Metal Machining Flashcards
Operations/Tools do we associate with Machining
Turning
Drilling
Milling
advantages of Machining
- All Metals can be machined
- A variety of parts and shapes are possible
- good dimensional accuracy and good surface finish
Disadvantages of machining
- wasteful of material such as chips
- time-consuming
The affects of high temperature to the machining process
- reduce tool life
- produce hot ships that might be dangerous to the operator
- can cause inaccuracies in part dimensions due to thermal expansion of work material
difference between turning and boring
- Boring is performed on the inside diameter of an existing hole to enlarge it
- turning is performed on the outside
advantages of broaching
- good surface finish
- good tolerances
- a variety of work shapes possible
what is sawing
cuts a narrow slit in work by consisting of a series of narrowly spaced teeth and typically cut off unwanted parts or separate work part into two pieces
reasons why machining may be required
- close tolerances
- good surface finish
- accurate thread holes and thread depths
Types of chip machining
- discontinuous chip
- continuous chip
- continuous chip with built-up edge
- serrated chip
the equation for chip removal rate
removal rate = cutting speed x feed x depth of cut
equation of chip thickness ratio
chip thickness = thickness of chip prior to chip formation / chip thickness after separation
eqaution for shear plane angle
tan (theta) = rcos(rake angle) / 1-(chip ratio)*sin(theta)
how is surface roughness in machining determined
- geometric factors of the operation
- work material factors
- vibration and tool factors
the equation for deal surface roughness
surface roughness = feed^2/32 *nose radius
