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SET-UP AND SAFE OPERATING PROCEDURES
0056-0114
TIPS TO IMPROVE WELD QUALITY
Problem Features Corrective Action
2. Improper welding procedure and flame
adjustment.
2. Select proper size welding rods to obtain a
balance in the heat requirements for melting
welding rod, breaking down side-walls and
maintaining the puddle of molten metal
at the desired size. Use small diameter
welding rods in a narrow welding groove.
3. Insufficient puddling time to allow
entrapped gas, oxides and slag inclusions
to escape to the surface.
3. Use sufficient heat input to obtain proper
penetration for the plate thickness being
welded.
4. Poor base metal. 4. Welding speed should be slow enough
to allow welding heat to penetrate to the
bottom of the joint.
Brittle Welds
1. Unsatisfactory welding rod producing air-
hardening weld metal.
1. Avoid welding rods producing air-
hardening weld metal where ductility is
desired. High tensile low alloy steel rods
are air-hardening and require proper base
metal preheating, post-heating or both, to
avoid cracking due to brittleness.
2. Excessive heat input with over-sized
welding tip, causing coarse-grained and
burned metal.
2. Do not use excessive heat input, as this
may cause coarse grain structure and oxide
inclusions in the weld metal deposits.
3. High carbon or alloy base metal which has
not been taken into consideration.
3. A single pass weld may be more brittle
than a multi-layer weld, because it has not
been refined by successive layers of weld
metal. Welds may absorb alloy elements
from the parent metal and become hard.
Do not weld a steel unless the analysis and
characteristics are known.
4. Improper flame adjustment and welding
procedure.
4. Adjust the flame so that molten metal does
not boil, foam or spark.
Poor Fusion
1. Improper size of welding rod. 1. When welding in narrow vees, use a welding
rod small enough to reach the bottom.
2. Improper size of tip and heat input. 2. Use sufficient heat to melt the welding rod
and to break down the side walls of the
plate edges.
Welding Procedures
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