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Boiler Feed Water Pump Inspection at Jubail
TM.P. Workshop
March 22 & 23, 2015
Done by:
Name Badge no. Faris Al-Abdulaali 100756
Abdullah Al-Esmail 93362
2
Table of Contents Brief Description of The Problem: ................................................................................................... 3
Visit Report: ..................................................................................................................................... 3
Disassembly of the pump parts: .................................................................................................. 3
Damaged Parts: ........................................................................................................................... 5
- 1st stage impeller damaged wear ring: ............................................................................ 6
- Suction casing damaged wear ring: ................................................................................. 6
Assembly of BFP: ......................................................................................................................... 8
General Observations: .................................................................................................................. 12
1- No procedure papers available to implement it during installation. ............................ 12
2- Deep cutting in the shaft ............................................................................................... 12
3- Poor preservation of tools ............................................................................................. 13
4- Improper heating method ............................................................................................. 13
5- Air cooling after heating ................................................................................................ 14
6- Casing stages installation .............................................................................................. 15
7- Cleaning of parts ............................................................................................................ 16
8- Arrangement of visit ...................................................................................................... 17
9- Workshop Facility .......................................................................................................... 17
Conclusion: .................................................................................................................................... 17
3
Brief Description of The Problem:
During first start-up/commissioning of BFP of pump no. 2 at HRSG A112, the pump
jammed and resist to operate. BEMCO called TMP representative and explained the
issue. The TMP representative decided to take the pump to Al-Jubail TM.P. Workshop to
full dismantle the pump and diagnose the problem.
Visit Report:
A visit to the workshop has been conducted by Project team with a joined team from
Generation to inspect the issue and see the root cause of this failure. The same
representative from TM.P who was at PP10 site was also present for disassembly and
assembly of the pump at Al-Jubail Workshop.
Below are photos with remarks of the visit.
Disassembly of the pump parts:
Dismantlement of the pump parts has been done prior the arrival of SEC team.
Figure 1: Pump diffusers and impellers
4
Figure 2: Pump shaft
Figure 3: Full disassembled parts
5
Damaged Parts:
Two (2) wear rings have been effected and strong rubbing marks observed on both sides
diameters (ID & OD) due to the great jamming occurred between the Suction casing
(stationary) wear ring and 1st stage impeller (rotating) wear ring. See below photos.
Figure 4: Stationary and rotatory damaged wear rings
Figure 5: Stationary and rotatory damaged wear rings
6
- 1st stage impeller damaged wear ring:
Figure 6: 1st
stage impeller wear ring
Figure 7: 1st
stage impeller wear ring
- Suction casing damaged wear ring:
Figure 8: Suction casing wear ring
7
Figure 9: Suction casing wear ring
The replacement of these damage rings has already been done by the vendor and TIG welded to
the casing and the impeller.
Figure 10: Replaced (new) impeller wear ring
8
Figure 11: Replaced (new) stationary wear ring
Assembly of BFP:
After inspection of the damaged parts, TM.P started the assembly of the pump. The pump
assembly activity requires a 3 days minimum to finish. See below photos which illustrate the
assembly process.
Figure 12: Pump shaft marking of Keys for impellers
9
Figure 13: Heating of impellers for thermal elongation
Figure 14: Impeller insertion done and waited to be cooled
10
Figure 15: Starting the vertical assembly of 1st
stage impeller & following inter-stages impellers and diffusers casing
Figure 16: Greasing of the diffuser and installation in shaft
11
Figure 17: Inter-stages installation
Approximately half of the inter-stages have been observed and the complete installation
observation could not done due to time concern of visit.
12
General Observations:
1- No procedure papers available to implement it during installation.
2- Deep cutting in the shaft
Figure 18: Shaft deep cutting
Wrong machining in the shaft noted and it was left as it is. Vendor commented that it
will not affect the assembly process or performance of the pump.
Clarification is required whether to accept this or not.
13
3- Poor preservation of tools
The greasing and oil reservoir are improper.
Figure 19: Improper greasing and oil
4- Improper heating method
It was observed that flame heating by torch was the method used to heat the impellers for
linear expansion for shrink fitting onto the shaft which leads to non-homogeneous
distribution of heat.
Figure 20: Improper heating method
14
Heating furnace is required to achieve uniform heating.
5- Air cooling after heating
After a while when the impeller has been positioned in the shaft, cooling by air has been done
which may affect the hardness of the material and cause non-uniformity cooling.
Figure 21: Cooling the impeller by air
15
6- Casing stages installation
It was observed that no. 9 casing has been installed instead of no. 6. Vendor commented that it
will not make an issue since no. 6 & no. 9 stages are identical.
A clarification is required.
Figure 22: Diffusers Casing
16
7- Cleaning of parts
Poor tools of cleaning by air and cotton waste.
Figure 23: Dirt inside the pump suction nozzle
Figure 24: Surface not clean inside the impeller
17
8- Arrangement of visit
The inspection was carried out without the presence of BEMCO. While TM.P claims that the
issue root cause was during the installation work done by BEMCO. This visit shall be joint visit by
BEMCO.
9- Workshop Facility
The workshop of TM.P at Al-Jubail does not have the proper equipment in order to test the
pump after installation. The machines available there are only sufficient for machining for small
prepares and maintenance.
Conclusion:
Jamming of the BFP A112 took place at Site while commissioning stage. The wear rings
damage/rubbing of the Suction & 1st stage have been occurred due to foreign materials went
inside the suction nozzle of the pump during the installation or hot working or re-instatement of
the pump at Site by BEMCO as per TM.P claim.
TM.P has already replaced the damaged wear rings and install them.
A better arrangement of the visit with the presence of BEMCO was expected.
Balancing of the Shaft assembly needs to be checked static or dynamic.
Hydrostatic test of the Pump shall be done.
Furthermore, high standards, quality and safety was expected than the reality.