ROOT CAUSE FAILURE ANALYSIS REPORT
LO GEAR PUMP DG#4 PLTD TENAU (CLAIM)
A) Root Cause Analysis Report
Individual Completing Report
: M. Pandu Setiawan
Date of Report
: 25 Agustus 2023
B) Detail Of The Failure
Equipment
: LO Gear Pump DG #4 (Claim)
Customer
: PLN IP PLTD Tenau
Date of Failure
: 11 August 2023
Work Order
: 23F007
C) Problem Statement
The following problem statement is related to a fault event on the LO gear pump DG#4:
Indications of failure in the Lo gear pump are caused by insufficient oil pressure, so the bearing is not well lubricated.
As a result, it causes overheating of the bearings, characterized by the appearance of thick smoke. This is the cause of
the LO gear pump jammed.
D) Root Cause Identification
1. Team Involved in RCFA
-
Quality Control
-
Engineer
-
Production
2. Tools Used for RCFA
A Fishbone Diagram was completed and embedded in this document
3. Identification Root Cause
On August 11, 2023 :
09.45 : Start Running (Running Normal)
09.50 : Engine Stop (Normal Big End Axial Check/No findings)
10.25 : Start Running (Normal Operation) Continued checking with Idle Speed
10.35 : There is an indication of abnormal noise from the LO Gear Pump accompanied by smoke on the Oil Mist
Separator, the engine inlet pressure tends to decrease
10.35 : Engine Trip with indication of LO Low engine inlet pressure (Along with Emergency Shutdown / Push Botton
UNIC & CFC)
Findings :
- There is thick smoke from the sumptank when the cover is opened
- There is a burnt indication on the LO Gear Pump on the DE side (Gear Shaft)
Note : The results of the Axial Big End check are still normal after the trip
E) Proposed Plan of Action
Area of Concern (Root Cause)
Oil groove design on sleeve bearing
Target Clearance
Oil groove design on bush bearing
Prevention
- The design of the oil groove given to us must be correct
- Oil groove width 6mm
- Oil groove depth 3mm
Clearance refers to the manual book
The design of the oil groove back to original
F) Conclusion
1. Before making spare parts, witnesses have been carried out by the user. The design and dimensions have been
mutually agreed upon.
2. Overheat in the bush bearing caused by incorrect oil groove design in the sleeve bearing. Marked by a burned area
on the cover.
3. Oil groove modification in the bush bearing is not a cause of failure, but is caused by lack of oil in the bush bearing
that causes overheat and cracked.
4. Bearing clearance refers to the manual book.
5. The shaft is jammed due to a cracked bearing.
6. Before the LO Gear Pump DG #4 leave the workshop, a final check has been carried out with good results.
Prepared By :
Checked By :
Approved By :
Approved By :
PT Sinar Sakti Matra
Nusantara
PT Sinar Sakti Matra
Nusantara
PT Sinar Sakti Matra
Nusantara
PLN IP PLTD Tenau
M. Pandu Setiawan
Rachmat
Busro Rasyid
Date : 25 Agustus 2023
Date : 25 Agustus 2023
Date :
Date :
G) Attachment
Fig. 1 Scratch and burnt on bush bearings
Fig. 2 Gear shaft scratches and jammed when removed
from bush bearings
Fig. 3 Housing bush bearing crack
Fig. 4 Drive gear wear and burnt