Cutting Technology –chip removing –the largest class of manufacturing activities in engineering production –~1.87 million machine tools –~$168 billion - the total value of the machining operation –numerical control of machine tools –flexible manufacturing

Single point tool operations –turning, boring, planing, and shaping

–the peripheral speed of the workpiece - the cutting speed –the mean value –the depth of cut is –the metal removal rate is b- chip width h- chip thickness fr - feed per revolution

Tool geometry –  - the side cutting edge angle –the tool consists of a cutting insert and a tool holder

The tools

boring tools

classical system

7 - turn a taper 8 - rough turn a tapered thread 9 - finish the thread 10 - drill a short hole 11 - bore the hole to a larger and more accurate diameter 12 - cut an internal groove 13 - cut a short thread in the end of the hole

Automated machine tools –lead, set, clamp, and change tools –control the path of the tool relative to the workpiece –carry out measurements

Drilling operations

–the metal removal rate: d - hole diameter fr - feed rate (feed per revolution) n - rotational speed –the chip area for each edge: ft = fr/2 = feed per tooth –the tangential force in the direction of the cutting speed v is: –the torque is: –the power is: Ks - specific force

Drilling Machines

–the positioning of the spindle relative to the workpiece for the proper location of the hole –if the location is specified to a close tolerance, this cannot be accomplished manually without additional aids

–jig boring machines accurately positioned x, y coordinate motions to drill and bore holes in jigs with precise positions economical for medium size series of workpieces small-lot production on NC drilling machines mass production - use multispindle drilling machines as a part of a transfer line

Multipoint tool operations

–the tooth period: –the mean metal removal rate is: –a r - the radial depth of cut –a a - the axial depth of cut –f - feed rate –the mean power is:

Ways of clamping milling cutters

Broaching –motion: rectilinear –no feed motion –the teeth on the tool are so arranged that they increase in height –the operation is carried out in one pass –suited to mass production of surfaces that are straight in at lease one direction –for machining internal and external surfaces –gears

–the geometry of the broach completely determines the whole operation –the machine supplies one linear cutting motion –pull –push type machine –specialized (workpiece moves while the tool is stationary)