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Terms in this set (55)
Reduce or finish by turning,planing,shape,milling by machine-operated
To cut materials to desired shape& size
The bow drill
Simplest and most likely first machine tool.
The Bow drill
Cord of bow wrapped around round cutting tool. Rotated & produced a hole.
Hand-powered.developed Roman Empire.rotates around the round cutting tool, motion up & down.cutting action to produce holes
Spring pole lathe
Produce cylindrical wooden parts.
Drawback:motion not continuous
Great wheel Lathe
powered by a drive cord or belt attached to large wheel
Great wheel lathe
One person spun wheel to create power,and another performed the machining.
sPring pole drawback; not continuous
Developed water-wheel powered boring maching toto maching the Inside of cannon
Developed a machine that was able to cut screw threads.
Now threaded parts could be produced
Produced first milling machine. this machine tool was able to produce flat surfaces more easily than by hand.
Produces holes by turning a crank by hand. the crank turned gears that rotates the cutting took and advanced it into parts being drilled.
20 century machining
Electric power began to replace steam power,and machine tools continued to become more complex.
Henry ford 1900 creation of assembly line for mass production of automobiles relied on machining.
After World War 2
Great economic growth took place in United States. consumerism began & the machining industry needed to become more efficient to support machining
The invention of Numerical Control(NC) greatly improved machine tool performance. language of machine codes developed and loaded on a punch card or tape then fed to machine tool to automatically guide the motions of the machine and change tools without a operator.
The Nc punch card or tape began to be replaced with computer numerical control (CNc) instead of machine code being punched on the tape or card,code was entered through an integrated computer on machine tool
Final manufactured items used by consumers.
Why do parts need to be produced with such precision?
Performance and interchangeability of parts.
Leading Manufacturing nation in world
The average American worker earned 22.29=46,000 annually on 40 hrs.with benefits included hourly wage under 35$ more then 72,000
Rely on machining and machined parts
Produced from molds. Molds contain cavities that are made to shape of the desired part and then filled with molten plastic.
Tool used to cut or form sheet metal into desired shape
Makes Cans & pans
Form hot pieces of metal into countless products wrenches,hammers,gears
Blanking & piercing die
Punch out sheet metal products using the same principle as a paper hole punch
Require operator to use hand-operated wheels or levers.perform straight line movement
Use multi tooth saw blades to perform cutting.these machines are usually used to cut material to touch lengths quickly in preparations for other machining operation
Use a band-type blade and available in horizontal or vertical machine types
Performs homemaking operations by feeding various types of rotating cutting tools into the work.
Produce cylindrical parts and operates on the principle of moving a cutting tool across the surface of rotating piece of material
Use rotating cutters moved across a part to remove material
Conventional type-accurate homemaking operations and produce flat.
Cnc version cut curves and contours
Grinding wheels in either non precision or precision manner.
Produce very accurate dimensions and very smooth surfaces.
Produces flat surfaces like milling machines but with higher precision
Electrical discharge machining (EDM)
Uses electrical current to machine and conductive material
High tech machining operations are used to produce complex parts
Parts are usually made with one type of die
Electrical discharge machining
Uses electrical current to machine any conductive material that will conduct electricity. No contact is made between the tool & the part but material is eroded away by the spark created.
Classified as CNC machine parts.
Uses high concentrated beam of light with temperature up to 75,000 to cut, groove , or engrave metals
Classified as machine tools and cut very hard materials easily
4 reasons why we need accuracy in machined parts
High accuracy ensures
Water jet machining
Abrasive grit is introduced into a very high-pressure,focused jet of water to perform cutting.
List 4 industries that depend on machining.
Aerospace,automotive,medical fields,plastics,consumable goods
What does abbreviation CNC Stand for
Computer numerical control
What is purpose of drill press?
Performs homemaking operations by feeding various types of rotating cutting tools into the work.it is used when precise hole locations ate not necessary
What machine tool produces cylindrical parts?
Describe purpose of sawing machine?
Used to cut material to rough lengths or to remove large sections of material quickly in prep for other machining operation
What machine tool is available either horizontal or vertical spindle orientation & uses rotating cutting tools to produce flat surface?
Abrasive machining makes use of ___ to remove material?
What does EDM mean?
Electrical discharge machining
What are the 2 types of EDM machine?
Ram or sinker type of EDM-uses an electrode that is opposite of the form desired and is commonly employed is mold making.
Wire-uses a small-diameter wire to produce very intricate shapes and sharp inside corners that could not be machined by other methods.
____uses a high-pressure steam of water containing abrasive particles to cut material
Water jet machining