What are the three stages of the manufacturing process?
Primary shaping, secondary processing, post processing
What are the primary shaping methods?
casting methods
molding methods
deformation methods
additive manufature
What are the two casting methods?
sand casting and die casting
describe sand casting
place mould pattern in sand
set up the gating system with pouring basin to allow metal to flow
remove mould pattern to create mould cavity
pour molten metal into pouring basin to fill the mould cavity
wait for metal to cool
break open mould to remove metal casting
describe die casting
attach die to the machine
inject molten metal into the die under high pressure through the plunger
die is immersed or sprayed in water to quicken cooling
once cooled, die is opened
List advantages and disadvantages of die casting
good for mass production
great precision
good surface finish
limited to low melting point metals
high expense
can’t handle larger parts well
List advantages and disadvantages of sand casting
mould is cheap to produce
lead time is short
can create complex shapes
parts produced are often crude
surface finish issues
describe injection moulding
prepare mould with lubricant for aid in removal
add plastic into hopper
plastic is melted and moved along the barrel via the screw
mould is cooled before ejection
List advantages and disadvantages of injection moulding
efficient cost
good for mass production
high quality
high inital cost
high setup time
environmentally unfriendly
describe rolling
slabs are heated to extremely high temp
slab is cleaned to remove millscale
slab goes through multiple rolling mills that reduces it’s thickness
slab is cooled
slab is then coiled onto a coil
List advantages and disadvantages of rolling
good for mass production
cost effect for maintenance
consistency in quality
high initial setup cost
limited complexity
describe extrusion
raw material is fed into a hopper
tmaterial drops into abarrel, where a rotating screw pushes it forward
heating elements melt the material
the material drops into the extruder’s barrel, where a rotating screw pushes it forward
What’s the difference between hot and cold extrusion?
hot extrusion takes place above crystallization temp while cold extrusion takes place below
List advantages and disadvantages of hot extrusion
low force requires as material is easier to work in hot form
no strain hardening
low quality surface finish
high maintenance required
List advantages and disadvantages of cold extrusion
High mechanical properties.
High quality surface finish
High force required to shape the metal.
Metal will strain harden.
Describe vacuum forming
polymer sheet is heated until it is soft
draped over a mold
a vacuum is applied which pulls the polymover over the mould
the sheet is then ejected from the mould
List advantages and disadvantages of vacuum forming
low cost
great for large parts
limited depth/thickness for parts
limited production speed
Give examples of additive manufacturing (3D printing)
direct metal deposition
wire filament
uv curving
poweder bed sintering
List advantages and disadvantages of additive manufacturing
user friendly
can create complex shapes
great for small batch production
little waste
high entry cost
materials don’t have same properties as other counterparts
surface finish can be rough
slow compared to other methods
Give examples of secondary processes
CNC machining
Turning
water jet cutting
Metal sheet bending
What are the two types of post processing?
joining and surface treatment
Which manufacturing methods work with metals?
sand casting
die casting
rolling
extrusion
3D printing/additive manufacturing
Which manufacturing methods work with plastics?
injection moulding
rolling
extrusion
vacuum forming
additive manufacturing
What is single point cutting?
a tool with one main cutting edge to remove material
