MATERIAL DEFECT

MATERIAL DEFECT

We  will come across many material defects in a project. Some defects are identified visually, some are identified at the time of radiography of weld joints and some are identified at the time of hydrotest.

Attached here with a video of crack in a reducer which is identified at the time of hydrotest.
Crack in a TEE identified at the time of Hydrotest

Crack in a reducer identified at the time of Hydrotest


The photos below shows the crack identified in a reducer. The defect was seen in the radiography of the weld joint, when grinded and tested with liquid penetrant method the defect was clearly visible.






The actions that are to be taken after identification of such a defect is the most important thing .

1. The batch number/heat number of the defect material is to be taken.


2. Identify the manufacturer and purchase order details.


3. Identify the quantity of the materials that are supplied by the manufacturer with the same heat number.


4. Identify how much quantity of the same heat number materials are issued and identify which contractor/which project/which area it is issued. 


5. Identify against which isometric line numbers/isometric drawing numbers it is issued.


6. Physically check some isometric line numbers, for that component and check the  heat number of the component.


7. Do radiogrqphy testing/ ultrasonic testing, what ever, to check whether the identified defect is in that component.


8. If the used quantity is in large numbers, testing of  a 10% sample will serve the purpose.


9. If no further defects are detected, the issue can be closed by replacing the defect material.


10. If further defects are detected, the entire lot is to be identified and tested.


11. The issues are to be informed to the vendor and the tests are to be done in his presence and/or cost according to contract condition.


12. The vendor is to be evaluated, based on the defects found and black listing/degrading actions to be taken.


13. The entire process is to be recorded for future reference.


14. For preventing the future use of the defect material the fool proof method is to damage it by gas cutting or by drilling holes in it. 


Below image shows an elbow and Tee cut by gas cutting process to prevent future use.



Comments