PLANT AVAILABILITY DEPARTMENT

ASSET INTEGRITY SECTION

PRELIMINARY INSPECTION REPORT OF BOILER-A

EQUIPMENT IDENTIFICATION

Equipment/ Item: 120-0B0400 A Report No: QOPS/AI/GI/1774

Report Prepared By: Arumugam Ravi Insp. Date: 08/07/2012

Scope: Inspection and identify the vibration issue in the burner

BACKGROUND

Serious vibration was reported in HHP Boiler-A (1210B0400A) by operation

Hot spot was noted on the back side of Burner A3 & A4 (Top)

Subsequent inspection by temperature verification revealed the skin temperature was 150-170Deg.C

Production reduced the boiler load to below 50%, re-verified the temperature on hot spot area and found remain same.

Finally the production decided to shutdown the boiler-A

INSPECTION FINDINGS

Intrusive Inspection was carried out in Boiler-A at fire box (Radiant section) super heater coil, burners and observation and findings as follow: As Open Inspection:

As open inspection revealed water leak on east side water wall tube

Refractory on burner, man way was found in good condition

In super heater section, Most of the anti-vibration devises of Final super heater found slipped down from its original position due to boiler vibration and abrasion damage to adjacent water wall tube and deep groove noted approx. 1.00mm.

Severe sand deposit was noted on flue gas path (Water wall, primary & secondary super heater coil)

Detailed Inspection

Tube leak was identified and visual inspection reveled that the crack initiated from support weld on the tube and propagated through wall thickness in east side

West side similar support was inspected by DP Testing and found crack minor surface crack on the support weld. However the crack was propagating towards support plate

Boroscopy confirmed the fuel gas tubes were partially / fully chocked

Deposits were observed in fuel gas and flue gas chamber

Control valve FV 1310 was removed for inspection and found stones/debris at upstream of the valve.

IWL/repair procedure issued to FM

After window cutting of cracked support weld, internal surface of water wall tube found no corrosion or erosion and extremely in good condition.

PLANT AVAILABILITY DEPARTMENT

ASSET INTEGRITY SECTION

PRELIMINARY INSPECTION REPORT OF BOILER-A

Recommendations 1. Follow-up with Macchi for burner vibration, strainer requirement on fuel gas inlet line

(Action By AI) 2. Carry out detailed integrity study of all boilers through third party consultant (Action By

AI/Engineering) 3. Repair/ restore the leak tube as per issued IWL (Action By FM) 4. Cleaning of burner FG/Flue gas tubes as per IWL (Action By FM)

PREPARED BY Arumugam Ravi Inspection and NDT Supervisor

18 Jul 2012

APPROVED BY Rajan Konedana Head Of Asset Integrity& Inspection

18 Jul 2012

NAME DESIGNATION SIGNATURE DATE

ATTACHMENT - PHOTO

Leak at Support weld

Burner Refractory in good condition Support crack at west side

Leak at Support weld after DP Test

PLANT AVAILABILITY DEPARTMENT

ASSET INTEGRITY SECTION

PRELIMINARY INSPECTION REPORT OF BOILER-A

Anti vibration plate damages adjacent tube

Boroscope images of burner Tube chock

Boroscope images of burner Tube chock

Slipped down anti vibration supports Sand accumulation/deposit

Window cutting of defective support weld

PLANT AVAILABILITY DEPARTMENT

ASSET INTEGRITY SECTION

PRELIMINARY INSPECTION REPORT OF BOILER-A

Support weld crack