erhari30
Mechanical
- Jul 19, 2010
- 2
Branched Crack was identified for about 80mm length with zig-zag pattern on Dissimilar welded tubes
between S213TP347H to SA213T91; The crack had branching exactly 3 lines seperated by 120 deg at an
isolated distance of 25 mm; All were joined by a continuous line (which revealed in LPI examination)
One side of crack was originated from HAZ on 347H side and crack runs on 347H side for about 80mm length.
JOB: Superheater coil
SERVICE : NOT PUT INTO SERVICE/UNDER MANUFACTURE STAGE
PWHT: Local Stress Relieving by REsistance method done
Hydro Test at 450 KSC for 5 minutes completed
CRACK WAS OBSERVED DURING VISUAL EXAMINATION
Please throw more light on the root cause for such crack on 347H material.
between S213TP347H to SA213T91; The crack had branching exactly 3 lines seperated by 120 deg at an
isolated distance of 25 mm; All were joined by a continuous line (which revealed in LPI examination)
One side of crack was originated from HAZ on 347H side and crack runs on 347H side for about 80mm length.
JOB: Superheater coil
SERVICE : NOT PUT INTO SERVICE/UNDER MANUFACTURE STAGE
PWHT: Local Stress Relieving by REsistance method done
Hydro Test at 450 KSC for 5 minutes completed
CRACK WAS OBSERVED DURING VISUAL EXAMINATION
Please throw more light on the root cause for such crack on 347H material.
