Everlast POWER MTS 221STi, Руководство оператора

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MIG OPERATION
DOUBLE J - GROOVE
V - GROOVE (60 - 80
°)
DOUBLE V - GROOVE
DOUBLE U - GROOVE
U - GROOVE
BEVEL GROOVE DOUBLE BEVEL GROOVE
J - GROOVE
JOINT PREPARATION
Besides a butt joint and lap joint which are often used
for thinner metal gauges, consider using one of these
groove joints for best welding results. When grinding
or cutting the bevels, especially with a single V -
groove, it may be beneficial to leave a small land with
a gap between the joint to achieve full penetration. In
this case a temporary backer plate can be used to
support the bottom of the weld to create the root pass.
The root weld will weld the backer to the main plate.
This backer can later be ground or cut off. However,
in many cases a plain open root can be used as a
backer plate adds to the time and labor involved. A
knife edge is also acceptable so long as the joint is
fully penetrated when the weld is completed. Open
root gaps without a backer can range from 1/16” to
1/8” depending upon wire diameter and application.
≥ 1/4” Fillet ≥ 1/4” Fillet
s
≥ 1/4” V Joint
≥ 1/4” Butt Joint
When welding material 1/4” and over be careful about trying to put too much metal down in
a single pass. Use multiple passes to complete the weld along with any necessary joint prep-
aration especially with wires of smaller diameter. As metal thickness goes up so does the
number of required passes. Depending upon the wire diameter and power settings used, a
1/4” joint may only require 1 or 2 passes, but a 3/8” joint in plate metal or pipe will require
not only beveling but 4 to 6 overlapping weld passes including a cap and root pass.
Basic Theory and Function
Section 3