6-40
SET-UP AND SAFE OPERATING PROCEDURES
0056-0114
TIPS TO IMPROVE WELD QUALITY
Problem Features Corrective Action
Warping (Thin Plates)
1. Shrinkage of deposited weld metal. 1. Design the structure and develop a
welding procedure to eliminate rigid joints.
2. Excessive local heating at the joint. 2. Do not use too small a weld between
heavy plates. Increase the size of welds by
adding more filler metal.
3. Incorrect preparation of the joint. 3. Do not make welds in string beads. Make
welds full-size in short sections 7.5” to
10” in length. Welding sequence should
be such as to leave ends free to move as
long as possible. Preheating the parts to
be welded sometimes helps to reduce high
contraction stresses caused by localized
high temperatures.
4. Improper welding procedure. 4. Make sure welds are sound and the fusion
is good
5. Improper clamping of parts 5. Prepare the joints with a uniform and proper
gap. In some cases a gap is essential. In
other cases a pressed fit may be required.
Poor Weld Appearance
1. Poor welding technique: Improper flame
adjustment or welding rod manipulation.
1. Use the proper welding technique for the
welding rod used. Do not use excessive
heat. Use a uniform flame rotation and
welding speed at all times.
2. Inherent characteristics of the welding rod
used.
2. Use a welding rod designed for the type of
weld.
3. Improper joint preparation. 3. Prepare all joints properly.
Undercut
1. Excessive flame rotation of the torch,
improper tip size and insufficient welding
rod added to molten puddle.
1. Modify welding procedure to balance flame
rotation of the bead and rate of welding
rod deposition, using proper tip size.
2. Improper manipulation of the welding rod. 2. Avoid excessive and non-uniform flame
rotations. A uniform flame rotation with
unvarying heat input will aid greatly in
preventing undercut in butt welds.
Welding Procedures
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