Transcript Arc Furnace Melting and Sand Casting of Aluminum and Copper James Bonnell

Arc Furnace Melting and
Sand Casting of Aluminum
and Copper
James Bonnell
James O’Brien
Engr 45
Dec 8, 2004
Arc Furnace Typical Uses
•
•
•
•
Metal Recycling
Used to reclaim iron, nickel and cobalt alloy
Scrap is generally 100% of the charge
With computer control is used to separate
various mixed scrap to specific compositions
Arc Furnace
Benefits:
• Cost per ton of final product is less
(taking into account all expendables)
•
•
Can melt almost any type of metallic scrap
Good for smaller production runs requiring
less capacity.
Source: http://tristate.apogee.net/et/
Power Consumption
Energy Required to Produce One Ton of
Liquid Steel
20
18
Million Btu
16
14
12
10
8
6
4
2
0
Arc Furnace
Oxygen Furnace
Process
Source: http://tristate.apogee.net/et/
Cost Per Ton of Steel
Material Cost per Ton of Produced
Steel
140
Dollars per Ton
120
100
80
60
40
20
0
Arc Furnace
Blast Furnace
Process
Source: http://tristate.apogee.net/et/
Basic Electric Arc Furnace
DC Electric Arc Furnace
www.jfe-21st-cf.or.jp
Current Carrying Capacity
Nominal Diameter
Electrode Type
mm
inch
Regular Power
75
3
1,000 ~ 1,400
100
4
1,500 ~ 2,400
150
6
3,000 ~ 4,500
200
8
5,000 ~ 6,900
5,400 ~ 9,000
250
10
7,000 ~ 10,000
8,000 ~ 12,000
300
12
10,000 ~ 13,000
13,000 ~ 17,400
18,000 ~ 22,000
350
14
13,500 ~ 18,000
17,400 ~ 24,000
20,000 ~ 30,000
400
16
18,000 ~ 23,500
21,000 ~ 31,000
25,000 ~ 40,000
450
18
22,000 ~ 27,000
25,000 ~ 40,000
32,000 ~ 45,000
500
20
25,000 ~ 32,000
30,000 ~ 48,000
38,000 ~ 55,000
Source: www.foundrytraders.com
High Power
Ultra High Power
Our Arc Furnace
•
Started as a
standard arc lamp
used for exposing
photographic
emulsions.
Modified Arc Lamp
•
•
Moved the bottom
electrode to be
parallel with the top
electrode
Added:
•
•
Platform
Crucible
Attempted Arc Start with Steel
Arc Start with Carbon Rod
Sand Casting Mold and
Products
www.birt1.demon.co.uk
www.simmons.com
Sand Casting Suitability
Advantages:
Disadvantages:
Least Expensive Casting
Process
Can Only Cast Basic Part Shape
Castings can be up to Several
Tons
Less Expensive than
Machining Shapes from Bar
Stock
Castings Require Secondary
Machining
Rough Surface Finish
Can Cast Intricate Shapes
Can be Used with Most
Pourable Metals and Alloys
www.casting-source.com
Casting Sand Types
•
•
•
Basic casting sand consists of bentonite
clay and sand (usually 120 grit)
Chromite sand: a high quality refractory
molding sand,with high chilling effect and
stability
Zircon sand: particularly suitable for higher
melting point alloys
Source: http://www.foundrytraders.com
Basic Tools
Shrinkage Consideration
Shrinkage Rate for Small Castings
Iron - 1/8" per foot
Steel - 1/4" per foot
Aluminum - 5/32" per foot
Brass - 3/16" per foot
www.casting-source.com
General Setup
www.lethbridgeironworks.com
Our setup and mold
Disappointing Results
•
•
•
Insufficient input heat
to maintain molten
state
Worked to melt small
samples
Crucible broke from
thermal shock when
the sample melted
Final Castings
•
•
Used Oxyacetylene
Torch to heat steel
crucible that would not
suffer thermal shock.
Cast aluminum and
copper alloys (not quite
enough heat input for
copper)
Original