Definition
The material to be welded has a different base chemistry, processing,
or coating than that specified for the part.
Description
The metal type and coating have a large affect on weldability. Any of
the following conditions may require weld schedule changes:
- Substitution of any material by another that has different base
metal characteristics (such as base metal chemistry, hardness, or
processing).
- Substitution of a coated steel (electrogalvanized, hot dip galvanized,
or galvannealed) for another steel with the same base metal, but a
different coating material or thickness.
- Substitution of a bare steel (no coating) for a coated steel, or
vice versa.
- Substitution of a plated steel part for a coated or unplated part,
or vice versa.
- The above considerations should also be applied to aluminum and
its coatings (conversion coatings, etc.)
Detection
Detectable evidence may include:
Significance
Quality, Workplace Issues, Cost, Downtime, Maintenance, Throughput (cycle
time; PPH), are all potentially affected by this condition. Special
considerations are noted below:
Cost: Substitution of an incorrect metal and/or
coating can affect all of the welds made on the part, so weld repair
may be extensive, and, in the worst case, require scrapping of the parts.
Subordinate Causes
- Material substitution not reported throughout process/plant
- Substitution necessary because of a shortage of the specified material
- Parts erroneously made of the incorrect material
- Parts have been plated because of corrosion concerns
- Parts should have been plated, but this step was erroneously omitted
WeldHelp: To Issue/Cause
Matrix
| To Issue Photo Gallery | Home
|
