Improving your SMAW welding technique
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Transcript of Improving your SMAW welding technique
Prepared by: Lawrence Lerias
• SMAW—shielded metal arc welding is one
of the more difficult processes to learn.
• Metal preparation is a must
•
• Use a wire brush or grinder to remove dirt,
grime or rust from the area to be welded.
• Unclean conditions can lead to cracking,
porosity, lack of fusion or inclusions.
• Make sure you have a clean spot for the
ground clamp. A good, solid electrical
connection is important to maintain arc
quality.
• Position yourself so you have good view of the
weld puddle. Keep your head off to the side and
out of the smoke so you can be sure you’re
welding in the joint.
• Make sure your stance will allow you to
comfortably support and manipulate the
electrode.
•Current setting
•Length of arc
•Angle of electrode
•Manipulation of the electrode
•Speed of travel
• Correct current/amperage setting depends on the
diameter and type of electrode to be used. Electrodes
operating ranges are usually indicated on the box.
• General rule of thumb is 1 amp for each .001 inch of
electrode diameter.
Here a 1/8” (.125 inch)
electrode is used,
so the operator starts
at 125 amps
Current setting is too low. The arc will stutter and the
electrode will be sticky. Low penetration on base metal.
Current setting is too high. The puddle will be
excessively fluid and hard to control. This can lead to
excess spatter and higher potential for undercut.
The electrode glows because of too high amperage
setting.
Arc length should not exceed the diameter of themetal portion (core) of the electrode, e.g. an 1/8-in.6010 electrode is held about 1/8 in. off the basematerial.
Correct arc
length varies
with each
electrode and
application.
• Holding the electrode too closely to the joint decreases
welding voltage, which creates an erratic arc that may
extinguish itself or cause the electrode to freeze faster
and produces a weld bead with a high crown.
• Too long of an arc length will create excess
spatter in the weld joint. There is also a high
potential for undercut.
Stick welding in the
flat, horizontal and
overhead position
uses a “drag” or
“backhand” welding
technique.
Hold the electrode perpendicular to the joint, and then tilt the
direction of travel approximately 5 to 15 degrees. For
welding vertical up, use a “push” or “forehand” technique
and tilt the top of the electrode 0 to 15 degrees away from
the direction of travel
• Each welder manipulates the electrode a little differentlythan the next.
• Develop your own style by observing others, practicingand noting which techniques produce the best results.
• To create a wider bead on thicker material, manipulatethe electrode from side to side motion to cover a widerarea.
• Note that on material 1/4 in. and thinner, weaving theelectrode is typically not necessary because the bead willbe wider than necessary. In many instances a straightbead is all that’s needed.
Here the welder uses a semi-circular
motion to create a wider bead with a
“stacked dimes” appearance.
• Your travel speed
should allow you to
keep the arc in the
leading one-third of
the weld pool.
First, establish a weld puddle of the desired
diameter, and then move at a speed that keeps you
in the leading one-third of the puddle.
• Traveling too
slowly
produces a
wide, convex
bead
• Slow travel speed will create too much weld
deposit.
• This can result in insufficient penetration.
• It can also focus the heat into the puddle and not
into the base material.
• Excessively fast
travel speeds
creates a
concave or
recessed weld.
Traveling too fast will create a thinner/undersized
bead that will have more of a “V”- shaped ripple
effect in the puddle rather than a nice “U” shaped, or
“stacked dimes” effect.
• 1. Practice your welding technique.
• 2. Practice CLAMS.
• 3. Practice even more.
The key to acquiring proficiency in any task is
repetition – Leonard Hofstadter (TBBTS8E8)
• End of slide
• Thanks you
• Prepared by Lawrence Lerias
• Photos and contents courtesy of www.milerwelds.com