Boiler Feed Water Pump Inspection at Jubail TM.P. Workshop.pdf

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.