Cornwell Tools MIG 250MGS, Руководство пользователя

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VERTICAL POSITION It is easier for many people to Pull the torch from top to bottom. It can be
difficult to prevent the puddle from running downward. Pushing the torch from bottom to top may
provide better puddle control and allow slower rates of travel speed to achieve deeper penetration.
When vertical welding, angle B (see HOLDING THE TORCH) is usually always kept at zero, but
angle A will generally range from 45 to 60 degrees to provide better puddle control.
OVERHEAD POSITION Is the most difficult welding position. Angle A (see HOLDING THE TORCH)
should be maintained at 60 degrees. Maintaining this angle will reduce the chances of molten metal
falling into the nozzle. Angle B should be held at zero degrees so that the wire is aiming directly into
the weld joint. If you experience excessive dripping of the weld puddle, select a lower heat setting.
Also, the weave bead tends to work better than the stringer.
8.4 Multiple pass welding
Butt Weld Joints When butt welding thicker materials, you will need to prepare the edges of the
material to be joined by grinding a bevel on the edge of one or both pieces of the metal being joined.
When this is done, a “
V”
is created between the two pieces of metal, that will have to be welded
closed. In most cases more than one pass or bead will need to be laid into the joint to close the “ V”
.
Laying more than one bead into the same weld joint is known as a multiple-pass weld.
The illustrations in following figure show the sequence for laying multiple pass beads into a single
“V” butt joint.