Metal processes Flashcards
List the 7 metal forming processes
press forming spinning cupping and deep drawing drop forging wrought iron forging bending rolling
List the 6 metal distribution processes
sand casting gravity die casting pressure die casting (hot chamber) pressure die casting (cold chamber) investment casting low temperature pewter casting
List the 7 metal addition processes
MIG welding TIG welding Oxy-acetylene welding Spot welding Soldering Brazing Riveting and pop riveting
What is metal forming?
processes in which no material is removed, but materials are deformed o produce required shapes
What is metal redistribution?
processes where material is changed from one form to another without loss o material
What is metal wastage?
processes that cut away material to leave the desired shape
Describe press forming
shapes sheet metal into 3D forms
suitable for mass production
e.g. metal seats, car body panels
Describe spinning
product may show parallel lines where sheet has been forced into mandrel
suitable for mass p
e.g. saucepan, kettles
Describe cupping and deep drawing
starts with metal blank metal is stretched into shape high initial tooling cost mass p e.g. tube like shapes
Describe drop forging
used for products that need to be tough and hard
uses billet stock form
hot metal billet shaped on an anvil or die and then pressed Ito shape and cooled
e.g. spanner, pliers
Describe wrought iron forging
uses bar stock form uses wrought iron (low carbon content) can be hand or hydraulic press processes suitable for one off p e.g. decorative metalwork such as fencing
Describe bending
does not include and punching or trimming
large scale
e.g. seams on metal edges, bending sheets for product casings
Describe rolling
hot rolling metal results in uniform mechanical properties
surface usually coated with carbon deposits
e.g. beams, channels railway tracks
cold rolling results in tighter tolerance and better surface finish surface
e.g. filing cabinets, steel drums
Describe sand casting
labour intensive
not high quality surface finish
one off
e.g. railway carriage wheels, bollards
Describe gravity die casting
relies on gravity to help the metal flow into the mould
used for thicker mud sections
mass p
alloy wheels, engines
Describe pressure die casting hot chamber
molten metal stored in chamber then shot of molten metal is forced into the die
fast
e.g. decorative door knobs, toy cars
Describe pressure die casting cold chamber
molten metal ladled into shot chamber and hydraulically pushed into chamber
e.g. decorative door knobs, toy cars
True or false : all the die casting processes use lower melt point metals such as aluminium and some alloys
TRUE
Describe investment casting
used for intricate shapes
high quality excellent finish
e.g. cast jewellery , hip replacements
Describe low temperature pewter casting
used for school projects
MDF moulds
e.g. jewellery, key fobs
Describe MIG welding
uses electrode wire and inert gas
suitable for this gauge metals
e.g. tubular products
Describe TIG welding
uses filler rod and inert gas
accurate strong weld but require high skill and time
e.g. stainless steel ladders for boats or swimming pools
Describe Oxy-acetylene welding
uses steel filler rod
useful for quick repair jobs
no electricity needed
e.g. used to weld mild steel sheet
Describe spot welding
sheet held between two copper electrodes that form weld when the charged electrodes are contact with the metal
e.g. weld mild steel sheet metal at points along a length
