Failure Analysis

• Why ?

As the standards of our industry rise due to increasing globalization and competition, there is an ever growing need for consistency and reliability. Breakdown of any unit, system or equipment is an avoidable and costly occurrence and must be prevented or minimized. Analysis of such failures becomes a resourceful and affordable tool in addressing such unwanted occurrences.

To establish whether the cause of component failure lay on:

a) Service conditions
b) Design considerations
c) Material and its specification
d) Improper processing and assembly procedures or
e) Combinations of these.

01-RootCause-root cause analysis cycle-problem solving steps-avoidance of recurring problems

Only the real “Root cause” can ensure the effectiveness of corrective and preventive actions and avoid recurrence of failure..

01-CauseEffect-analysis-bottom up predictive-ishikawa - fishbone diagram-prediction analysis

• Stages Of Failure Analysis

1. Understanding and assimilation of background data and selection of samples.
2. Examination and documentation of the failed part by the following

1. Visual examination of parts, location (if necessary) and relevant photographs as well.

01-visual examination-metallographic examination-appearance of the parts-calibrated metallurgical microscope equipment-image analysis-microstructure

2. Non destructive testing by means of Radiography, Dye penetrant, Magnetic particle testing etc.

01-NDT-non destructive testing-cold process-radiography-die penetrant techniques-magnetic particle testing

3. Mechanical Testing for various physical properties.

3. Vital specimens are selected, classified, and subjected to:

Macroscopic examination and analysis. This involves examining the fracture surfaces, secondary cracks, deposits and other such elements
Microscopic examination and analysis of fracture surface (by Scanning Electron Microscopy, if required).

$01-scanning-electron-microscopy-vital specimens-fracture surfaces-secondary cracks-microscopic examination$

4. Chemical analysis of material for conformation to specifications.

5. Chemical analysis of corrosion products, deposits, contaminants etc.

01-corrodedmetal-corrosion in metals-material technology-material science and metallurgy-iron oxidization-low affinity with oxigen-electrochemical corrosion-oxidation

6. The actual state of the failed part and the failure mode are established.

7. Fracture mechanics study if found necessary.

01-connection_failure_analysis-comprehensive failure analysis-analysis and testing-investigation of failure-design life check-failure mechanisms-identification of causes of failure

8. A simulation of the identical working environment to determine if any external factors have contributed to the failure

9. Conclusions are determined after compiling all evidences and analysis and then the report is generated.
10. Follow-up recommendations are also provided.

Comments

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