AIT Flashcards
Smaw fillet welds on mild steel
Hot pass is a first fill
.
Electrode angle =
Half the included angle
Another term for inclination is
Work angle
Smaw electode inclination
Flat and overhead
. 5-15
Forehand
Flatter wider smoother metal flow less pen
Backhand
Deeper pen narrow bead more build up
Inclination for vertical
0-10 forehand
6010
DCRP - reverse polarity
DCEP
Weave bead should not exceed
2-3 times electrode diameter
The herringbone variation eliminates
Undercut
Weave techniques
Herringbone
Crescent weave
Lazy L
Sawtooth weave
Groove welds must be reinforced at the center of the weld at least….
1.6 (1/16) for material buildup
10 percent material thickness
E4310 (E6010)
1/8
Current type
Polarity
Amps
DCEP
DCRP reverse polarity
80-140
E4918 (E7018)
3/33
Currently
Polarity
Amps
AC DC
DCEP
DCRP
70-120
E4918 (E7018)
1/8
Current
Polarity
Amps
AC DC
DCEP
DCRP
80 - 175
Electrode starting methods
Scratch
Tapping
Good polarity checking rod
6010 bc it only works on DCRP
Electrode with added potassium
6011 has added potassium to stabilize the arc for AC welding
25.4 mm = 1”
F system
F1. F2. F3. F4.
F1 : iron
F2 : Rutile
F3 : Cellulose
F4 : Lime
Hermetically sealed rods
Temp
Re- bake temp
7018 - prevent moisture build up
50 - 250 F
Re-bake
500 - 800F
6010 moisture content
3-7 percent
7018 polarity
AC or DCRP
Short arc in Smaw
Penetration
Amps and volts
High amps low bolts
High narrow deep pen
Long arc in Smaw
Penetration
Amps and bolts
Low amps high volts
More fluid puddle, blends better
Less pen
Starting arc volts
50-100 amps
Maintaining an arc
17-40
Electromotive force EMF
Voltage
Blow machine out with
High volume
Low pressure air
Percentages of carbon and what they make
Low - .05-.30
Nails
Mild .15-.30
General fab
Med .30-.45
Preheat needed, engine connecting rods
High .45-.75
Preheat and post head, springs, crankshafts
Very high .75-1.5
Files
Cast iron 2-4.5
CSA and ASTM
Structural steel plates and shapes
AISI
Steel sheet stock
SAE and AISI
Steel bar stock
CSA system
AT
Atmospheric corrosion resistant weldable notch tough