Lincoln Electric IM366-B Manuale Utente
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steel can usually be easily welded without special pre-
cautions. Some steels, however, contain higher car-
bon levels or other alloys and are more difficult to
weld. Basically, if a magnet sticks to the metal and if
you can easily cut the metal with a file, chances are
good that you will be able to weld the material
with the
SP-100. For further information on identifying various
types of steels and other metals, and for proper proce-
dures for welding them, we again suggest you pur-
chase a copy of “New Lessons in Arc Welding” (see
page 29).
cautions. Some steels, however, contain higher car-
bon levels or other alloys and are more difficult to
weld. Basically, if a magnet sticks to the metal and if
you can easily cut the metal with a file, chances are
good that you will be able to weld the material
with the
SP-100. For further information on identifying various
types of steels and other metals, and for proper proce-
dures for welding them, we again suggest you pur-
chase a copy of “New Lessons in Arc Welding” (see
page 29).
Regardless of the type of metal being welded, it is
important in order to get a quality weld that it be free
of oil, paint, rust or other contaminant's.
important in order to get a quality weld that it be free
of oil, paint, rust or other contaminant's.
TYPES OF WELDS
Five types of welding joints are: Butt Welds, Fillet
Welds, Lap Welds, Edge Welds and Corner Welds.
Welds, Lap Welds, Edge Welds and Corner Welds.
Of these, the Butt Weld and Fillet Weld are the two
most common welds.
most common welds.
WELDING PROCEDURES
Butt Welds
Place two plates side by side, leaving a space approx-
imately one half the thickness of the metal between
them in order to get deeper penetration.
imately one half the thickness of the metal between
them in order to get deeper penetration.
Securely clamp or tack weld the plates at both ends,
otherwise the heat will cause the plates to move apart
(see drawing):
otherwise the heat will cause the plates to move apart
(see drawing):
Now weld the two plates together. Weld from left to
right (if right handed). Point the wire electrode down in
the crack between the two plates, keeping the gun
slightly tilted in the direction of travel.
right (if right handed). Point the wire electrode down in
the crack between the two plates, keeping the gun
slightly tilted in the direction of travel.
Watch the molten metal to be sure it distributes itself
evenly on both edges and in between the plates.
evenly on both edges and in between the plates.
Penetration
Unless a weld penetrates close to 100% of the metal
thickness, a butt weld will be weaker than the material
welded together. In this example, the total weld is only
half the thickness of the material; thus the weld is only
approximately half as strong as the metal.
thickness, a butt weld will be weaker than the material
welded together. In this example, the total weld is only
half the thickness of the material; thus the weld is only
approximately half as strong as the metal.
In this example, the joint has been welded so that
100% penetration could be achieved. The weld, if
properly made, is as strong as or stronger than the
original metal.
100% penetration could be achieved. The weld, if
properly made, is as strong as or stronger than the
original metal.
Fillet Welds
When welding fillet welds, it is very important to hold
the wire electrode at a 45° angle between the two
sides, or the metal will not distribute itself evenly. The
gun nozzle is generally formed at an angle to facilitate
this.
the wire electrode at a 45° angle between the two
sides, or the metal will not distribute itself evenly. The
gun nozzle is generally formed at an angle to facilitate
this.
WELDING IN THE VERTICAL POSITION
Welding in the vertical position can be done either ver-
tical-up or vertical-down. Vertical-up is used whenever
a larger, stronger weld is desired. Vertical-down is
used primarily on sheet metal 5/32" (3.9 mm) and
under for fast, low penetrating welds.
tical-up or vertical-down. Vertical-up is used whenever
a larger, stronger weld is desired. Vertical-down is
used primarily on sheet metal 5/32" (3.9 mm) and
under for fast, low penetrating welds.
Use of the SP-100 on thicker materials than rec-
ommended may result in poor welds. The welds
may “look” good, but may just be “sitting” on top
of the plate. This is called “Cold Casting” and will
result in weld failure. See Recommended Processes
and Equipment.
ommended may result in poor welds. The welds
may “look” good, but may just be “sitting” on top
of the plate. This is called “Cold Casting” and will
result in weld failure. See Recommended Processes
and Equipment.
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Poor
Butt weld
Lap weld
Edge weld
Fillet weld
Corner weld
Good
45˚
WARNING