis designation Z - Z axis designation R - Radius designation F – Feed rate designation S - Spindle speed designation H - Tool length offset designation D - Tool radius offset designation T - Tool Designation M - Miscellaneous function
G00 Rapid Transverse G01 Linear Interpolation G02 Circular Interpolation, CW G03 Circular Interpolation, CCW G20/G70 Inch units G8 Cancel canned cycles G81 Drilling cycle G82 Counter boring cycle G83 Deep hole drilling cycle G90 Absolute positioning G91 Incremental positioning
M00 Program stop M01 Optional program stop M02 Program end M03 Spindle on clockwise M04 Spindle on counterclockwise M05 Spindle stop M06 Tool change M08 Coolant on M09 Coolant off M10 Clamps on M11 Clamps off M30 Program stop, reset to start
Automobile Part
Aerospace
CNC machine manufactures this items
Diamond & Jewellery Ind.
Textile Machinery
Die & Mould Manufactures
• Posess hardness and strength at high temperatures
• Able to withstand when heat is generate
• Angle of the cutting face
• Flute width, number of flutes, teeth, and margin size
Lubricating during cutting process
Cooling the workpiece at high cutting speeds
Improving tool life,
Improving surface finish
Flushing away chips from the cutting zone
Corrosion protection of the machined surface
STRAIGHT OILS -Non-emulsifiable and are used in machining operations in an undiluted form they are composed of a petroleum oil , lubricants such as fats, vegetable oils
( BEST LUBRICATION )
SOLUBLE OILS -Contain no petroleum or mineral oil , composed of alkaline inorganic and organic compounds ( BEST COOLING )
SEMISYNTHETIC FLUIDS- Emulsion when mixed with water
( LEAST EXPENSIVE )
SYNTHETIC FLUIDS-Combination of synthetic and soluble oil fluids
( COST AND HEAT TRANSFER PERFORMANCE )
High Accuracy e.g. Aircraft parts
Production rate is very high
Complex surfaces need to be machined
Flexibility in job change , automatic tool settings
More safe , higher productivity , better quality
Less paper work , faster prototype production
Costly setup
Skilled operators
Computers , Programming knowledge required
Maintenance is very difficult
.