A straight-looking assembly is not a complete stress record.
Name the two outcomes
TWI explains that restraint can reduce movement while retaining higher residual stress. Distortion and residual stress therefore belong to different observation fields. Primary reference: TWI technical explanation.
One concerns changed shape; the other concerns stress remaining after the thermal event and external process loads are removed. An apparently small dimensional change cannot be substituted for an assessment of the retained stress condition.
Read a hypothetical comparison
Imagine fictional assembly A has a documented small shape deviation after cooling, but no residual-stress assessment. Assembly B has a greater observed shape change. Ranking their retained stress solely from those deviations would add unsupported information.
The geometry records do not contain the needed stress measurements or analysis. Nor does visible distortion alone establish one particular stress distribution. These descriptions identify an evidence boundary rather than outcomes from a real restraint trial.
Preserve both review questions
Prepare separate rows for shape before/after joining, restraint history and any residual-stress assessment. Keep the relevant joint region, coordinate basis and method with each observation. A released geometry measurement and a stress result may address different requirements.
Ask which outcome the application needs to control and what supports that conclusion. The worksheet does not recommend clamping, weld sequence or stress-relief treatment. It prevents a favorable appearance or one dimensional result from being promoted into an unsupported claim about the assembly’s complete post-weld state.
Customer Questions
Does small distortion prove low residual stress?
The geometry result does not supply that stress assessment.
Can restraint affect both questions differently?
The cited discussion separates reduced movement from retained stress.
What should the review record keep separately?
Shape observations and the corresponding stress evidence.
Primary References
These references support the technical principles discussed in this guide. The worked examples and review questions are educational.
Discuss Your Machine Requirement
Share your product, container, required output and the evidence needed for your technical review.
Request a Technical Review