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4.
GENERAL WELDING INFORMATION
4.1
PREPARATIONS FOR WELDING
an important factor in making a satisfactory weld is preparation.
This includes studying the process and equipment and then practice
welding before attempting to weld finished product. An organized, safe,
convenient, comfortable, well lighted work area should be available to the
operator. The work area should specifically be free of all flammables with
both a fire extinguisher and bucket of sand available.
To properly prepare for welding, it is necessary to:
1.
Prepare an organized, well lighted work area
2.
Provide protection for the eyes and skin of the operator and
bystanders.
3.
Set up the work piece and make the ground clamp connection.
4.
Select the electrode.
5.
Turn the power switch on.
4.2
SETTING UP THE WORK PIECE
Welding Positions
arc welding can be performed in any of the four basic positions: Flat,
Horizontal, Vertical and Overhead. Flat welding is generally easier,
faster, and allows for better penetration. Overhead welding is the most
difficult. The (rod) selections will be affected by the positions. Vertical and
overhead welding are usually only attempted when using a welder with dc
welding capabilities.
If possible, the work piece should be positioned so that the bead will run
on a flat surface.
Preparing The Joint
For effective welding, the surfaces to be joined must be free of dirt, rust,
scale, oil or paint. Welding on metals not properly cleaned will cause a
brittle and porous weld.
If the base metal pieces to be joined are thick or heavy, it may be
necessary to bevel the edges, with a metal grinder, at the point of contact,
as shown below. The angle of the bevel should be approximately 60
degrees. If utilizing a grinder, be sure to follow all manufacturer warnings
and procedures.
See the chart below for detailed instructions for preparing the weld joint.
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